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@keyframes fluid-trace{to{stroke-dashoffset:-40}}@keyframes turbine-turn{to{transform:rotate(360deg)}}
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.key-point{padding:12px 15px;border-left:4px solid var(--purple);background:#e9e5f0;color:var(--ink);font-size:14px;line-height:1.55;font-weight:500}
.plant-lab .key-point{margin:18px 10px 10px}
.mini-label,.fig-number,.badge{font-size:10px}
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.story-card p{color:#455442}
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.diagram-scroll svg{min-width:1100px}
#plantDiagram .diagram-label{font-size:13px;font-weight:700;paint-order:stroke;stroke:#f3f5ee;stroke-width:2px}
#plantDiagram .small-text{font-size:12px;fill:#3f4e3e;paint-order:stroke;stroke:#f3f5ee;stroke-width:2px}
#plantDiagram .plant-component:not(.active){opacity:.9}
#plantDiagram .circuit{opacity:.4}
#plantDiagram .circuit.active{opacity:1;stroke-width:8}
.plant-lab .explanation-panel{border-left-width:5px;background:#e5eddd}
.diagram-hint{display:none;margin:0 10px 8px;color:#3f4e3e;font-size:12px;font-weight:700}
@media(max-width:1200px){.diagram-hint{display:block}}
.advanced-note{border:1px solid var(--line);border-radius:5px;padding:10px 13px;font-size:13px;background:#f2f4ec}
.advanced-note summary{cursor:pointer;font-weight:700;color:#374b39}
.advanced-note p{margin:10px 0 0}
.prediction-box{margin:-5px 0 24px;padding:15px 18px;border:1px solid #d3bf8a;border-left:5px solid var(--gold);border-radius:5px;background:#f5efdf}
.prediction-box p{margin:0;font-size:14px;line-height:1.55}
.prediction-box .button-row{margin:11px 0}
.prediction-box #predictionFeedback{font-size:12.5px;color:#594b2a}
.prediction-box [aria-pressed="true"]{background:var(--ink);color:white}
.momentum-layout .button{font-size:12px}
.momentum-lab #energyTakeaway{margin-top:17px;font-size:13px}
.orbital-stage{background:#f5f7f0}
.orbital-stage .canvas-corner,.orbital-stage .canvas-bottom{background:#f5f7f0e8;color:#33452f}
.phase-positive{background:#58319a}
.phase-negative{background:#cb441b}
.recoil-insight{display:flex;gap:15px;align-items:baseline;margin-top:16px;padding:14px 17px;border-left:4px solid var(--purple);background:#e9e5f0;font-size:13px;line-height:1.5}
.recoil-insight[hidden]{display:none}
.recoil-insight strong{white-space:nowrap;color:#57318c}
.energy-scale-lab{background:#26372e;color:#f5f7ef;border-color:#26372e;padding:34px}
.energy-scale-top{display:flex;align-items:end;justify-content:space-between;gap:28px}
.energy-scale-top .mini-label{color:#eacb77}
.energy-scale-top h3{font-size:clamp(27px,3vw,39px);margin:10px 0 0;color:#fff}
.energy-scale-top>p{max-width:260px;margin:0;color:#d5dfd1;font-size:14px;line-height:1.5}
.scale-switch{display:flex;gap:8px;margin:26px 0 20px}
.scale-switch button{border:1px solid #a8b9a2;border-radius:999px;background:transparent;color:#edf2e9;padding:10px 18px;font-size:13px;font-weight:700}
.scale-switch button[aria-pressed="true"]{background:#f1d282;border-color:#f1d282;color:#26372e}
.energy-visual{display:grid;grid-template-columns:minmax(180px,1fr) 110px minmax(240px,1.25fr);align-items:center;gap:15px;min-height:250px;padding:25px 30px;border:1px solid #617769;border-radius:10px;background:radial-gradient(circle at 62% 45%,#405944,#293d33 65%)}
.fuel-sample{display:flex;align-items:center;flex-direction:column;text-align:center}
.fuel-disc{display:grid;place-items:center;width:96px;height:96px;border:2px solid #d6a788;border-radius:50%;box-shadow:0 0 0 10px #d8685226,0 0 42px #d8685259;background:radial-gradient(circle at 35% 28%,#ecaf82,#bd513a 75%);color:#fff;font-size:39px;font-weight:700;line-height:1}
.fuel-sample strong{margin-top:20px;font-size:22px;line-height:1.2}
.fuel-sample small{margin-top:5px;color:#d7e0d1;font-size:12px}
.energy-transfer{display:flex;align-items:center;gap:4px;color:#f2c569;font-size:32px}
.energy-transfer>span:first-child{filter:drop-shadow(0 0 12px #f2c569);font-size:38px}
.transfer-line{height:2px;flex:1;background:#e9bf68}
.energy-output{text-align:left}
.energy-output>span{display:block;color:#e9c76e;font-size:11px;font-weight:800;letter-spacing:1.7px}
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.energy-comparison p{margin:0;font-size:14px;line-height:1.5}
.energy-scale-lab .model-note{color:#ced9cc;margin:17px 0}
.energy-scale-lab .scale-calculation{background:#e6eee1;color:#25372e;border-color:#abc1aa;margin-top:18px}
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@media(max-width:860px){.energy-scale-top{display:block}.energy-scale-top>p{margin:14px 0 0;max-width:550px}.energy-visual{grid-template-columns:minmax(130px,1fr) 75px minmax(180px,1.2fr);padding:23px 18px}.energy-output strong{font-size:48px}}
@media(max-width:600px){.energy-scale-lab{padding:22px 16px}.energy-visual{grid-template-columns:1fr;gap:6px;text-align:center;padding:25px 15px}.energy-transfer{justify-content:center;height:55px}.energy-transfer>*{display:none}.energy-transfer::after{content:"↓";font-size:39px;color:#f2d481}.energy-output{text-align:center}.energy-output strong{font-size:52px}.energy-comparison{gap:13px;padding:16px}.comparison-icon{width:47px;height:47px;font-size:30px}.conservation-summary{grid-template-columns:1fr}.recoil-insight{display:block}.recoil-insight span{display:block;margin-top:5px}}
.atom-basics{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center;padding:28px 32px;border:1px solid #bac6b1;border-radius:7px;background:#f3f5ee}
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.part-dot{display:inline-block;flex:none;width:13px;height:13px;border-radius:50%}
.proton-dot{background:#d86852}.neutron-dot{background:#8970b3}.electron-dot{background:#397568}
.atom-basics-copy .atom-bridge{margin:19px 0 0;padding:13px 16px;border-left:4px solid var(--purple);background:#e9e5f0;font-size:14px!important}
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@media(max-width:760px){.atom-basics{grid-template-columns:1fr;gap:12px;padding:22px 18px}.atom-basics-copy h3{font-size:25px}.atom-basics-figure{max-width:520px;margin:auto}}