<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Filtration vs Crystallisation</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    }
    body {
      width: 100%;
      background: transparent;
      color: #1e2945;
      padding: 10px 12px;
      display: flex;
      justify-content: center;
      align-items: flex-start;
      overflow-x: hidden;
    }
    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
      width: 100%;
      max-width: 680px;
      align-items: stretch;
    }
    @media (max-width: 540px) {
      .grid {
        grid-template-columns: 1fr;
        gap: 16px;
      }
    }
    .panel {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 6px 4px;
    }
    .panel-title {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
      margin-bottom: 6px;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      text-align: center;
    }
    .svg-container {
      width: 100%;
      max-width: 260px;
      position: relative;
      display: flex;
      justify-content: center;
      align-items: center;
    }
    svg {
      width: 100%;
      height: auto;
      display: block;
    }
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      margin-top: 8px;
      min-height: 32px;
    }
    .btn {
      background: #ffffff;
      border: 1.5px solid #64748b;
      color: #1e2945;
      padding: 5px 12px;
      font-size: 12px;
      font-weight: 700;
      border-radius: 6px;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: background 0.6s ease, color 0.6s ease, border-color 0.6s ease;
    }
    .btn:hover {
      background: #f1f5f9;
      border-color: #1e2945;
    }
    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }
    .stage-pill {
      font-size: 12px;
      font-weight: 700;
      color: #1e2945;
      background: #e2e8f0;
      padding: 5px 12px;
      border-radius: 6px;
      margin-top: 8px;
      display: inline-flex;
      align-items: center;
      min-height: 32px;
      text-align: center;
    }
    .cryst-group {
      transition: opacity 0.6s ease-in-out;
      opacity: 1;
    }
    .cryst-group.hidden {
      opacity: 0;
      pointer-events: none;
    }
    @keyframes dripMotion {
      0% {
        transform: translateY(0);
        opacity: 0.95;
      }
      65% {
        transform: translateY(24px);
        opacity: 0.95;
      }
      100% {
        transform: translateY(30px);
        opacity: 0;
      }
    }
    .drip-animated {
      animation: dripMotion 2.2s infinite ease-in;
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="panel">
      <div class="panel-title">1. Filtration</div>
      <div class="svg-container">
        <svg viewBox="0 0 240 210" aria-label="Filtration apparatus diagram">
          
          <g transform="translate(42, 24) rotate(-35)">
            <rect x="-15" y="-28" width="30" height="38" rx="3" fill="none" stroke="#475569" stroke-width="2"/>
            <path d="M-15 -4 L 15 -4 L 15 8 L -15 8 Z" fill="#38bdf8" opacity="0.7"/>
            
            <circle cx="-5" cy="1" r="3.5" fill="#854d0e"/>
            <circle cx="6" cy="3" r="3.5" fill="#854d0e"/>
          </g>
          
          
          <path d="M 64 34 Q 82 48 94 62" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round"/>

          
          <polygon points="68,62 148,62 114,110 114,140 104,140 104,110" fill="#f8fafc" stroke="#475569" stroke-width="2"/>
          <polygon points="74,65 142,65 109,107" fill="#ffffff" stroke="#94a3b8" stroke-width="1.5"/>

          
          <circle cx="96" cy="82" r="4.5" fill="#854d0e"/>
          <circle cx="110" cy="87" r="5" fill="#854d0e"/>
          <circle cx="120" cy="79" r="4.5" fill="#854d0e"/>
          <text x="162" y="82" font-size="11" font-weight="700" fill="#1e2945">Residue</text>
          <line x1="158" y1="79" x2="126" y2="82" stroke="#1e2945" stroke-width="1.5" stroke-dasharray="2,2"/>

          
          <g class="drip-animated">
            <ellipse cx="109" cy="144" rx="2.5" ry="4" fill="#0284c7"/>
          </g>

          
          <polygon points="97,135 121,135 121,150 160,198 58,198 97,150" fill="none" stroke="#475569" stroke-width="2"/>
          
          <polygon points="66,192 152,192 140,170 78,170" fill="#38bdf8" opacity="0.75"/>
          
          
          <circle cx="88" cy="182" r="2.2" fill="#b45309"/>
          <circle cx="108" cy="186" r="2.2" fill="#b45309"/>
          <circle cx="128" cy="180" r="2.2" fill="#b45309"/>
          <circle cx="98" cy="174" r="2.2" fill="#b45309"/>
          <circle cx="118" cy="176" r="2.2" fill="#b45309"/>

          <text x="168" y="182" font-size="11" font-weight="700" fill="#1e2945">Filtrate</text>
          <line x1="164" y1="179" x2="140" y2="179" stroke="#1e2945" stroke-width="1.5" stroke-dasharray="2,2"/>
        </svg>
      </div>
      <div class="stage-pill">Separates Insoluble Solids</div>
    </div>

    
    <div class="panel">
      <div class="panel-title">2. Crystallisation</div>
      <div class="svg-container">
        <svg viewBox="0 0 240 210" id="crystSvg" aria-label="Crystallisation apparatus diagram">
          
          <g id="crystHeat" class="cryst-group">
            <text x="120" y="20" text-anchor="middle" font-size="12" font-weight="700" fill="#1e2945">Evaporate Solvent (Heat)</text>
            
            
            <path d="M100 58 Q 95 44 100 35" fill="none" stroke="#94a3b8" stroke-width="2" stroke-linecap="round"/>
            <path d="M120 53 Q 125 39 120 30" fill="none" stroke="#94a3b8" stroke-width="2" stroke-linecap="round"/>
            <path d="M140 58 Q 135 44 140 35" fill="none" stroke="#94a3b8" stroke-width="2" stroke-linecap="round"/>

            
            <path d="M62 78 Q 120 126 178 78 Z" fill="#ffffff" stroke="#475569" stroke-width="2"/>
            <path d="M72 83 Q 120 120 168 83 Z" fill="#38bdf8" opacity="0.8"/>

            
            <circle cx="98" cy="94" r="2.2" fill="#b45309"/>
            <circle cx="120" cy="98" r="2.2" fill="#b45309"/>
            <circle cx="142" cy="94" r="2.2" fill="#b45309"/>

            
            <rect x="75" y="98" width="90" height="52" rx="3" fill="none" stroke="#475569" stroke-width="1.5"/>
            <rect x="76" y="116" width="88" height="33" fill="#bae6fd" opacity="0.8"/>

            
            <line x1="60" y1="150" x2="180" y2="150" stroke="#1e2945" stroke-width="2.5"/>
            <line x1="70" y1="150" x2="56" y2="195" stroke="#475569" stroke-width="2.5"/>
            <line x1="170" y1="150" x2="184" y2="195" stroke="#475569" stroke-width="2.5"/>

            
            <path d="M120 195 Q 108 175 120 160 Q 132 175 120 195 Z" fill="#f59e0b"/>
            <path d="M120 195 Q 114 180 120 168 Q 126 180 120 195 Z" fill="#dc2626"/>
          </g>

          
          <g id="crystCool" class="cryst-group hidden">
            <text x="120" y="24" text-anchor="middle" font-size="12" font-weight="700" fill="#0284c7">Pure Crystals Form</text>
            <text x="120" y="42" text-anchor="middle" font-size="11" font-weight="600" fill="#475569">on slow cooling</text>

            
            <path d="M52 108 Q 120 172 188 108 Z" fill="#ffffff" stroke="#475569" stroke-width="2.5"/>
            
            <path d="M68 116 Q 120 164 172 116 Z" fill="#bae6fd" opacity="0.75"/>

            
            <polygon points="105,142 115,132 125,142 115,152" fill="#0284c7" stroke="#0369a1" stroke-width="1.5"/>
            <polygon points="85,137 95,129 103,138 93,146" fill="#0284c7" stroke="#0369a1" stroke-width="1.5"/>
            <polygon points="130,138 142,130 150,139 138,147" fill="#0284c7" stroke="#0369a1" stroke-width="1.5"/>
            <polygon points="112,128 122,118 130,127 120,137" fill="#0369a1" stroke="#0c4a6e" stroke-width="1.5"/>

            
            <circle cx="80" cy="122" r="2.2" fill="#b45309"/>
            <circle cx="160" cy="122" r="2.2" fill="#b45309"/>
            <circle cx="145" cy="118" r="2.2" fill="#b45309"/>

            
            <text x="120" y="186" text-anchor="middle" font-size="11" font-weight="700" fill="#1e2945">Pure Crystals + Mother Liquor</text>
          </g>
        </svg>
      </div>
      <div class="controls">
        <button class="btn active" id="btnHeat" type="button">1. Heat</button>
        <button class="btn" id="btnCool" type="button">2. Cool</button>
      </div>
    </div>
  </div>

  <script>
    const btnHeat = document.getElementById('btnHeat');
    const btnCool = document.getElementById('btnCool');
    const crystHeat = document.getElementById('crystHeat');
    const crystCool = document.getElementById('crystCool');

    function showHeat() {
      btnHeat.classList.add('active');
      btnCool.classList.remove('active');
      crystHeat.classList.remove('hidden');
      crystCool.classList.add('hidden');
    }

    function showCool() {
      btnCool.classList.add('active');
      btnHeat.classList.remove('active');
      crystHeat.classList.add('hidden');
      crystCool.classList.remove('hidden');
    }

    btnHeat.addEventListener('click', showHeat);
    btnCool.addEventListener('click', showCool);
  </script>
</body>
</html>

Analysing Physical Properties to Select Separation Methods

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: #ffffff;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-start;
      padding: 8px 4px;
      width: 100%;
    }
    .header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 760px;
      padding: 0 10px 6px;
    }
    .title {
      font-size: 15px;
      font-weight: 700;
      color: #1e2945;
    }
    .btn-group {
      display: flex;
      gap: 6px;
    }
    .btn {
      font-size: 12px;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 6px;
      border: 1px solid #cbd5e1;
      background: #f8fafc;
      color: #1e2945;
      cursor: pointer;
      transition: all 0.2s ease;
    }
    .btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
    }
    .svg-container {
      width: 100%;
      max-width: 760px;
      aspect-ratio: 4/3;
      max-height: 480px;
    }
    svg {
      width: 100%;
      height: 100%;
      display: block;
    }
    .label {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      font-size: 12px;
      fill: #1e2945;
      font-weight: 600;
    }
    .sublabel {
      font-size: 10.5px;
      fill: #64748b;
      font-weight: 500;
    }
    .badge-text {
      font-size: 11px;
      fill: #1e2945;
      font-weight: 600;
    }
    .temp-hot { fill: #ef4444; font-weight: 700; font-size: 11px; }
    .temp-cool { fill: #0284c7; font-weight: 700; font-size: 11px; }
    .vapor-dot {
      transition: opacity 0.4s ease;
    }
    @keyframes riseSimple {
      0% { transform: translate(0, 0); opacity: 0; }
      20% { opacity: 0.8; }
      50% { transform: translate(0, -65px); opacity: 0.8; }
      100% { transform: translate(75px, -35px); opacity: 0; }
    }
    @keyframes riseFractional {
      0% { transform: translate(0, 0); opacity: 0; }
      20% { opacity: 0.8; }
      60% { transform: translate(0, -125px); opacity: 0.8; }
      100% { transform: translate(75px, -95px); opacity: 0; }
    }
    .flow-simple {
      animation: riseSimple 2.8s infinite ease-in-out;
    }
    .flow-fractional {
      animation: riseFractional 3.6s infinite ease-in-out;
    }
  </style>
</head>
<body>
  <div class="header">
    <div class="title">Distillation Methods</div>
    <div class="btn-group">
      <button class="btn active" id="btnBoth" onclick="setView('both')">Side-by-Side</button>
      <button class="btn" id="btnFocus" onclick="toggleVapor()">Animate Vapor</button>
    </div>
  </div>

  <div class="svg-container">
    <svg viewBox="0 0 760 480" xmlns="http://www.w3.org/2000/svg">
      <defs>
        
        <linearGradient id="coolWaterGrad" x1="0%" y1="0%" x2="100%" y2="100%">
          <stop offset="0%" stop-color="#bfdbfe" stop-opacity="0.8"/>
          <stop offset="100%" stop-color="#93c5fd" stop-opacity="0.8"/>
        </linearGradient>
        <linearGradient id="columnGrad" x1="0%" y1="100%" x2="0%" y2="0%">
          <stop offset="0%" stop-color="#fee2e2"/>
          <stop offset="50%" stop-color="#fef3c7"/>
          <stop offset="100%" stop-color="#e0f2fe"/>
        </linearGradient>
        <linearGradient id="heatGrad" x1="0%" y1="100%" x2="0%" y2="0%">
          <stop offset="0%" stop-color="#f97316"/>
          <stop offset="60%" stop-color="#eab308"/>
          <stop offset="100%" stop-color="#fef08a"/>
        </linearGradient>
        <linearGradient id="beadGrad" x1="0%" y1="0%" x2="100%" y2="100%">
          <stop offset="0%" stop-color="#ffffff"/>
          <stop offset="100%" stop-color="#cbd5e1"/>
        </linearGradient>

        <marker id="arrow" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
          <path d="M 0 1.5 L 8 5 L 0 8.5 z" fill="#64748b"/>
        </marker>
        <marker id="arrow-blue" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="5" markerHeight="5" orient="auto-start-reverse">
          <path d="M 0 1.5 L 8 5 L 0 8.5 z" fill="#0284c7"/>
        </marker>
      </defs>

      
      <line x1="380" y1="20" x2="380" y2="460" stroke="#e2e8f0" stroke-width="1.5" stroke-dasharray="5 5" />

      
      <g id="simple-panel">
        
        <text x="190" y="34" text-anchor="middle" class="label" font-size="15" fill="#1e2945">Simple Distillation</text>
        <rect x="60" y="48" width="260" height="24" rx="12" fill="#eff6ff" stroke="#bfdbfe" stroke-width="1" />
        <text x="190" y="64" text-anchor="middle" class="badge-text" fill="#1d4ed8">Use: ΔT_b &gt; 25–50°C or Solid + Liquid</text>

        
        <path d="M 125 435 L 155 435 L 143 395 L 137 395 Z" fill="#94a3b8" />
        <path d="M 134 395 Q 140 365 140 360 Q 140 365 146 395 Z" fill="url(#heatGrad)" opacity="0.9" />
        <path d="M 137 395 Q 140 375 140 370 Q 140 375 143 395 Z" fill="#ffffff" opacity="0.7" />

        
        <line x1="70" y1="440" x2="160" y2="440" stroke="#64748b" stroke-width="4" stroke-linecap="round"/>
        <line x1="85" y1="440" x2="85" y2="230" stroke="#94a3b8" stroke-width="3.5" />
        <line x1="85" y1="340" x2="115" y2="340" stroke="#64748b" stroke-width="2.5" />

        
        <circle cx="140" cy="330" r="32" fill="#f8fafc" stroke="#334155" stroke-width="2.5" />
        
        <path d="M 111 340 A 32 32 0 0 0 169 340 Z" fill="#93c5fd" opacity="0.6" />
        <line x1="110" y1="340" x2="170" y2="340" stroke="#3b82f6" stroke-width="1" />
        
        
        <rect x="132" y="255" width="16" height="48" fill="#f8fafc" stroke="#334155" stroke-width="2.5" stroke-dasharray="0 16 48 0" />
        <path d="M 132 295 L 132 255 L 148 255 L 148 295" fill="none" stroke="#334155" stroke-width="2.5" />

        
        <path d="M 132 255 L 132 225 L 148 225 L 148 245 L 180 262 L 174 274 L 148 260 L 148 255" fill="#f8fafc" stroke="#334155" stroke-width="2" />
        <rect x="135" y="218" width="10" height="7" fill="#dc2626" rx="2" />

        
        <line x1="140" y1="216" x2="140" y2="258" stroke="#ef4444" stroke-width="2.5" stroke-linecap="round" />
        <circle cx="140" cy="260" r="2.5" fill="#ef4444" />
        <text x="96" y="222" class="sublabel" font-size="10">Thermometer</text>
        <line x1="126" y1="225" x2="137" y2="232" stroke="#94a3b8" stroke-width="1" marker-end="url(#arrow)" />

        
        <g transform="rotate(30, 177, 268)">
          
          <rect x="177" y="256" width="110" height="24" rx="4" fill="url(#coolWaterGrad)" stroke="#38bdf8" stroke-width="1.5" />
          
          <rect x="165" y="264" width="135" height="8" fill="#ffffff" stroke="#334155" stroke-width="2" />
          
          <rect x="265" y="280" width="8" height="10" fill="#bae6fd" stroke="#38bdf8" stroke-width="1" />
          <rect x="195" y="246" width="8" height="10" fill="#bae6fd" stroke="#38bdf8" stroke-width="1" />
        </g>

        
        <text x="276" y="360" class="sublabel" fill="#0284c7" font-weight="600">Water in</text>
        <path d="M 270 354 L 260 340" fill="none" stroke="#0284c7" stroke-width="1.2" marker-end="url(#arrow-blue)" />

        <text x="206" y="242" class="sublabel" fill="#0284c7" font-weight="600">Water out</text>
        <path d="M 218 248 L 222 260" fill="none" stroke="#0284c7" stroke-width="1.2" marker-end="url(#arrow-blue)" />

        
        <path d="M 285 330 L 295 352 L 295 385" fill="none" stroke="#334155" stroke-width="2" />
        
        <path d="M 278 385 L 278 435 Q 278 440 283 440 L 317 440 Q 322 440 322 435 L 322 385" fill="#f8fafc" stroke="#334155" stroke-width="2" />
        
        <path d="M 279 415 L 279 435 Q 279 439 284 439 L 316 439 Q 321 439 321 435 L 321 415 Z" fill="#38bdf8" opacity="0.6" />
        <line x1="279" y1="415" x2="321" y2="415" stroke="#0284c7" stroke-width="1" />

        
        <text x="300" y="460" text-anchor="middle" class="label">Pure Distillate</text>
        <text x="140" y="460" text-anchor="middle" class="sublabel">Heat Source</text>
        <text x="245" y="295" text-anchor="middle" class="label" fill="#0369a1">Condenser</text>

        
        <g id="vaporSimpleGroup" class="flow-simple">
          <circle cx="140" cy="310" r="3.5" fill="#3b82f6" opacity="0.8"/>
          <circle cx="140" cy="275" r="3.5" fill="#3b82f6" opacity="0.8"/>
          <circle cx="152" cy="245" r="3" fill="#3b82f6" opacity="0.8"/>
        </g>
      </g>


      
      <g id="fractional-panel">
        
        <text x="570" y="34" text-anchor="middle" class="label" font-size="15" fill="#1e2945">Fractional Distillation</text>
        <rect x="435" y="48" width="270" height="24" rx="12" fill="#fef2f2" stroke="#fecaca" stroke-width="1" />
        <text x="570" y="64" text-anchor="middle" class="badge-text" fill="#b91c1c">Use: Close Boiling Points (ΔT_b &lt; 25°C)</text>

        
        <path d="M 505 435 L 535 435 L 523 395 L 517 395 Z" fill="#94a3b8" />
        <path d="M 514 395 Q 520 365 520 360 Q 520 365 526 395 Z" fill="url(#heatGrad)" opacity="0.9" />
        <path d="M 517 395 Q 520 375 520 370 Q 520 375 523 395 Z" fill="#ffffff" opacity="0.7" />

        
        <line x1="450" y1="440" x2="540" y2="440" stroke="#64748b" stroke-width="4" stroke-linecap="round"/>
        <line x1="465" y1="440" x2="465" y2="150" stroke="#94a3b8" stroke-width="3.5" />

        
        <circle cx="520" cy="330" r="32" fill="#f8fafc" stroke="#334155" stroke-width="2.5" />
        
        <path d="M 491 340 A 32 32 0 0 0 549 340 Z" fill="#c084fc" opacity="0.6" />
        <line x1="490" y1="340" x2="550" y2="340" stroke="#9333ea" stroke-width="1" />

        
        <rect x="510" y="165" width="20" height="135" fill="url(#columnGrad)" stroke="#334155" stroke-width="2" rx="1"/>

        
        <g fill="url(#beadGrad)" stroke="#64748b" stroke-width="0.8">
          <circle cx="516" cy="290" r="3.5" /><circle cx="524" cy="290" r="3.5" />
          <circle cx="520" cy="282" r="3.5" /><circle cx="515" cy="274" r="3.5" /><circle cx="525" cy="274" r="3.5" />
          <circle cx="520" cy="266" r="3.5" /><circle cx="515" cy="258" r="3.5" /><circle cx="525" cy="258" r="3.5" />
          <circle cx="520" cy="250" r="3.5" /><circle cx="515" cy="242" r="3.5" /><circle cx="525" cy="242" r="3.5" />
          <circle cx="520" cy="234" r="3.5" /><circle cx="515" cy="226" r="3.5" /><circle cx="525" cy="226" r="3.5" />
          <circle cx="520" cy="218" r="3.5" /><circle cx="515" cy="210" r="3.5" /><circle cx="525" cy="210" r="3.5" />
          <circle cx="520" cy="202" r="3.5" /><circle cx="515" cy="194" r="3.5" /><circle cx="525" cy="194" r="3.5" />
          <circle cx="520" cy="186" r="3.5" /><circle cx="515" cy="178" r="3.5" /><circle cx="525" cy="178" r="3.5" />
          <circle cx="520" cy="170" r="3" />
        </g>

        
        <path d="M 498 174 L 498 290" fill="none" stroke="#94a3b8" stroke-width="1.5" marker-start="url(#arrow)" marker-end="url(#arrow)" />
        <text x="492" y="176" text-anchor="end" class="temp-cool">Cooler</text>
        <text x="492" y="294" text-anchor="end" class="temp-hot">Hotter</text>

        
        <g transform="translate(392, 190)">
          <rect x="0" y="0" width="102" height="42" rx="6" fill="#ffffff" stroke="#94a3b8" stroke-width="1" filter="drop-shadow(0 2px 4px rgba(0,0,0,0.06))"/>
          <text x="51" y="15" text-anchor="middle" class="badge-text" font-size="10" fill="#1e2945">Glass Beads</text>
          <text x="51" y="27" text-anchor="middle" class="sublabel" font-size="9" fill="#475569">Repeated cycles</text>
          <text x="51" y="37" text-anchor="middle" class="sublabel" font-size="8.5" fill="#64748b">Vaporise ⇌ Condense</text>
          
          <polygon points="102,20 114,24 102,28" fill="#ffffff" stroke="#94a3b8" stroke-width="1" />
          <line x1="101" y1="20.5" x2="101" y2="27.5" stroke="#ffffff" stroke-width="1.5" />
        </g>

        
        <path d="M 512 165 L 512 135 L 528 135 L 528 155 L 560 172 L 554 184 L 528 170 L 528 165" fill="#f8fafc" stroke="#334155" stroke-width="2" />
        <rect x="515" y="128" width="10" height="7" fill="#dc2626" rx="2" />
        <line x1="520" y1="126" x2="520" y2="168" stroke="#ef4444" stroke-width="2.5" stroke-linecap="round" />
        <circle cx="520" cy="170" r="2.5" fill="#ef4444" />

        
        <g transform="rotate(30, 557, 178)">
          <rect x="557" y="166" width="110" height="24" rx="4" fill="url(#coolWaterGrad)" stroke="#38bdf8" stroke-width="1.5" />
          <rect x="545" y="174" width="135" height="8" fill="#ffffff" stroke="#334155" stroke-width="2" />
          <rect x="645" y="190" width="8" height="10" fill="#bae6fd" stroke="#38bdf8" stroke-width="1" />
          <rect x="575" y="156" width="8" height="10" fill="#bae6fd" stroke="#38bdf8" stroke-width="1" />
        </g>

        
        <path d="M 665 240 L 675 262 L 675 385" fill="none" stroke="#334155" stroke-width="2" />
        
        <path d="M 658 385 L 658 435 Q 658 440 663 440 L 697 440 Q 702 440 702 435 L 702 385" fill="#f8fafc" stroke="#334155" stroke-width="2" />
        <path d="M 659 410 L 659 435 Q 659 439 664 439 L 696 439 Q 701 439 701 435 L 701 410 Z" fill="#a855f7" opacity="0.6" />
        <line x1="659" y1="410" x2="701" y2="410" stroke="#7e22ce" stroke-width="1" />

        
        <text x="680" y="460" text-anchor="middle" class="label">Lowest B.P. Liquid</text>
        <text x="520" y="460" text-anchor="middle" class="sublabel">Heat Source</text>
        <text x="585" y="148" text-anchor="start" class="label" fill="#1e2945">Fractionating Column</text>

        
        <g id="vaporFractGroup" class="flow-fractional">
          <circle cx="520" cy="305" r="3.5" fill="#a855f7" opacity="0.8"/>
          <circle cx="520" cy="245" r="3.5" fill="#a855f7" opacity="0.8"/>
          <circle cx="520" cy="180" r="3.5" fill="#a855f7" opacity="0.8"/>
          <circle cx="532" cy="155" r="3" fill="#a855f7" opacity="0.8"/>
        </g>
      </g>
    </svg>
  </div>

  <script>
    let isAnimated = true;

    function toggleVapor() {
      isAnimated = !isAnimated;
      const simpleFlow = document.getElementById('vaporSimpleGroup');
      const fractFlow = document.getElementById('vaporFractGroup');
      const btn = document.getElementById('btnFocus');

      if (isAnimated) {
        simpleFlow.style.animationPlayState = 'running';
        fractFlow.style.animationPlayState = 'running';
        btn.classList.add('active');
        btn.textContent = 'Pause Vapor';
      } else {
        simpleFlow.style.animationPlayState = 'paused';
        fractFlow.style.animationPlayState = 'paused';
        btn.classList.remove('active');
        btn.textContent = 'Animate Vapor';
      }
    }

    function setView(mode) {
      const simple = document.getElementById('simple-panel');
      const fract = document.getElementById('fractional-panel');
      const btnBoth = document.getElementById('btnBoth');
      
      simple.style.opacity = '1';
      fract.style.opacity = '1';
      btnBoth.classList.add('active');
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <link rel="stylesheet" href="{{VENDOR_CDN}}/katex.min.css" />
  <script src="{{VENDOR_CDN}}/katex.min.js"></script>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #f8fafc;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 12px;
    }

    .main-layout {
      display: flex;
      flex-direction: row;
      align-items: center;
      justify-content: center;
      gap: 16px;
      width: 100%;
      max-width: 620px;
      flex: 1;
    }

    @media (max-width: 500px) {
      .main-layout {
        flex-direction: column;
        gap: 10px;
      }
    }

    /* Diagram SVG container */
    .visual-pane {
      position: relative;
      width: 220px;
      height: 310px;
      flex-shrink: 0;
    }

    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    /* Info / Formula card */
    .formula-pane {
      display: flex;
      flex-direction: column;
      gap: 8px;
      flex: 1;
      min-width: 220px;
      max-width: 320px;
    }

    .info-box {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 10px 12px;
      box-shadow: 0 1px 3px rgba(0,0,0,0.04);
      font-size: 13px;
    }

    .formula-display {
      text-align: center;
      padding: 6px 0;
      font-size: 14px;
    }

    .calc-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-size: 12px;
      padding: 3px 0;
      border-top: 1px solid #f1f5f9;
    }

    .calc-row:first-of-type {
      border-top: none;
    }

    .dot-badge {
      display: inline-block;
      width: 10px;
      height: 10px;
      border-radius: 50%;
      margin-right: 6px;
      vertical-align: middle;
    }

    /* Controls */
    .controls-bar {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      width: 100%;
      max-width: 480px;
      margin-top: 8px;
      flex-wrap: wrap;
    }

    .step-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 6px 12px;
      font-size: 12px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: all 0.2s ease;
    }

    .step-btn:hover {
      background: #f1f5f9;
      color: #0f172a;
    }

    .step-btn.active {
      background: #0284c7;
      border-color: #0284c7;
      color: #ffffff;
    }

    .play-btn {
      background: #e0f2fe;
      border: 1px solid #7dd3fc;
      color: #0369a1;
      padding: 6px 12px;
      border-radius: 6px;
      font-size: 12px;
      font-weight: 600;
      cursor: pointer;
    }

    /* SVG Transitions */
    .smooth {
      transition: all 0.7s cubic-bezier(0.4, 0, 0.2, 1);
    }
  </style>
</head>
<body>

  <div class="main-layout">
    
    <div class="visual-pane">
      <svg viewBox="0 0 220 310" xmlns="http://www.w3.org/2000/svg">
        <defs>
          <marker id="arr" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
            <path d="M 0 1.5 L 10 5 L 0 8.5 z" fill="#64748b" />
          </marker>
          <marker id="arr-blue" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
            <path d="M 0 1.5 L 10 5 L 0 8.5 z" fill="#2563eb" />
          </marker>
          <marker id="arr-yellow" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="4" markerHeight="4" orient="auto-start-reverse">
            <path d="M 0 1.5 L 10 5 L 0 8.5 z" fill="#d97706" />
          </marker>
          <linearGradient id="wetPaper" x1="0%" y1="100%" x2="0%" y2="0%">
            <stop offset="0%" stop-color="#e0f2fe" stop-opacity="0.8"/>
            <stop offset="100%" stop-color="#f8fafc" stop-opacity="0.5"/>
          </linearGradient>
        </defs>

        
        <rect x="25" y="40" width="130" height="250" rx="10" fill="#f8fafc" stroke="#94a3b8" stroke-width="2" stroke-dasharray="none" />
        <rect x="23" y="38" width="134" height="6" rx="3" fill="#cbd5e1" />
        <line x1="20" y1="40" x2="30" y2="40" stroke="#94a3b8" stroke-width="2" />

        
        <path d="M 26 270 Q 90 268 154 270 L 154 285 Q 154 290 145 290 L 35 290 Q 26 290 26 285 Z" fill="#bae6fd" opacity="0.6"/>
        <text x="32" y="284" font-size="9" fill="#0369a1" font-weight="600">Solvent</text>

        
        <rect x="50" y="20" width="80" height="265" fill="#ffffff" stroke="#cbd5e1" stroke-width="1.5" />
        
        <rect id="wetZone" class="smooth" x="50" y="285" width="80" height="0" fill="url(#wetPaper)" />

        
        <line x1="50" y1="250" x2="130" y2="250" stroke="#94a3b8" stroke-width="1.5" stroke-dasharray="3 2" />
        <text x="134" y="253" font-size="9" fill="#64748b" font-weight="500">Origin</text>

        
        <g id="frontGroup" class="smooth" opacity="0" transform="translate(0, 0)">
          <line x1="50" y1="90" x2="130" y2="90" stroke="#0284c7" stroke-width="1.5" stroke-dasharray="3 2" />
          <text x="134" y="93" font-size="9" fill="#0284c7" font-weight="600">Solvent Front</text>
        </g>

        
        
        <circle id="spotMix" class="smooth" cx="90" cy="250" r="5" fill="#9333ea" opacity="1" />

        
        <ellipse id="spotBlue" class="smooth" cx="90" cy="250" rx="4.5" ry="5.5" fill="#2563eb" opacity="0" />

        
        <ellipse id="spotYellow" class="smooth" cx="90" cy="250" rx="4.5" ry="5.5" fill="#eab308" stroke="#ca8a04" stroke-width="0.5" opacity="0" />

        
        <g id="dimSolvent" class="smooth" opacity="0">
          <line x1="42" y1="250" x2="42" y2="90" stroke="#64748b" stroke-width="1.2" marker-start="url(#arr)" marker-end="url(#arr)" />
          <line x1="40" y1="250" x2="44" y2="250" stroke="#64748b" stroke-width="1.2" />
          <line x1="40" y1="90" x2="52" y2="90" stroke="#64748b" stroke-width="1.2" />
          <text x="36" y="174" font-size="11" fill="#475569" font-weight="700" text-anchor="end">b</text>
        </g>

        <g id="dimYellow" class="smooth" opacity="0">
          <line x1="102" y1="250" x2="102" y2="122" stroke="#d97706" stroke-width="1.2" marker-start="url(#arr-yellow)" marker-end="url(#arr-yellow)" />
          <text x="106" y="190" font-size="10" fill="#d97706" font-weight="700">a₁</text>
        </g>

        <g id="dimBlue" class="smooth" opacity="0">
          <line x1="78" y1="250" x2="78" y2="202" stroke="#2563eb" stroke-width="1.2" marker-start="url(#arr-blue)" marker-end="url(#arr-blue)" />
          <text x="70" y="230" font-size="10" fill="#2563eb" font-weight="700">a₂</text>
        </g>
      </svg>
    </div>

    
    <div class="formula-pane">
      <div class="info-box">
        <div id="formulaBox" class="formula-display"></div>
      </div>

      <div class="info-box">
        <div class="calc-row">
          <span><span class="dot-badge" style="background:#eab308;"></span><b>Yellow spot:</b></span>
          <span id="rfYellow">High mobile affinity</span>
        </div>
        <div class="calc-row">
          <span><span class="dot-badge" style="background:#2563eb;"></span><b>Blue spot:</b></span>
          <span id="rfBlue">High paper affinity</span>
        </div>
      </div>
    </div>
  </div>

  
  <div class="controls-bar">
    <button class="step-btn active" data-step="0">1. Setup</button>
    <button class="step-btn" data-step="1">2. Developing</button>
    <button class="step-btn" data-step="2">3. Separated</button>
    <button class="step-btn" data-step="3">4. Calculate R<sub>f</sub></button>
    <button id="playBtn" class="play-btn">⏸ Pause</button>
  </div>

  <script>
    const steps = [
      {
        wetY: 285, wetH: 0,
        frontOpacity: 0,
        mixOpacity: 1, mixY: 250,
        blueOpacity: 0, blueY: 250,
        yellowOpacity: 0, yellowY: 250,
        dimSolvent: 0, dimYellow: 0, dimBlue: 0,
        yellowNote: "High mobile affinity",
        blueNote: "High paper affinity"
      },
      {
        wetY: 170, wetH: 115,
        frontOpacity: 1,
        mixOpacity: 0.2, mixY: 250,
        blueOpacity: 0.9, blueY: 226,
        yellowOpacity: 0.9, yellowY: 186,
        dimSolvent: 0, dimYellow: 0, dimBlue: 0,
        yellowNote: "Moving fast",
        blueNote: "Moving slow"
      },
      {
        wetY: 90, wetH: 195,
        frontOpacity: 1,
        mixOpacity: 0, mixY: 250,
        blueOpacity: 1, blueY: 202,
        yellowOpacity: 1, yellowY: 122,
        dimSolvent: 0, dimYellow: 0, dimBlue: 0,
        yellowNote: "Higher solubility",
        blueNote: "Stronger adsorption"
      },
      {
        wetY: 90, wetH: 195,
        frontOpacity: 1,
        mixOpacity: 0, mixY: 250,
        blueOpacity: 1, blueY: 202,
        yellowOpacity: 1, yellowY: 122,
        dimSolvent: 1, dimYellow: 1, dimBlue: 1,
        yellowNote: "R_f = 0.80",
        blueNote: "R_f = 0.30"
      }
    ];

    let currentStep = 0;
    let timer = null;
    let isPlaying = true;

    // Elements
    const wetZone = document.getElementById('wetZone');
    const frontGroup = document.getElementById('frontGroup');
    const spotMix = document.getElementById('spotMix');
    const spotBlue = document.getElementById('spotBlue');
    const spotYellow = document.getElementById('spotYellow');
    const dimSolvent = document.getElementById('dimSolvent');
    const dimYellow = document.getElementById('dimYellow');
    const dimBlue = document.getElementById('dimBlue');
    const rfYellow = document.getElementById('rfYellow');
    const rfBlue = document.getElementById('rfBlue');
    const formulaBox = document.getElementById('formulaBox');
    const stepButtons = document.querySelectorAll('.step-btn');
    const playBtn = document.getElementById('playBtn');

    // Render Math via KaTeX
    function renderMath() {
      try {
        katex.render(
          "R_f = \\frac{\\text{Distance by substance } (a)}{\\text{Distance by solvent } (b)}",
          formulaBox,
          { displayMode: false, throwOnError: false }
        );
      } catch (e) {
        formulaBox.innerHTML = "<b>R<sub>f</sub></b> = Distance by substance (a) / Distance by solvent (b)";
      }
    }
    renderMath();

    function applyStep(index) {
      currentStep = index;
      const s = steps[index];

      // Update SVG
      wetZone.setAttribute('y', s.wetY);
      wetZone.setAttribute('height', s.wetH);

      frontGroup.style.opacity = s.frontOpacity;
      
      spotMix.style.opacity = s.mixOpacity;
      spotMix.setAttribute('cy', s.mixY);

      spotBlue.style.opacity = s.blueOpacity;
      spotBlue.setAttribute('cy', s.blueY);

      spotYellow.style.opacity = s.yellowOpacity;
      spotYellow.setAttribute('cy', s.yellowY);

      dimSolvent.style.opacity = s.dimSolvent;
      dimYellow.style.opacity = s.dimYellow;
      dimBlue.style.opacity = s.dimBlue;

      // Update Text
      rfYellow.textContent = s.yellowNote;
      rfBlue.textContent = s.blueNote;

      // Update Button State
      stepButtons.forEach((btn, i) => {
        btn.classList.toggle('active', i === index);
      });
    }

    function nextStep() {
      const next = (currentStep + 1) % steps.length;
      applyStep(next);
    }

    function startTimer() {
      if (timer) clearInterval(timer);
      timer = setInterval(nextStep, 3500);
      isPlaying = true;
      playBtn.textContent = "⏸ Pause";
    }

    function pauseTimer() {
      if (timer) clearInterval(timer);
      isPlaying = false;
      playBtn.textContent = "▶ Play";
    }

    // Event Listeners
    stepButtons.forEach((btn) => {
      btn.addEventListener('click', () => {
        const stepIdx = parseInt(btn.getAttribute('data-step'), 10);
        applyStep(stepIdx);
        pauseTimer();
      });
    });

    playBtn.addEventListener('click', () => {
      if (isPlaying) {
        pauseTimer();
      } else {
        nextStep();
        startTimer();
      }
    });

    // Initialize
    applyStep(0);
    startTimer();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <title>Separation Pathway Flowchart</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    }

    body {
      background: #f8fafc;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    /* Top Mixture Pill */
    .mixture-bar {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 999px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 700;
      color: #475569;
      display: flex;
      align-items: center;
      gap: 6px;
      margin-bottom: 10px;
    }

    .mixture-bar span {
      display: inline-block;
      padding: 2px 6px;
      border-radius: 6px;
      font-size: 12px;
      font-weight: 600;
    }
    .tag-iron { background: #e2e8f0; color: #334155; }
    .tag-sand { background: #fef3c7; color: #92400e; }
    .tag-salt { background: #e0f2fe; color: #0369a1; }
    .tag-eth { background: #fce7f3; color: #9d174d; }
    .tag-wat { background: #dcfce7; color: #166534; }

    /* Flowchart Grid */
    .grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 10px;
      width: 100%;
      max-width: 620px;
    }

    @media (max-width: 480px) {
      .grid {
        grid-template-columns: 1fr;
        gap: 8px;
      }
    }

    .step-card {
      background: #ffffff;
      border-radius: 12px;
      padding: 10px 12px;
      border: 2px solid transparent;
      box-shadow: 0 1px 3px rgba(0,0,0,0.06);
      transition: border-color 0.25s ease, box-shadow 0.25s ease, opacity 0.25s ease;
      cursor: pointer;
      display: flex;
      flex-direction: column;
      gap: 6px;
      position: relative;
    }

    .step-card.active {
      border-color: #22b7ff;
      box-shadow: 0 4px 14px rgba(34, 183, 255, 0.25);
    }

    .step-card:not(.active) {
      opacity: 0.7;
    }

    .step-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .step-num {
      background: #f1f5f9;
      color: #475569;
      font-size: 11px;
      font-weight: 800;
      padding: 2px 6px;
      border-radius: 6px;
    }

    .step-card.active .step-num {
      background: #22b7ff;
      color: #ffffff;
    }

    .property-badge {
      font-size: 11px;
      font-weight: 700;
      padding: 2px 8px;
      border-radius: 999px;
      text-transform: uppercase;
      letter-spacing: 0.3px;
    }

    .prop-mag { background: #fee2e2; color: #991b1b; }
    .prop-bp { background: #fdf2f8; color: #9d174d; }
    .prop-size { background: #fef3c7; color: #92400e; }
    .prop-sol { background: #e0f2fe; color: #075985; }

    .technique-row {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 700;
      color: #0f172a;
    }

    .tech-icon {
      font-size: 18px;
      line-height: 1;
    }

    .result-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f8fafc;
      padding: 6px 8px;
      border-radius: 8px;
      font-size: 12px;
      border: 1px dashed #cbd5e1;
    }

    .isolated-target {
      font-weight: 800;
      color: #059669;
      display: flex;
      align-items: center;
      gap: 4px;
    }

    .condition-text {
      color: #64748b;
      font-size: 11px;
      font-weight: 600;
    }

    /* Controls */
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      margin-top: 10px;
      width: 100%;
    }

    .btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      color: #334155;
      padding: 6px 14px;
      border-radius: 8px;
      font-size: 13px;
      font-weight: 700;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      user-select: none;
    }

    .btn:active {
      background: #f1f5f9;
    }

    .dots-container {
      display: flex;
      gap: 6px;
    }

    .dot {
      width: 9px;
      height: 9px;
      border-radius: 50%;
      background: #cbd5e1;
      cursor: pointer;
      transition: background-color 0.2s ease, transform 0.2s ease;
    }

    .dot.active {
      background: #22b7ff;
      transform: scale(1.25);
    }
  </style>
</head>
<body>

  
  <div class="mixture-bar">
    <span>Mixture:</span>
    <span class="tag-iron">Iron</span>
    <span class="tag-sand">Sand</span>
    <span class="tag-salt">Salt</span>
    <span class="tag-eth">Ethanol</span>
    <span class="tag-wat">Water</span>
  </div>

  
  <div class="grid">
    
    <div class="step-card active" data-step="0">
      <div class="step-header">
        <span class="step-num">STEP 1</span>
        <span class="property-badge prop-mag">Magnetism</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">🧲</span>
        <span>Magnetic Separation</span>
      </div>
      <div class="result-row">
        <span class="condition-text">Dry mixture</span>
        <span class="isolated-target">✓ Iron Filings</span>
      </div>
    </div>

    
    <div class="step-card" data-step="1">
      <div class="step-header">
        <span class="step-num">STEP 2</span>
        <span class="property-badge prop-bp">Boiling Point</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">⚗️</span>
        <span>Fractional Distillation</span>
      </div>
      <div class="result-row">
        <span class="condition-text">78°C vapor</span>
        <span class="isolated-target">✓ Pure Ethanol</span>
      </div>
    </div>

    
    <div class="step-card" data-step="2">
      <div class="step-header">
        <span class="step-num">STEP 3</span>
        <span class="property-badge prop-size">Particle Size</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">🧪</span>
        <span>Filtration</span>
      </div>
      <div class="result-row">
        <span class="condition-text">Filter paper</span>
        <span class="isolated-target">✓ Sand Residue</span>
      </div>
    </div>

    
    <div class="step-card" data-step="3">
      <div class="step-header">
        <span class="step-num">STEP 4</span>
        <span class="property-badge prop-sol">Solubility</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">🧂</span>
        <span>Crystallisation</span>
      </div>
      <div class="result-row">
        <span class="condition-text">Evaporate &amp; cool</span>
        <span class="isolated-target">✓ Pure Salt</span>
      </div>
    </div>
  </div>

  
  <div class="controls">
    <button class="btn" id="prevBtn">← Prev</button>
    <div class="dots-container">
      <div class="dot active" data-step="0"></div>
      <div class="dot" data-step="1"></div>
      <div class="dot" data-step="2"></div>
      <div class="dot" data-step="3"></div>
    </div>
    <button class="btn" id="nextBtn">Next →</button>
    <button class="btn" id="playBtn">⏸ Pause</button>
  </div>

  <script src="{{VENDOR_CDN}}/classace-diagram.js"></script>
  <script>
    const cards = $$('.step-card');
    const dots = $$('.dot');
    const playBtn = $('#playBtn');

    let currentStep = 0;
    let isPlaying = true;
    let autoTimer = null;

    function setStep(idx) {
      currentStep = (idx + cards.length) % cards.length;
      cards.forEach((c, i) => c.classList.toggle('active', i === currentStep));
      dots.forEach((d, i) => d.classList.toggle('active', i === currentStep));
    }

    function startAuto() {
      stopAuto();
      autoTimer = setInterval(() => {
        setStep(currentStep + 1);
      }, 3500);
      isPlaying = true;
      playBtn.textContent = '⏸ Pause';
    }

    function stopAuto() {
      if (autoTimer) clearInterval(autoTimer);
      autoTimer = null;
      isPlaying = false;
      playBtn.textContent = '▶ Play';
    }

    // Direct card taps
    cards.forEach((card, i) => {
      onTap(card, () => {
        setStep(i);
        stopAuto();
      });
    });

    // Dot taps
    dots.forEach((dot, i) => {
      onTap(dot, () => {
        setStep(i);
        stopAuto();
      });
    });

    // Control buttons
    onTap($('#prevBtn'), () => {
      setStep(currentStep - 1);
      stopAuto();
    });

    onTap($('#nextBtn'), () => {
      setStep(currentStep + 1);
      stopAuto();
    });

    onTap(playBtn, () => {
      if (isPlaying) {
        stopAuto();
      } else {
        startAuto();
      }
    });

    // Initialize auto-play
    startAuto();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    }

    body {
      background-color: #f8f9fa;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      user-select: none;
      -webkit-user-select: none;
    }

    .header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 0 4px;
    }

    .title {
      font-size: 14px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #1e2945;
    }

    .subtitle {
      font-size: 12px;
      color: #64748b;
      font-weight: 500;
    }

    .grid {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .tile {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 8px 12px;
      display: grid;
      grid-template-columns: 100px 32px 1fr 110px;
      align-items: center;
      gap: 8px;
      cursor: pointer;
      transition: border-color 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
      box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
    }

    @media (max-width: 480px) {
      .tile {
        grid-template-columns: 85px 24px 1fr 90px;
        padding: 6px 8px;
        gap: 6px;
      }
    }

    .tile.active {
      border-color: #0284c7;
      box-shadow: 0 0 0 2px rgba(2, 132, 199, 0.15), 0 2px 6px rgba(0, 0, 0, 0.06);
      background-color: #f0f9ff;
    }

    .prop-col {
      display: flex;
      flex-direction: column;
    }

    .prop-label {
      font-size: 11px;
      text-transform: uppercase;
      font-weight: 700;
      color: #64748b;
      letter-spacing: 0.3px;
    }

    .prop-name {
      font-size: 13px;
      font-weight: 700;
      color: #1e2945;
      line-height: 1.2;
    }

    .arrow-col {
      display: flex;
      align-items: center;
      justify-content: center;
      color: #94a3b8;
      font-size: 14px;
      font-weight: bold;
    }

    .tile.active .arrow-col {
      color: #0284c7;
    }

    .diagram-col {
      display: flex;
      align-items: center;
      justify-content: center;
      height: 48px;
      background: #f8fafc;
      border-radius: 8px;
      padding: 4px 6px;
      overflow: hidden;
    }

    .tile.active .diagram-col {
      background: #ffffff;
    }

    .tech-col {
      display: flex;
      flex-direction: column;
      align-items: flex-end;
      text-align: right;
    }

    .tech-name {
      font-size: 13px;
      font-weight: 700;
      color: #0284c7;
      line-height: 1.2;
    }

    .tech-tag {
      font-size: 10px;
      font-weight: 600;
      color: #475569;
      background: #e2e8f0;
      padding: 2px 6px;
      border-radius: 999px;
      margin-top: 3px;
      white-space: nowrap;
    }

    .tile.active .tech-tag {
      background: #bae6fd;
      color: #0369a1;
    }

    /* SVG Diagram Styling */
    svg {
      width: 100%;
      height: 100%;
      max-height: 42px;
    }

    .drop-anim {
      animation: drip 1.5s infinite ease-in;
    }

    @keyframes drip {
      0% { transform: translateY(0); opacity: 0; }
      50% { opacity: 1; }
      100% { transform: translateY(12px); opacity: 0; }
    }

    .vapor-anim {
      animation: rise 1.8s infinite ease-out;
    }

    @keyframes rise {
      0% { transform: translateY(0); opacity: 0.8; }
      100% { transform: translateY(-10px); opacity: 0; }
    }

    .flow-anim {
      stroke-dasharray: 4, 4;
      animation: flow 1.2s linear infinite;
    }

    @keyframes flow {
      to { stroke-dashoffset: -8; }
    }

    .spot-anim {
      animation: spotPulse 2s infinite alternate ease-in-out;
    }

    @keyframes spotPulse {
      0% { opacity: 0.7; }
      100% { opacity: 1; }
    }

    .info-bar {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 8px 12px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-size: 12px;
      font-weight: 600;
      color: #1e2945;
    }

    .info-desc {
      color: #475569;
      font-weight: 500;
    }
  </style>
</head>
<body>

  <div class="header">
    <span class="title">Physical Separation Matrix</span>
    <span class="subtitle">Tap any property</span>
  </div>

  <div class="grid" id="tilesContainer">

    
    <div class="tile active" data-index="0" data-info="Separates insoluble solids from a liquid via particle size exclusion.">
      <div class="prop-col">
        <span class="prop-label">Property</span>
        <span class="prop-name">Particle<br>Size</span>
      </div>
      <div class="arrow-col">→</div>
      <div class="diagram-col">
        <svg viewBox="0 0 160 44">
          
          <polygon points="35,6 75,6 60,26 60,40 50,40 50,26" fill="none" stroke="#64748b" stroke-width="2" stroke-linejoin="round" />
          <line x1="38" y1="8" x2="72" y2="8" stroke="#cbd5e1" stroke-width="1.5" stroke-dasharray="2,2"/>
          
          <circle cx="50" cy="12" r="3.5" fill="#d97706" />
          <circle cx="58" cy="10" r="4" fill="#d97706" />
          <circle cx="62" cy="15" r="3" fill="#d97706" />
          
          <circle class="drop-anim" cx="55" cy="30" r="2.5" fill="#0284c7" />
          
          <path d="M100,16 L100,38 Q100,42 105,42 L135,42 Q140,42 140,38 L140,16" fill="none" stroke="#64748b" stroke-width="2" />
          
          <rect x="102" y="28" width="36" height="12" rx="2" fill="#bae6fd" opacity="0.8" />
        </svg>
      </div>
      <div class="tech-col">
        <span class="tech-name">Filtration</span>
        <span class="tech-tag">Insoluble Solid</span>
      </div>
    </div>

    
    <div class="tile" data-index="1" data-info="Recovers dissolved solids by evaporating solvent until solute crystallises.">
      <div class="prop-col">
        <span class="prop-label">Property</span>
        <span class="prop-name">Solubility<br>in Solvent</span>
      </div>
      <div class="arrow-col">→</div>
      <div class="diagram-col">
        <svg viewBox="0 0 160 44">
          
          <path d="M35,16 Q55,34 75,16 Z" fill="#e2e8f0" stroke="#64748b" stroke-width="2" />
          
          <path d="M48,39 Q55,34 62,39" fill="none" stroke="#ef4444" stroke-width="2" stroke-linecap="round" />
          
          <path class="vapor-anim" d="M45,12 Q48,6 45,2" fill="none" stroke="#94a3b8" stroke-width="1.5" />
          <path class="vapor-anim" d="M65,12 Q68,6 65,2" fill="none" stroke="#94a3b8" stroke-width="1.5" style="animation-delay: 0.6s;" />
          
          <g transform="translate(100, 8)">
            <polygon points="18,6 26,14 18,22 10,14" fill="#0284c7" opacity="0.9" stroke="#0369a1" stroke-width="1"/>
            <polygon points="32,16 38,22 32,28 26,22" fill="#38bdf8" opacity="0.9" stroke="#0284c7" stroke-width="1"/>
            <polygon points="12,20 18,26 12,32 6,26" fill="#0ea5e9" opacity="0.9" stroke="#0284c7" stroke-width="1"/>
          </g>
        </svg>
      </div>
      <div class="tech-col">
        <span class="tech-name">Crystallisation</span>
        <span class="tech-tag">Dissolved Solute</span>
      </div>
    </div>

    
    <div class="tile" data-index="2" data-info="Separates miscible liquids based on differences in boiling points.">
      <div class="prop-col">
        <span class="prop-label">Property</span>
        <span class="prop-name">Boiling<br>Point (BP)</span>
      </div>
      <div class="arrow-col">→</div>
      <div class="diagram-col">
        <svg viewBox="0 0 160 44">
          
          <circle cx="35" cy="28" r="12" fill="#bae6fd" stroke="#64748b" stroke-width="2"/>
          <line x1="35" y1="8" x2="35" y2="16" stroke="#64748b" stroke-width="2.5"/>
          
          <line x1="35" y1="6" x2="35" y2="14" stroke="#ef4444" stroke-width="1.5"/>
          
          <path class="flow-anim" d="M35,12 L85,26" fill="none" stroke="#0284c7" stroke-width="2" />
          
          <rect x="46" y="10" width="32" height="12" rx="3" transform="rotate(15.5 46 10)" fill="#0ea5e9" opacity="0.25" stroke="#0284c7" stroke-width="1"/>
          
          <path d="M115,20 L115,38 Q115,41 119,41 L135,41 Q139,41 139,38 L139,20" fill="none" stroke="#64748b" stroke-width="2" />
          <rect x="117" y="28" width="20" height="11" fill="#0284c7" opacity="0.8" rx="2" />
        </svg>
      </div>
      <div class="tech-col">
        <span class="tech-name">Distillation</span>
        <span class="tech-tag">BP Difference</span>
      </div>
    </div>

    
    <div class="tile" data-index="3" data-info="Separates dissolved substances via mobile vs stationary phase affinity.">
      <div class="prop-col">
        <span class="prop-label">Property</span>
        <span class="prop-name">Phase<br>Affinity</span>
      </div>
      <div class="arrow-col">→</div>
      <div class="diagram-col">
        <svg viewBox="0 0 160 44">
          
          <rect x="50" y="4" width="60" height="36" rx="2" fill="#ffffff" stroke="#94a3b8" stroke-width="1.5" />
          
          <line x1="53" y1="34" x2="107" y2="34" stroke="#cbd5e1" stroke-width="1" stroke-dasharray="1,1"/>
          
          <line x1="53" y1="8" x2="107" y2="8" stroke="#38bdf8" stroke-width="1" stroke-dasharray="2,1"/>
          
          
          <circle class="spot-anim" cx="68" cy="13" r="3" fill="#ef4444" />
          
          <circle class="spot-anim" cx="80" cy="20" r="3" fill="#0284c7" style="animation-delay: 0.4s;" />
          
          <circle class="spot-anim" cx="92" cy="28" r="3" fill="#f59e0b" style="animation-delay: 0.8s;" />
        </svg>
      </div>
      <div class="tech-col">
        <span class="tech-name">Chromatography</span>
        <span class="tech-tag">Phase Partition</span>
      </div>
    </div>

  </div>

  
  <div class="info-bar">
    <span id="infoText" class="info-desc">Separates insoluble solids from a liquid via particle size exclusion.</span>
  </div>

  <script>
    const tiles = document.querySelectorAll('.tile');
    const infoText = document.getElementById('infoText');

    tiles.forEach(tile => {
      tile.addEventListener('click', () => {
        tiles.forEach(t => t.classList.remove('active'));
        tile.classList.add('active');
        infoText.textContent = tile.getAttribute('data-info');
      });
    });
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      padding: 8px 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      user-select: none;
    }

    .header-bar {
      width: 100%;
      max-width: 600px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 4px 8px;
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
    }

    .svg-container {
      width: 100%;
      max-width: 580px;
      position: relative;
    }

    svg {
      width: 100%;
      height: auto;
      display: block;
    }

    /* Hotspot Styling */
    .hotspot {
      cursor: pointer;
      transition: transform 0.2s ease;
    }
    .hotspot-pulse {
      animation: pulse 2s infinite;
      transform-origin: center;
    }
    @keyframes pulse {
      0% { r: 9; opacity: 0.8; }
      50% { r: 15; opacity: 0; }
      100% { r: 9; opacity: 0; }
    }
    .hotspot:hover .hotspot-circle,
    .hotspot.active .hotspot-circle {
      fill: #0284c7;
      stroke: #ffffff;
      stroke-width: 2px;
    }

    /* Vapor & Liquid Animation */
    .vapor-bubble {
      animation: rise 2.4s infinite ease-in-out;
    }
    .vapor-stream {
      stroke-dasharray: 6, 6;
      animation: flow 1.2s linear infinite;
    }
    .drop {
      animation: drip 1.6s infinite cubic-bezier(0.55, 0.085, 0.68, 0.53);
    }
    @keyframes rise {
      0% { transform: translateY(0); opacity: 0; }
      40% { opacity: 0.7; }
      100% { transform: translateY(-38px); opacity: 0; }
    }
    @keyframes flow {
      from { stroke-dashoffset: 24; }
      to { stroke-dashoffset: 0; }
    }
    @keyframes drip {
      0% { transform: translateY(0); opacity: 0; }
      30% { opacity: 1; }
      90% { transform: translateY(32px); opacity: 1; }
      100% { transform: translateY(34px); opacity: 0; }
    }

    /* Info Card */
    .info-card {
      width: 100%;
      max-width: 580px;
      min-height: 56px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 8px 14px;
      margin-top: 4px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .info-badge {
      background: #e0f2fe;
      color: #0369a1;
      font-size: 11px;
      font-weight: 700;
      padding: 3px 8px;
      border-radius: 12px;
      white-space: nowrap;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .info-text {
      font-size: 13px;
      line-height: 1.35;
      color: #1e2945;
      font-weight: 500;
    }

    /* Part highlight in SVG */
    .part-highlight {
      opacity: 0;
      transition: opacity 0.25s ease;
      pointer-events: none;
    }
    .part-highlight.active {
      opacity: 1;
    }
  </style>
</head>
<body>

  <div class="header-bar">
    <span>Simple Distillation Apparatus</span>
    <span style="font-size: 11px; color: #0284c7; font-weight: 700;">Tap hot-spots to inspect</span>
  </div>

  <div class="svg-container">
    <svg viewBox="0 0 600 420" xmlns="http://www.w3.org/2000/svg">
      <defs>
        
        <linearGradient id="flaskSolution" x1="0%" y1="0%" x2="0%" y2="100%">
          <stop offset="0%" stop-color="#38bdf8" stop-opacity="0.8"/>
          <stop offset="100%" stop-color="#1d4ed8" stop-opacity="0.9"/>
        </linearGradient>

        <linearGradient id="distillateLiquid" x1="0%" y1="0%" x2="0%" y2="100%">
          <stop offset="0%" stop-color="#bae6fd" stop-opacity="0.6"/>
          <stop offset="100%" stop-color="#7dd3fc" stop-opacity="0.9"/>
        </linearGradient>

        <linearGradient id="waterJacketGrad" x1="0%" y1="0%" x2="100%" y2="100%">
          <stop offset="0%" stop-color="#e0f2fe" stop-opacity="0.6"/>
          <stop offset="100%" stop-color="#bae6fd" stop-opacity="0.8"/>
        </linearGradient>

        <linearGradient id="flameGrad" x1="0%" y1="100%" x2="0%" y2="0%">
          <stop offset="0%" stop-color="#ef4444"/>
          <stop offset="50%" stop-color="#f59e0b"/>
          <stop offset="100%" stop-color="#38bdf8"/>
        </linearGradient>

        <filter id="glow" x="-20%" y="-20%" width="140%" height="140%">
          <feGaussianBlur stdDeviation="3" result="glow"/>
          <feComposite in="SourceGraphic" in2="glow" operator="over"/>
        </filter>
      </defs>

      
      <g stroke="#94a3b8" stroke-width="4" stroke-linecap="round">
        
        <line x1="50" y1="390" x2="120" y2="390"/>
        <line x1="85" y1="390" x2="85" y2="100"/>
        <line x1="85" y1="170" x2="135" y2="170" stroke-width="3"/>
        <circle cx="85" cy="170" r="4" fill="#64748b"/>

        
        <line x1="360" y1="390" x2="430" y2="390"/>
        <line x1="395" y1="390" x2="395" y2="160"/>
        <line x1="395" y1="210" x2="355" y2="225" stroke-width="3"/>
        <circle cx="395" cy="210" r="4" fill="#64748b"/>
      </g>

      
      <g stroke="#64748b" stroke-width="3">
        <line x1="100" y1="330" x2="170" y2="330"/>
        <line x1="95" y1="330" x2="80" y2="390"/>
        <line x1="175" y1="330" x2="190" y2="390"/>
        <line x1="135" y1="330" x2="135" y2="390" stroke-width="2"/>
        
        <rect x="110" y="327" width="50" height="3" fill="#cbd5e1" stroke="none"/>
      </g>

      
      <g id="part-heat">
        
        <path d="M120,390 L150,390 L145,384 L138,384 L138,350 L132,350 L132,384 L125,384 Z" fill="#475569"/>
        <rect x="130" y="375" width="10" height="4" fill="#334155"/>
        
        <path d="M135,348 Q127,330 135,308 Q143,330 135,348 Z" fill="url(#flameGrad)" opacity="0.9" filter="url(#glow)"/>
        
        <path d="M135,348 Q131,336 135,322 Q139,336 135,348 Z" fill="#67e8f9"/>
      </g>

      
      <g id="part-flask">
        
        <path d="M102,280 C102,315 120,326 135,326 C150,326 168,315 168,280 C155,278 115,278 102,280 Z" fill="url(#flaskSolution)"/>

        
        <g id="part-granules" fill="#475569">
          <circle cx="120" cy="320" r="3"/>
          <circle cx="130" cy="323" r="2.5"/>
          <circle cx="138" cy="321" r="3.2"/>
          <circle cx="148" cy="319" r="2.7"/>
          <circle cx="127" cy="316" r="2.2"/>
        </g>

        
        <g fill="#38bdf8" opacity="0.7">
          <circle cx="125" cy="270" r="2.5" class="vapor-bubble" style="animation-delay: 0s;"/>
          <circle cx="140" cy="265" r="2" class="vapor-bubble" style="animation-delay: 0.8s;"/>
          <circle cx="133" cy="255" r="3" class="vapor-bubble" style="animation-delay: 1.6s;"/>
        </g>

        
        
        <path d="M125,120 L125,205 C100,225 98,275 102,295 C108,320 125,328 135,328 C145,328 162,320 168,295 C172,275 170,225 145,205 L145,160 L200,192 L196,199 L145,169 L145,120 Z" 
              fill="none" stroke="#334155" stroke-width="2.5" stroke-linejoin="round"/>
        
        <polygon points="123,120 147,120 144,102 126,102" fill="#64748b"/>
      </g>

      
      <g id="part-thermometer">
        
        <rect x="133.5" y="60" width="3" height="106" fill="#e2e8f0" stroke="#475569" stroke-width="1"/>
        
        <line x1="135" y1="165" x2="135" y2="85" stroke="#ef4444" stroke-width="1.6"/>
        
        <circle cx="135" cy="164.5" r="3.8" fill="#ef4444"/>
        
        
        <line x1="135" y1="164.5" x2="198" y2="164.5" stroke="#0284c7" stroke-width="1" stroke-dasharray="2,2" opacity="0.6"/>
      </g>

      
      
      <g id="part-condenser">
        
        <g transform="rotate(30, 200, 196)">
          
          <rect x="230" y="180" width="180" height="32" rx="4" fill="url(#waterJacketGrad)" stroke="#334155" stroke-width="2"/>
          
          
          <rect x="195" y="191" width="250" height="10" fill="#ffffff" fill-opacity="0.4" stroke="#334155" stroke-width="1.8"/>

          
          <path d="M250,180 L250,162 L260,162 L260,180" fill="#e0f2fe" stroke="#334155" stroke-width="1.8"/>
          
          <path d="M380,212 L380,230 L390,230 L390,212" fill="#e0f2fe" stroke="#334155" stroke-width="1.8"/>

          
          <line x1="200" y1="196" x2="435" y2="196" stroke="#0284c7" stroke-width="2.5" class="vapor-stream" opacity="0.8"/>
        </g>

        
        <g id="part-water">
          
          <path d="M245,150 L245,132" stroke="#0284c7" stroke-width="2.5" stroke-linecap="round" marker-end="none"/>
          <polygon points="241,135 245,127 249,135" fill="#0284c7"/>
          <text x="245" y="120" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Water Out</text>
          <text x="245" y="108" font-size="9.5" fill="#64748b" text-anchor="middle">(Warm)</text>

          
          <path d="M410,345 L410,323" stroke="#0284c7" stroke-width="2.5" stroke-linecap="round"/>
          <polygon points="406,327 410,319 414,327" fill="#0284c7"/>
          <text x="410" y="362" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Water In</text>
          <text x="410" y="374" font-size="9.5" fill="#64748b" text-anchor="middle">(Cold)</text>
        </g>
      </g>

      
      <g id="part-receiver">
        
        <path d="M416,321 L435,332 L435,348" fill="none" stroke="#334155" stroke-width="2"/>
        
        
        <circle cx="435" cy="350" r="2.5" fill="#0284c7" class="drop"/>

        
        <polygon points="425,345 445,345 465,395 405,395" fill="#f8fafc" stroke="#334155" stroke-width="2" stroke-linejoin="round"/>
        
        <polygon points="413,375 457,375 463,393 407,393" fill="url(#distillateLiquid)"/>
      </g>

      
      <rect id="hl-thermometer" class="part-highlight" x="115" y="55" width="40" height="120" rx="8" fill="#38bdf8" fill-opacity="0.2" stroke="#0284c7" stroke-width="2"/>
      <circle id="hl-flask" class="part-highlight" cx="135" cy="270" r="48" fill="#38bdf8" fill-opacity="0.15" stroke="#0284c7" stroke-width="2"/>
      <ellipse id="hl-condenser" class="part-highlight" cx="308" cy="258" rx="115" ry="34" transform="rotate(30, 308, 258)" fill="#38bdf8" fill-opacity="0.15" stroke="#0284c7" stroke-width="2"/>
      <circle id="hl-receiver" class="part-highlight" cx="435" cy="370" r="36" fill="#38bdf8" fill-opacity="0.15" stroke="#0284c7" stroke-width="2"/>
      <rect id="hl-heat" class="part-highlight" x="110" y="305" width="50" height="90" rx="6" fill="#f59e0b" fill-opacity="0.15" stroke="#f59e0b" stroke-width="2"/>
      <circle id="hl-granules" class="part-highlight" cx="135" cy="320" r="22" fill="#64748b" fill-opacity="0.2" stroke="#475569" stroke-width="1.5"/>

      
      
      <g class="hotspot" data-target="thermometer" transform="translate(135, 140)">
        <circle class="hotspot-pulse" r="10" fill="#0284c7"/>
        <circle class="hotspot-circle" r="8" fill="#0ea5e9" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">1</text>
      </g>

      
      <g class="hotspot" data-target="flask" transform="translate(100, 240)">
        <circle class="hotspot-pulse" r="10" fill="#0284c7"/>
        <circle class="hotspot-circle" r="8" fill="#0ea5e9" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">2</text>
      </g>

      
      <g class="hotspot" data-target="granules" transform="translate(162, 320)">
        <circle class="hotspot-pulse" r="10" fill="#0284c7"/>
        <circle class="hotspot-circle" r="8" fill="#0ea5e9" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">3</text>
      </g>

      
      <g class="hotspot" data-target="heat" transform="translate(170, 365)">
        <circle class="hotspot-pulse" r="10" fill="#f59e0b"/>
        <circle class="hotspot-circle" r="8" fill="#f59e0b" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">4</text>
      </g>

      
      <g class="hotspot" data-target="condenser" transform="translate(315, 235)">
        <circle class="hotspot-pulse" r="10" fill="#0284c7"/>
        <circle class="hotspot-circle" r="8" fill="#0ea5e9" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">5</text>
      </g>

      
      <g class="hotspot" data-target="water" transform="translate(340, 310)">
        <circle class="hotspot-pulse" r="10" fill="#0284c7"/>
        <circle class="hotspot-circle" r="8" fill="#0ea5e9" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">6</text>
      </g>

      
      <g class="hotspot" data-target="receiver" transform="translate(470, 370)">
        <circle class="hotspot-pulse" r="10" fill="#0284c7"/>
        <circle class="hotspot-circle" r="8" fill="#0ea5e9" stroke="#ffffff" stroke-width="1.5"/>
        <text y="3.5" font-size="9" font-weight="bold" fill="#ffffff" text-anchor="middle">7</text>
      </g>
    </svg>
  </div>

  
  <div class="info-card" id="infoCard">
    <span class="info-badge" id="infoBadge">Overview</span>
    <span class="info-text" id="infoText">Tap numbered markers to explore each component of the simple distillation apparatus.</span>
  </div>

  <script>
    const data = {
      thermometer: {
        title: "Thermometer",
        text: "Bulb aligns with side-arm to measure true boiling point of vapor entering condenser."
      },
      flask: {
        title: "Distillation Flask",
        text: "Holds solution. Liquid with lower boiling point vaporizes first and leaves non-volatile solutes behind."
      },
      granules: {
        title: "Anti-Bumping Granules",
        text: "Rough porcelain chips provide nucleation sites for small bubbles, preventing violent boiling."
      },
      heat: {
        title: "Bunsen Burner",
        text: "Supplies thermal energy to boil the solution and maintain vapor flow."
      },
      condenser: {
        title: "Liebig Condenser",
        text: "Slopes downward. Outer cold jacket chills vapor inside inner tube, condensing it to liquid."
      },
      water: {
        title: "Water In / Water Out",
        text: "Cold water enters at bottom and exits at top to fill jacket completely without air pockets."
      },
      receiver: {
        title: "Receiving Flask",
        text: "Collects pure condensed liquid (distillate) separate from the original mixture."
      }
    };

    const hotspots = document.querySelectorAll('.hotspot');
    const highlights = document.querySelectorAll('.part-highlight');
    const infoBadge = document.getElementById('infoBadge');
    const infoText = document.getElementById('infoText');

    function selectPart(key) {
      // Update highlights
      highlights.forEach(hl => hl.classList.remove('active'));
      const activeHl = document.getElementById('hl-' + key);
      if (activeHl) activeHl.classList.add('active');

      // Update hotspot active state
      hotspots.forEach(hs => {
        if (hs.getAttribute('data-target') === key) {
          hs.classList.add('active');
        } else {
          hs.classList.remove('active');
        }
      });

      // Update text
      if (data[key]) {
        infoBadge.textContent = data[key].title;
        infoText.textContent = data[key].text;
      }
    }

    hotspots.forEach(hs => {
      hs.addEventListener('click', (e) => {
        e.stopPropagation();
        const target = hs.getAttribute('data-target');
        selectPart(target);
      });
    });

    document.body.addEventListener('click', (e) => {
      if (!e.target.closest('.hotspot')) {
        highlights.forEach(hl => hl.classList.remove('active'));
        hotspots.forEach(hs => hs.classList.remove('active'));
        infoBadge.textContent = "Overview";
        infoText.textContent = "Tap numbered markers to explore each component of the simple distillation apparatus.";
      }
    });
  </script>
</body>
</html>

Simple Distillation: Principles and Apparatus

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Liebig Condenser - Counter-Current Cooling</title>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: transparent;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 8px 4px;
      user-select: none;
      width: 100%;
      min-height: 100vh;
      overflow-x: hidden;
    }

    /* Controls */
    .controls {
      display: flex;
      gap: 10px;
      margin-bottom: 8px;
      width: 100%;
      max-width: 580px;
      justify-content: center;
    }
    .toggle-btn {
      flex: 1;
      min-height: 44px;
      padding: 8px 14px;
      font-size: 15px;
      font-weight: 600;
      border-radius: 8px;
      border: 2px solid #cbd5e1;
      background: #f8fafc;
      color: #475569;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
    }
    .toggle-btn:focus-visible {
      outline: 2px solid #2563eb;
      outline-offset: 2px;
    }
    .toggle-btn.active.correct {
      background: #f0fdf4;
      border-color: #16a34a;
      color: #15803d;
    }
    .toggle-btn.active.incorrect {
      background: #fef2f2;
      border-color: #dc2626;
      color: #b91c1c;
    }

    /* SVG container - flat, no card frame */
    .diagram-area {
      width: 100%;
      max-width: 600px;
      background: transparent;
      position: relative;
    }
    svg {
      display: block;
      width: 100%;
      height: auto;
      overflow: visible;
    }

    /* Calmed, accessible animation speeds */
    .flow-line {
      stroke-dasharray: 8 6;
      animation: flowReverse 3.5s linear infinite;
    }
    .flow-line-incorrect {
      stroke-dasharray: 8 6;
      animation: flowForward 3.5s linear infinite;
    }
    @keyframes flowReverse {
      from { stroke-dashoffset: 28; }
      to { stroke-dashoffset: 0; }
    }
    @keyframes flowForward {
      from { stroke-dashoffset: 0; }
      to { stroke-dashoffset: 28; }
    }

    .vapor-particle {
      animation: moveVapor 4.8s ease-in-out infinite;
    }
    @keyframes moveVapor {
      0% { transform: translate(0, 0); opacity: 0; }
      15% { opacity: 0.85; }
      70% { opacity: 0.85; }
      100% { transform: translate(320px, 110px); opacity: 0; }
    }

    .drop-particle {
      animation: dropFall 2.4s cubic-bezier(0.4, 0, 0.6, 1) infinite;
    }
    @keyframes dropFall {
      0% { transform: translate(0, 0); opacity: 0; }
      20% { opacity: 1; }
      80% { opacity: 1; }
      100% { transform: translate(0, 36px); opacity: 0; }
    }

    @media (max-width: 480px) {
      .controls {
        flex-direction: column;
      }
      .toggle-btn {
        width: 100%;
        font-size: 14px;
        min-height: 40px;
      }
    }
  </style>
</head>
<body>

  <div class="controls" role="tablist" aria-label="Condenser flow configuration">
    <button class="toggle-btn active correct" id="btnCorrect" role="tab" aria-selected="true">
      <span aria-hidden="true">✓</span> Correct Flow (Bottom In)
    </button>
    <button class="toggle-btn" id="btnIncorrect" role="tab" aria-selected="false">
      <span aria-hidden="true">✕</span> Incorrect Flow (Top In)
    </button>
  </div>

  <div class="diagram-area">
    <svg viewBox="0 0 600 350" aria-label="Liebig condenser apparatus diagram">
      <defs>
        
        <linearGradient id="correctWater" x1="1" y1="1" x2="0" y2="0">
          <stop offset="0%" stop-color="#38bdf8" stop-opacity="0.85"/>
          <stop offset="100%" stop-color="#fdba74" stop-opacity="0.65"/>
        </linearGradient>

        <linearGradient id="incorrectWater" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#38bdf8" stop-opacity="0.85"/>
          <stop offset="100%" stop-color="#60a5fa" stop-opacity="0.85"/>
        </linearGradient>

        <linearGradient id="innerCondense" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#fda4af" stop-opacity="0.45"/>
          <stop offset="45%" stop-color="#93c5fd" stop-opacity="0.45"/>
          <stop offset="100%" stop-color="#38bdf8" stop-opacity="0.75"/>
        </linearGradient>

        <marker id="arrowRed" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
          <path d="M 0 1 L 8 5 L 0 9 z" fill="#be123c"/>
        </marker>
      </defs>

      
      <g stroke="#f1f5f9" stroke-width="1.5" aria-hidden="true">
        <line x1="10" y1="90" x2="590" y2="90" />
        <line x1="10" y1="175" x2="590" y2="175" />
        <line x1="10" y1="260" x2="590" y2="260" />
      </g>

      
      
      <g id="jacketFull">
        
        <polygon points="175,90 425,178 410,220 160,132" fill="url(#correctWater)" />
        
        <rect x="180" y="50" width="22" height="52" fill="#fdba74" fill-opacity="0.65" />
        
        <rect x="382" y="196" width="22" height="56" fill="#38bdf8" fill-opacity="0.85" />
      </g>

      
      <g id="jacketPartial" style="display: none;">
        
        <polygon points="175,90 425,178 417,200 167,112" fill="#e2e8f0" fill-opacity="0.5" stroke="#94a3b8" stroke-dasharray="4 4" stroke-width="1.5" />
        
        <polygon points="167,112 417,200 410,220 160,132" fill="url(#incorrectWater)" />
        
        <rect x="180" y="50" width="22" height="52" fill="#38bdf8" fill-opacity="0.85" />
        
        <rect x="382" y="196" width="22" height="56" fill="#60a5fa" fill-opacity="0.85" />
        
        <g transform="translate(292, 126)">
          <rect x="-56" y="-14" width="112" height="28" rx="6" fill="#ffffff" fill-opacity="0.95" stroke="#64748b" stroke-width="1.5"/>
          <text x="0" y="5" text-anchor="middle" font-size="15" font-weight="700" fill="#475569">Air Pocket ⚠️</text>
        </g>
      </g>

      
      
      <g stroke="#475569" stroke-width="2.5" fill="none">
        
        <line x1="180" y1="50" x2="180" y2="92" />
        <line x1="202" y1="50" x2="202" y2="100" />
        <ellipse cx="191" cy="50" rx="11" ry="3.5" fill="#f8fafc" stroke="#475569" stroke-width="2" />

        
        <line x1="382" y1="210" x2="382" y2="252" />
        <line x1="404" y1="218" x2="404" y2="252" />
        <ellipse cx="393" cy="252" rx="11" ry="3.5" fill="#f8fafc" stroke="#475569" stroke-width="2" />

        
        <line x1="175" y1="90" x2="425" y2="178" />
        <line x1="160" y1="132" x2="410" y2="220" />
        
        <line x1="175" y1="90" x2="160" y2="132" />
        <line x1="425" y1="178" x2="410" y2="220" />
      </g>

      
      <g>
        
        <polygon points="90,75 480,212 473,234 83,97" fill="url(#innerCondense)" />

        
        <line x1="75" y1="70" x2="495" y2="217" stroke="#334155" stroke-width="2" />
        <line x1="68" y1="92" x2="488" y2="239" stroke="#334155" stroke-width="2" />

        
        <g id="correctCondensate">
          <ellipse cx="270" cy="155" rx="5" ry="3" fill="#0284c7" opacity="0.7"/>
          <ellipse cx="340" cy="183" rx="7" ry="4" fill="#0284c7" opacity="0.85"/>
          <ellipse cx="410" cy="210" rx="9" ry="5.5" fill="#0284c7" opacity="0.95"/>
          <ellipse cx="475" cy="232" rx="11" ry="6" fill="#0284c7" />
          
          
          <path d="M485,236 Q495,240 500,260" fill="none" stroke="#0284c7" stroke-width="4" stroke-linecap="round"/>
          <circle cx="500" cy="275" r="5" fill="#0284c7" class="drop-particle" />
        </g>

        
        <g id="incorrectCondensate" style="display:none;">
          <ellipse cx="340" cy="187" rx="4" ry="2.5" fill="#0284c7" opacity="0.5"/>
          <ellipse cx="440" cy="222" rx="6" ry="3.5" fill="#0284c7" opacity="0.7"/>
          
          <path d="M490,215 Q515,205 525,185" fill="none" stroke="#e11d48" stroke-width="3" stroke-dasharray="4 3" opacity="0.9" />
          <path d="M495,225 Q525,220 540,205" fill="none" stroke="#e11d48" stroke-width="3" stroke-dasharray="4 3" opacity="0.9" />
          
          <circle cx="498" cy="265" r="3.5" fill="#0284c7" opacity="0.6" class="drop-particle" />
        </g>
      </g>

      
      <g>
        <circle cx="100" cy="85" r="5" fill="#e11d48" opacity="0.85" class="vapor-particle" style="animation-delay: 0s;" />
        <circle cx="100" cy="85" r="4.5" fill="#ea580c" opacity="0.85" class="vapor-particle" style="animation-delay: 1.2s;" />
        <circle cx="100" cy="85" r="4" fill="#38bdf8" opacity="0.85" class="vapor-particle" style="animation-delay: 2.4s;" />
        <circle cx="100" cy="85" r="5" fill="#0284c7" opacity="0.85" class="vapor-particle" style="animation-delay: 3.6s;" />
      </g>

      
      
      <g id="flowCorrect">
        
        <path d="M393,285 L393,215" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" class="flow-line" />
        <polygon points="393,205 387,218 399,218" fill="#0284c7" />

        
        <path d="M370,195 L220,142" fill="none" stroke="#0284c7" stroke-width="2.5" stroke-linecap="round" class="flow-line" opacity="0.7"/>
        <path d="M360,165 L210,112" fill="none" stroke="#c2410c" stroke-width="2.5" stroke-linecap="round" class="flow-line" opacity="0.7"/>

        
        <path d="M191,85 L191,25" fill="none" stroke="#c2410c" stroke-width="3" stroke-linecap="round" class="flow-line" />
        <polygon points="191,15 185,28 197,28" fill="#c2410c" />
      </g>

      
      <g id="flowIncorrect" style="display: none;">
        
        <path d="M191,20 L191,80" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" class="flow-line-incorrect" />
        <polygon points="191,88 185,75 197,75" fill="#0284c7" />

        
        <path d="M185,124 L380,193" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" class="flow-line-incorrect" />

        
        <path d="M393,220 L393,285" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round" class="flow-line-incorrect" />
        <polygon points="393,293 387,280 399,280" fill="#0284c7" />
      </g>

      
      
      <g transform="translate(70, 42)">
        <text x="0" y="0" text-anchor="middle" font-size="16" font-weight="700" fill="#be123c">Vapour In</text>
        <path d="M0,6 L20,24" stroke="#be123c" stroke-width="2" marker-end="url(#arrowRed)" fill="none" />
      </g>

      
      <g id="lblDistillate" transform="translate(505, 318)">
        <text x="0" y="0" text-anchor="middle" font-size="16" font-weight="700" fill="#0369a1">Distillate</text>
      </g>
      <g id="lblVaporEscape" transform="translate(530, 160)" style="display:none;">
        <text x="0" y="0" text-anchor="middle" font-size="15" font-weight="700" fill="#be123c">Vapour lost! ⚠️</text>
      </g>

      
      
      <g id="lblTopPort" transform="translate(191, 14)">
        <text x="0" y="0" text-anchor="middle" font-size="16" font-weight="700" fill="#c2410c">Warm Water Out</text>
      </g>

      
      <g id="lblBottomPort" transform="translate(393, 318)">
        <text x="0" y="0" text-anchor="middle" font-size="16" font-weight="700" fill="#0369a1">Cold Water In</text>
      </g>
    </svg>
  </div>

  <script>
    const btnCorrect = document.getElementById('btnCorrect');
    const btnIncorrect = document.getElementById('btnIncorrect');

    const jacketFull = document.getElementById('jacketFull');
    const jacketPartial = document.getElementById('jacketPartial');
    const flowCorrect = document.getElementById('flowCorrect');
    const flowIncorrect = document.getElementById('flowIncorrect');
    const correctCondensate = document.getElementById('correctCondensate');
    const incorrectCondensate = document.getElementById('incorrectCondensate');

    const lblTopPort = document.getElementById('lblTopPort').querySelector('text');
    const lblBottomPort = document.getElementById('lblBottomPort').querySelector('text');
    const lblVaporEscape = document.getElementById('lblVaporEscape');

    function setMode(isCorrect) {
      if (isCorrect) {
        btnCorrect.className = 'toggle-btn active correct';
        btnCorrect.setAttribute('aria-selected', 'true');
        btnIncorrect.className = 'toggle-btn';
        btnIncorrect.setAttribute('aria-selected', 'false');

        jacketFull.style.display = 'block';
        jacketPartial.style.display = 'none';

        flowCorrect.style.display = 'block';
        flowIncorrect.style.display = 'none';

        correctCondensate.style.display = 'block';
        incorrectCondensate.style.display = 'none';
        lblVaporEscape.style.display = 'none';

        lblTopPort.textContent = 'Warm Water Out';
        lblTopPort.setAttribute('fill', '#c2410c');

        lblBottomPort.textContent = 'Cold Water In';
        lblBottomPort.setAttribute('fill', '#0369a1');
      } else {
        btnCorrect.className = 'toggle-btn';
        btnCorrect.setAttribute('aria-selected', 'false');
        btnIncorrect.className = 'toggle-btn active incorrect';
        btnIncorrect.setAttribute('aria-selected', 'true');

        jacketFull.style.display = 'none';
        jacketPartial.style.display = 'block';

        flowCorrect.style.display = 'none';
        flowIncorrect.style.display = 'block';

        correctCondensate.style.display = 'none';
        incorrectCondensate.style.display = 'block';
        lblVaporEscape.style.display = 'block';

        lblTopPort.textContent = 'Water In (Top)';
        lblTopPort.setAttribute('fill', '#0369a1');

        lblBottomPort.textContent = 'Water Out (Drains)';
        lblBottomPort.setAttribute('fill', '#475569');
      }
    }

    btnCorrect.addEventListener('click', () => setMode(true));
    btnIncorrect.addEventListener('click', () => setMode(false));
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: #ffffff;
      padding: 10px;
      user-select: none;
      -webkit-user-select: none;
    }
    
    .nav-bar {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 6px;
      margin-bottom: 8px;
    }
    .step-tabs {
      display: flex;
      gap: 4px;
      flex: 1;
    }
    .step-btn {
      flex: 1;
      padding: 6px 4px;
      font-size: 13px;
      font-weight: 600;
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      color: #475569;
      cursor: pointer;
      text-align: center;
      transition: background 0.2s, color 0.2s, border-color 0.2s;
      white-space: nowrap;
    }
    .step-btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #1d4ed8;
    }
    .play-btn {
      padding: 6px 12px;
      font-size: 13px;
      font-weight: 600;
      background: #f8fafc;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      color: #1e2945;
      cursor: pointer;
    }

    .canvas-container {
      position: relative;
      width: 100%;
      height: 380px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      overflow: hidden;
    }

    svg {
      width: 100%;
      height: 100%;
      display: block;
    }

    /* SVG Animations */
    .steam-bubble {
      animation: riseUp 1.8s infinite linear;
    }
    @keyframes riseUp {
      0% { transform: translateY(0); opacity: 0; }
      50% { opacity: 0.8; }
      100% { transform: translateY(-35px); opacity: 0; }
    }

    .drop {
      animation: drip 1.2s infinite ease-in;
    }
    @keyframes drip {
      0% { transform: translateY(0); opacity: 0; }
      30% { opacity: 1; }
      90% { transform: translateY(32px); opacity: 1; }
      100% { transform: translateY(34px); opacity: 0; }
    }

    .flame-flicker {
      animation: flicker 0.4s infinite alternate ease-in-out;
      transform-origin: 105px 335px;
    }
    @keyframes flicker {
      0% { transform: scaleY(0.92) scaleX(0.96); }
      100% { transform: scaleY(1.08) scaleX(1.04); }
    }

    /* Badges */
    .status-badge {
      position: absolute;
      top: 10px;
      right: 10px;
      background: rgba(255, 255, 255, 0.95);
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 6px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #0f172a;
      box-shadow: 0 1px 4px rgba(0,0,0,0.06);
    }
    .badge-hl {
      color: #2563eb;
    }
  </style>
</head>
<body>

  <div class="nav-bar">
    <div class="step-tabs">
      <button class="step-btn active" id="btn-0" onclick="setStep(0)">1. Mixture</button>
      <button class="step-btn" id="btn-1" onclick="setStep(1)">2. Boiling &amp; Cooling</button>
      <button class="step-btn" id="btn-2" onclick="setStep(2)">3. Separated</button>
    </div>
    <button class="play-btn" id="playBtn" onclick="togglePlay()">⏸</button>
  </div>

  <div class="canvas-container">
    <div class="status-badge" id="statusBadge">
      Flask: <span class="badge-hl">Dilute CuSO₄(aq)</span>
    </div>

    <svg viewBox="0 0 540 380">
      <defs>
        
        <linearGradient id="flaskSolution1" x1="0" y1="0" x2="0" y2="1">
          <stop offset="0%" stop-color="#60a5fa" stop-opacity="0.8"/>
          <stop offset="100%" stop-color="#3b82f6" stop-opacity="0.95"/>
        </linearGradient>
        <linearGradient id="flaskSolution2" x1="0" y1="0" x2="0" y2="1">
          <stop offset="0%" stop-color="#2563eb" stop-opacity="0.9"/>
          <stop offset="100%" stop-color="#1e40af" stop-opacity="1"/>
        </linearGradient>
        <linearGradient id="waterGrad" x1="0" y1="0" x2="0" y2="1">
          <stop offset="0%" stop-color="#bae6fd" stop-opacity="0.6"/>
          <stop offset="100%" stop-color="#7dd3fc" stop-opacity="0.85"/>
        </linearGradient>
        <linearGradient id="jacketGrad" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#0284c7" stop-opacity="0.18"/>
          <stop offset="100%" stop-color="#38bdf8" stop-opacity="0.28"/>
        </linearGradient>
        <linearGradient id="flameGrad" x1="0" y1="1" x2="0" y2="0">
          <stop offset="0%" stop-color="#f97316"/>
          <stop offset="60%" stop-color="#fbbf24"/>
          <stop offset="100%" stop-color="#60a5fa"/>
        </linearGradient>
      </defs>

      
      
      <line x1="60" y1="340" x2="90" y2="245" stroke="#64748b" stroke-width="3.5" stroke-linecap="round"/>
      <line x1="150" y1="340" x2="120" y2="245" stroke="#64748b" stroke-width="3.5" stroke-linecap="round"/>
      <line x1="105" y1="340" x2="105" y2="245" stroke="#94a3b8" stroke-width="2.5" stroke-linecap="round"/>
      <line x1="75" y1="245" x2="135" y2="245" stroke="#334155" stroke-width="4" stroke-linecap="round"/>
      
      <line x1="80" y1="243" x2="130" y2="243" stroke="#94a3b8" stroke-width="2" stroke-dasharray="2,2"/>

      
      <rect x="98" y="295" width="14" height="45" fill="#64748b" rx="2"/>
      <rect x="85" y="340" width="40" height="7" fill="#334155" rx="2"/>
      
      <g id="flameGroup" class="flame-flicker">
        <path d="M 100 295 Q 105 255 105 255 Q 105 255 110 295 Z" fill="url(#flameGrad)"/>
      </g>

      
      <rect x="420" y="340" width="80" height="7" fill="#cbd5e1" rx="2"/>

      
      
      
      
      <g id="flaskContents">
        
        <g id="sol-step-0">
          <path d="M 67 215 C 67 236 84 240 105 240 C 126 240 143 236 143 215 C 137 205 73 205 67 215 Z" fill="url(#flaskSolution1)"/>
          <ellipse cx="105" cy="207" rx="36" ry="7" fill="#93c5fd" opacity="0.6"/>
          
          <circle cx="95" cy="235" r="2.5" fill="#475569"/>
          <circle cx="108" cy="237" r="3" fill="#475569"/>
          <circle cx="118" cy="234" r="2.5" fill="#475569"/>
        </g>
        
        
        <g id="sol-step-1" style="display:none;">
          <path d="M 75 227 C 78 238 90 240 105 240 C 120 240 132 238 135 227 C 130 222 80 222 75 227 Z" fill="url(#flaskSolution2)"/>
          <ellipse cx="105" cy="223" rx="28" ry="5" fill="#3b82f6" opacity="0.8"/>
          
          <circle cx="95" cy="235" r="2.5" fill="#475569"/>
          <circle cx="108" cy="237" r="3" fill="#475569"/>
          <circle cx="118" cy="234" r="2.5" fill="#475569"/>
          
          <g class="steam-bubble">
            <circle cx="98" cy="210" r="3" fill="#ffffff" opacity="0.7"/>
            <circle cx="112" cy="205" r="4" fill="#ffffff" opacity="0.7"/>
            <circle cx="104" cy="190" r="3.5" fill="#ffffff" opacity="0.7"/>
          </g>
        </g>

        
        <g id="sol-step-2" style="display:none;">
          <path d="M 85 237 Q 105 235 125 237 Q 105 242 85 237 Z" fill="#1e40af"/>
          <circle cx="92" cy="237" r="2.5" fill="#93c5fd"/>
          <circle cx="102" cy="236" r="3" fill="#1d4ed8"/>
          <circle cx="112" cy="237" r="2.5" fill="#60a5fa"/>
          <circle cx="118" cy="236" r="3" fill="#93c5fd"/>
          <circle cx="95" cy="235" r="2.5" fill="#475569"/>
          <circle cx="108" cy="237" r="3" fill="#475569"/>
          <text x="105" y="218" text-anchor="middle" font-size="11" font-weight="700" fill="#1e3a8a">CuSO₄ solid</text>
        </g>
      </g>

      
      <path d="M 98 120 L 98 165 C 73 175 60 205 65 225 C 72 250 138 250 145 225 C 150 205 137 175 112 165 L 112 120" 
            fill="none" stroke="#64748b" stroke-width="2.5" stroke-linejoin="round"/>

      
      <rect x="96" y="112" width="18" height="10" fill="#94a3b8" rx="2"/>

      
      <rect x="103" y="60" width="4" height="95" fill="#e2e8f0" stroke="#94a3b8" stroke-width="1"/>
      <line id="thermoLiquid" x1="105" y1="150" x2="105" y2="90" stroke="#ef4444" stroke-width="2.5"/>
      <circle cx="105" cy="152" r="3.5" fill="#ef4444"/>
      
      
      <g id="tempBadge">
        <rect x="32" y="68" width="62" height="22" fill="#ffffff" stroke="#ef4444" stroke-width="1.5" rx="4"/>
        <text id="tempText" x="63" y="83" font-size="12" font-weight="700" fill="#dc2626" text-anchor="middle">100°C</text>
        <line x1="94" y1="79" x2="103" y2="79" stroke="#ef4444" stroke-width="1.5"/>
      </g>

      
      
      <g id="condenserGroup">
        
        <line x1="112" y1="140" x2="390" y2="280" stroke="#64748b" stroke-width="4"/>
        <line x1="112" y1="140" x2="390" y2="280" stroke="#ffffff" stroke-width="2"/>

        
        <line x1="160" y1="164" x2="345" y2="257" stroke="url(#jacketGrad)" stroke-width="24" stroke-linecap="round"/>
        <line x1="160" y1="164" x2="345" y2="257" stroke="#38bdf8" stroke-width="24" stroke-linecap="round" opacity="0.3"/>
        <line x1="160" y1="164" x2="345" y2="257" stroke="#0284c7" stroke-width="1.5" stroke-linecap="round" fill="none"/>

        
        <line x1="330" y1="262" x2="330" y2="285" stroke="#0284c7" stroke-width="5" stroke-linecap="round"/>
        <path d="M 330 300 L 330 285" stroke="#0284c7" stroke-width="2" marker-end="url(#arrow)"/>
        <text x="330" y="315" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Water in (cold)</text>
        <path d="M 330 298 L 330 287" stroke="#0284c7" stroke-width="2"/>
        <polygon points="327,288 333,288 330,282" fill="#0284c7"/>

        
        <line x1="175" y1="160" x2="175" y2="135" stroke="#0284c7" stroke-width="5" stroke-linecap="round"/>
        <text x="175" y="118" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Water out (warm)</text>
        <line x1="175" y1="133" x2="175" y2="123" stroke="#0284c7" stroke-width="2"/>
        <polygon points="172,125 178,125 175,119" fill="#0284c7"/>

        
        <g id="condenserDrops" style="display:none;">
          <circle cx="210" cy="190" r="2.5" fill="#38bdf8"/>
          <circle cx="250" cy="210" r="3" fill="#0284c7"/>
          <circle cx="290" cy="230" r="3.5" fill="#0284c7"/>
          <circle cx="330" cy="250" r="3.5" fill="#0284c7"/>
        </g>
      </g>

      
      
      <path d="M 388 279 L 410 290 L 410 305" fill="none" stroke="#64748b" stroke-width="3" stroke-linecap="round"/>
      
      
      <g id="drippingWater" style="display:none;">
        <g class="drop">
          <circle cx="410" cy="308" r="2.5" fill="#38bdf8"/>
        </g>
      </g>

      
      
      <g id="receiverContents">
        
        
        <g id="rec-step-1" style="display:none;">
          <polygon points="432,335 488,335 480,315 440,315" fill="url(#waterGrad)"/>
          <ellipse cx="460" cy="315" rx="20" ry="3.5" fill="#e0f2fe"/>
        </g>
        
        <g id="rec-step-2" style="display:none;">
          <polygon points="432,335 488,335 474,290 446,290" fill="url(#waterGrad)"/>
          <ellipse cx="460" cy="290" rx="14" ry="3" fill="#e0f2fe"/>
          <text x="460" y="322" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Pure H₂O</text>
        </g>
      </g>

      
      <path d="M 452 270 L 452 280 L 430 338 C 428 340 430 340 435 340 L 485 340 C 490 340 492 340 490 338 L 468 280 L 468 270 Z" 
            fill="none" stroke="#64748b" stroke-width="2" stroke-linejoin="round"/>

      
      <text x="105" y="42" font-size="12" font-weight="700" fill="#334155" text-anchor="middle">Thermometer</text>
      <text x="260" y="152" font-size="12" font-weight="700" fill="#0369a1" text-anchor="middle">Liebig Condenser</text>
      <text x="460" y="258" font-size="12" font-weight="700" fill="#334155" text-anchor="middle">Distillate</text>
    </svg>
  </div>

  <script>
    let currentStep = 0;
    let timer = null;
    let isPlaying = true;

    const badges = [
      'Flask: <span class="badge-hl">Dilute CuSO₄(aq)</span> (Starting mixture)',
      'Vapor: <span class="badge-hl">100°C Steam</span> cools to Pure Liquid',
      'Result: <span class="badge-hl">Pure Water</span> separated from <span class="badge-hl">Solid CuSO₄</span>'
    ];

    function updateView() {
      // Buttons
      for (let i = 0; i < 3; i++) {
        document.getElementById(`btn-${i}`).classList.toggle('active', i === currentStep);
      }

      // Badge text
      document.getElementById('statusBadge').innerHTML = badges[currentStep];

      // Distilling flask states
      document.getElementById('sol-step-0').style.display = (currentStep === 0) ? 'inline' : 'none';
      document.getElementById('sol-step-1').style.display = (currentStep === 1) ? 'inline' : 'none';
      document.getElementById('sol-step-2').style.display = (currentStep === 2) ? 'inline' : 'none';

      // Flame
      document.getElementById('flameGroup').style.display = (currentStep === 2) ? 'none' : 'inline';

      // Condenser droplets & drip
      document.getElementById('condenserDrops').style.display = (currentStep === 1) ? 'inline' : 'none';
      document.getElementById('drippingWater').style.display = (currentStep === 1) ? 'inline' : 'none';

      // Thermometer reading
      const thermoLiquid = document.getElementById('thermoLiquid');
      const tempText = document.getElementById('tempText');
      if (currentStep === 0) {
        thermoLiquid.setAttribute('y2', '125');
        tempText.textContent = '20°C';
      } else if (currentStep === 1) {
        thermoLiquid.setAttribute('y2', '90');
        tempText.textContent = '100°C';
      } else {
        thermoLiquid.setAttribute('y2', '140');
        tempText.textContent = '25°C';
      }

      // Receiving flask states
      document.getElementById('rec-step-1').style.display = (currentStep === 1) ? 'inline' : 'none';
      document.getElementById('rec-step-2').style.display = (currentStep === 2) ? 'inline' : 'none';
    }

    function setStep(idx) {
      currentStep = idx;
      updateView();
    }

    function nextStep() {
      currentStep = (currentStep + 1) % 3;
      updateView();
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      document.getElementById('playBtn').textContent = isPlaying ? '⏸' : '▶';
      if (isPlaying) {
        startTimer();
      } else {
        clearInterval(timer);
      }
    }

    function startTimer() {
      clearInterval(timer);
      timer = setInterval(nextStep, 3600);
    }

    // Initialize
    updateView();
    startTimer();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: #ffffff;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      user-select: none;
    }

    .header-bar {
      width: 100%;
      max-width: 600px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 8px;
    }

    .legend {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 13px;
      font-weight: 600;
    }

    .legend-item {
      display: flex;
      align-items: center;
      gap: 5px;
    }

    .dot-na {
      width: 14px;
      height: 14px;
      border-radius: 50%;
      background: #10b981;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 10px;
      font-weight: bold;
    }

    .dot-cl {
      width: 16px;
      height: 16px;
      border-radius: 50%;
      background: #f97316;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 10px;
      font-weight: bold;
    }

    .dot-h2o {
      width: 14px;
      height: 14px;
      border-radius: 50%;
      background: #3b82f6;
      display: inline-block;
      position: relative;
    }

    .canvas-container {
      position: relative;
      width: 100%;
      max-width: 600px;
      height: 270px;
      background: #f8fafc;
      border-radius: 12px;
      border: 1px solid #e2e8f0;
      overflow: hidden;
    }

    canvas {
      width: 100%;
      height: 100%;
      display: block;
    }

    .status-badge {
      position: absolute;
      top: 10px;
      right: 10px;
      background: rgba(255, 255, 255, 0.92);
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 4px 8px;
      font-size: 12px;
      font-weight: 600;
      color: #334155;
      pointer-events: none;
    }

    .controls {
      width: 100%;
      max-width: 600px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      margin-top: 10px;
    }

    .slider-row {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .temp-label {
      font-size: 14px;
      font-weight: 700;
      min-width: 65px;
      color: #0f172a;
    }

    input[type="range"] {
      flex: 1;
      -webkit-appearance: none;
      height: 6px;
      border-radius: 3px;
      background: linear-gradient(to right, #38bdf8, #f59e0b, #ef4444);
      outline: none;
      cursor: pointer;
    }

    input[type="range"]::-webkit-slider-thumb {
      -webkit-appearance: none;
      width: 20px;
      height: 20px;
      border-radius: 50%;
      background: #ffffff;
      border: 2px solid #0284c7;
      box-shadow: 0 1px 4px rgba(0,0,0,0.2);
      cursor: pointer;
    }

    .btn-group {
      display: flex;
      gap: 8px;
      justify-content: center;
    }

    .btn {
      flex: 1;
      padding: 7px 12px;
      font-size: 13px;
      font-weight: 600;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      background: #ffffff;
      color: #334155;
      cursor: pointer;
      text-align: center;
      transition: background 0.2s, border-color 0.2s, color 0.2s;
    }

    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }
  </style>
</head>
<body>

  <div class="header-bar">
    <div class="legend">
      <div class="legend-item"><span class="dot-na">+</span> Na⁺</div>
      <div class="legend-item"><span class="dot-cl">−</span> Cl⁻</div>
      <div class="legend-item"><span class="dot-h2o"></span> H₂O</div>
    </div>
  </div>

  <div class="canvas-container">
    <canvas id="simCanvas"></canvas>
    <div id="statusBadge" class="status-badge">Liquid Solution</div>
  </div>

  <div class="controls">
    <div class="slider-row">
      <span id="tempDisplay" class="temp-label">20°C</span>
      <input type="range" id="tempSlider" min="20" max="100" value="20" step="1">
    </div>
    <div class="btn-group">
      <button class="btn active" id="btn20">20°C (Room Temp)</button>
      <button class="btn" id="btn100">100°C (Boiling)</button>
    </div>
  </div>

  <script>
    const canvas = document.getElementById('simCanvas');
    const ctx = canvas.getContext('2d');
    const tempSlider = document.getElementById('tempSlider');
    const tempDisplay = document.getElementById('tempDisplay');
    const statusBadge = document.getElementById('statusBadge');
    const btn20 = document.getElementById('btn20');
    const btn100 = document.getElementById('btn100');

    let width, height;
    let currentTemp = 20;

    function resize() {
      const rect = canvas.getBoundingClientRect();
      width = rect.width;
      height = rect.height;
      canvas.width = width * window.devicePixelRatio;
      canvas.height = height * window.devicePixelRatio;
      ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
    }
    window.addEventListener('resize', resize);
    resize();

    // Lattice target positions for salt ions at dry state
    const cols = 5;
    const rows = 3;
    const latticeSpacing = 22;

    const ions = [];
    let idCounter = 0;
    for (let r = 0; r < rows; r++) {
      for (let c = 0; c < cols; c++) {
        const type = (r + c) % 2 === 0 ? 'Na' : 'Cl';
        ions.push({
          id: idCounter++,
          type: type,
          r: type === 'Na' ? 7 : 9,
          x: Math.random() * (width || 300) * 0.8 + 20,
          y: Math.random() * (height || 200) * 0.4 + 120,
          vx: (Math.random() - 0.5) * 1.5,
          vy: (Math.random() - 0.5) * 1.5,
          targetCol: c,
          targetRow: r
        });
      }
    }

    const waters = [];
    const waterCount = 36;
    for (let i = 0; i < waterCount; i++) {
      waters.push({
        x: Math.random() * (width || 300) * 0.85 + 15,
        y: Math.random() * 120 + 80,
        vx: (Math.random() - 0.5) * 2,
        vy: (Math.random() - 0.5) * 2,
        angle: Math.random() * Math.PI * 2,
        vRot: (Math.random() - 0.5) * 0.05,
        isGas: false,
        fade: 1.0
      });
    }

    function setTemp(t) {
      currentTemp = Math.round(t);
      tempSlider.value = currentTemp;
      tempDisplay.textContent = currentTemp + '°C';
      
      if (currentTemp >= 95) {
        statusBadge.textContent = 'Steam Escapes • Salt Remains';
        btn100.classList.add('active');
        btn20.classList.remove('active');
      } else if (currentTemp <= 30) {
        statusBadge.textContent = 'Liquid Solution';
        btn20.classList.add('active');
        btn100.classList.remove('active');
      } else {
        statusBadge.textContent = 'Heating...';
        btn20.classList.remove('active');
        btn100.classList.remove('active');
      }
    }

    tempSlider.addEventListener('input', (e) => setTemp(e.target.value));
    btn20.addEventListener('click', () => setTemp(20));
    btn100.addEventListener('click', () => setTemp(100));

    function drawWater(x, y, angle, alpha = 1.0) {
      ctx.save();
      ctx.globalAlpha = alpha;
      ctx.translate(x, y);
      ctx.rotate(angle);

      // Hydrogens (white/light blue)
      ctx.fillStyle = '#93c5fd';
      ctx.beginPath();
      ctx.arc(-5, -4, 3.5, 0, Math.PI * 2);
      ctx.arc(5, -4, 3.5, 0, Math.PI * 2);
      ctx.fill();

      // Oxygen (blue)
      ctx.fillStyle = '#2563eb';
      ctx.beginPath();
      ctx.arc(0, 2, 5.5, 0, Math.PI * 2);
      ctx.fill();

      ctx.restore();
    }

    function drawIon(ion) {
      ctx.save();
      ctx.beginPath();
      ctx.arc(ion.x, ion.y, ion.r, 0, Math.PI * 2);
      if (ion.type === 'Na') {
        ctx.fillStyle = '#10b981';
        ctx.fill();
        ctx.fillStyle = '#ffffff';
        ctx.font = 'bold 9px sans-serif';
        ctx.textAlign = 'center';
        ctx.textBaseline = 'middle';
        ctx.fillText('+', ion.x, ion.y + 0.5);
      } else {
        ctx.fillStyle = '#f97316';
        ctx.fill();
        ctx.fillStyle = '#ffffff';
        ctx.font = 'bold 11px sans-serif';
        ctx.textAlign = 'center';
        ctx.textBaseline = 'middle';
        ctx.fillText('−', ion.x, ion.y);
      }
      ctx.restore();
    }

    function animate() {
      ctx.clearRect(0, 0, width, height);

      const boilFactor = Math.max(0, (currentTemp - 20) / 80); // 0 at 20°C, 1 at 100°C
      const speedMult = 0.5 + boilFactor * 2.2;

      // Draw container walls / bottom
      ctx.strokeStyle = '#94a3b8';
      ctx.lineWidth = 3;
      ctx.beginPath();
      ctx.moveTo(16, 20);
      ctx.lineTo(16, height - 16);
      ctx.lineTo(width - 16, height - 16);
      ctx.lineTo(width - 16, 20);
      ctx.stroke();

      // Draw liquid level line (drops as water boils off)
      const liquidLevel = (height - 30) - (1 - boilFactor) * (height * 0.55);
      if (boilFactor < 0.98) {
        ctx.fillStyle = 'rgba(239, 246, 255, 0.45)';
        ctx.fillRect(18, liquidLevel, width - 36, (height - 16) - liquidLevel);

        ctx.strokeStyle = 'rgba(96, 165, 250, 0.4)';
        ctx.lineWidth = 1.5;
        ctx.setLineDash([4, 4]);
        ctx.beginPath();
        ctx.moveTo(18, liquidLevel);
        ctx.lineTo(width - 18, liquidLevel);
        ctx.stroke();
        ctx.setLineDash([]);
      }

      // Heat source glow at bottom when hot
      if (boilFactor > 0.1) {
        const glow = ctx.createLinearGradient(0, height - 16, 0, height);
        glow.addColorStop(0, `rgba(239, 68, 68, ${boilFactor * 0.4})`);
        glow.addColorStop(1, 'rgba(239, 68, 68, 0)');
        ctx.fillStyle = glow;
        ctx.fillRect(16, height - 16, width - 32, 16);
      }

      // Update & render Ions
      const latticeCenterX = width / 2;
      const latticeBaseY = height - 28;

      ions.forEach(ion => {
        if (boilFactor > 0.6) {
          // Attract towards solid lattice
          const targetX = latticeCenterX + (ion.targetCol - (cols - 1) / 2) * latticeSpacing;
          const targetY = latticeBaseY - (rows - 1 - ion.targetRow) * latticeSpacing;
          const blend = (boilFactor - 0.6) / 0.4;

          ion.x += (targetX - ion.x) * (0.05 + blend * 0.1);
          ion.y += (targetY - ion.y) * (0.05 + blend * 0.1);

          // Small vibration
          ion.x += (Math.random() - 0.5) * (1 + blend * 1.5);
          ion.y += (Math.random() - 0.5) * (1 + blend * 1.5);
        } else {
          // Free aqueous ions
          ion.x += ion.vx * speedMult;
          ion.y += ion.vy * speedMult;

          // Contain inside liquid area
          if (ion.x < 30) { ion.x = 30; ion.vx *= -1; }
          if (ion.x > width - 30) { ion.x = width - 30; ion.vx *= -1; }
          if (ion.y < liquidLevel + 10) { ion.y = liquidLevel + 10; ion.vy *= -1; }
          if (ion.y > height - 30) { ion.y = height - 30; ion.vy *= -1; }
        }
        drawIon(ion);
      });

      // Update & render Water molecules
      waters.forEach(w => {
        w.angle += w.vRot * speedMult;

        if (boilFactor > 0.4) {
          // Rising steam behavior
          w.vy -= 0.08 * boilFactor;
          w.y += w.vy * speedMult;
          w.x += w.vx * (1 + boilFactor);

          // Escaping through the top
          if (w.y < -15) {
            w.y = height - 35;
            w.x = Math.random() * (width - 60) + 30;
            w.vy = (Math.random() - 0.5) * 1.5;
            w.vx = (Math.random() - 0.5) * 1.5;
          }
        } else {
          // Liquid state wander
          w.x += w.vx * speedMult;
          w.y += w.vy * speedMult;

          if (w.x < 25) { w.x = 25; w.vx *= -1; }
          if (w.x > width - 25) { w.x = width - 25; w.vx *= -1; }
          if (w.y < liquidLevel) { w.y = liquidLevel; w.vy *= -1; }
          if (w.y > height - 25) { w.y = height - 25; w.vy *= -1; }
        }

        // Fading slightly if high up steam
        let alpha = 1.0;
        if (w.y < 35) alpha = Math.max(0.2, w.y / 35);

        drawWater(w.x, w.y, w.angle, alpha);
      });

      requestAnimationFrame(animate);
    }

    animate();
  </script>
</body>
</html>

UK-GCSE-SCIENCE-CHEM-CA-01-03

Aligned learning resources

Related diagrams