:root{font-family:Arial,Helvetica,sans-serif;color:#e1e9ef;background:#101923;--ink:#e1e9ef;--muted:#a5b5c3;--line:#2c3a48;--cyan:#61d5f6;--orange:#ff985b;--panel:#16222f;color-scheme:dark}*{box-sizing:border-box}body{margin:0}button,input,select{font:inherit}button,select{cursor:pointer}button{min-height:42px;padding:9px 14px;border:1px solid var(--line);border-radius:5px;background:#1a2937;color:var(--ink);transition:background .15s,border-color .15s}button:hover{background:#263b4d;border-color:#597183}button:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible,a:focus-visible{outline:3px solid var(--cyan);outline-offset:4px}header{display:flex;align-items:center;justify-content:space-between;gap:20px;border-bottom:1px solid var(--line);padding:24px 36px}.brand{display:flex;align-items:center;gap:16px;text-decoration:none;color:var(--ink)}.mark{font-size:34px;letter-spacing:-2px;font-weight:800;position:relative;border-left:4px solid var(--cyan);padding-left:10px}.mark>span{font-size:12px;letter-spacing:0;margin-left:4px;vertical-align:top;color:var(--cyan)}.brand strong{display:block;font-size:19px;margin-bottom:6px}.brand small{font-size:12px;letter-spacing:2px;color:var(--muted)}.header-spec{font:12px monospace;color:var(--muted);letter-spacing:1px}.header-spec i{font-style:normal;padding:0 12px;color:#536a7d}header>button{background:transparent}main{padding:24px 36px;max-width:1700px;margin:auto}.explorer{display:grid;grid-template-columns:minmax(0,1fr) 315px;border:1px solid var(--line);border-radius:9px;overflow:hidden}.viewport{position:relative;min-height:610px;background:radial-gradient(ellipse at 45% 45%,#263c4d 0%,#121f2b 75%);overflow:hidden}#engine{position:absolute;width:100%;height:100%;touch-action:none;cursor:grab}#engine:active{cursor:grabbing}.scene-top{position:absolute;top:25px;left:26px;right:22px;display:flex;align-items:start;justify-content:space-between;gap:20px;pointer-events:none}.eyebrow{font-size:12px;letter-spacing:1.5px;font-weight:600;color:var(--muted)}h1{font-size:42px;letter-spacing:-1px;margin:10px 0 8px;font-weight:500}.scene-top p{margin:0;color:var(--muted);font-size:14px}.view-buttons{display:flex;gap:2px;padding:3px;background:#101c26bb;border:1px solid var(--line);border-radius:6px;pointer-events:auto}.view-buttons button{font-size:12px;min-height:34px;padding:7px 10px;background:transparent;border:0}.view-buttons button[aria-pressed=true]{background:#dbeaf0;color:#142535}.scene-bottom{position:absolute;bottom:18px;left:24px;right:24px;display:flex;align-items:center;justify-content:space-between;pointer-events:none;gap:15px}.scene-bottom>span{font-size:12px;color:var(--muted)}.scene-bottom button{pointer-events:auto;min-width:42px;padding:7px;font-size:22px}.flow-key{position:absolute;bottom:76px;left:24px;display:flex;gap:20px;font-size:12px;color:#c6d3dd;pointer-events:none}.flow-key span,.flow-caption span{display:flex;align-items:center;gap:8px}i.cold,i.core,i.hot{display:inline-block;width:18px;height:3px;border-radius:2px;background:var(--cyan)}i.core{background:#b6bfe5}i.hot{background:var(--orange)}.part-label{position:absolute;pointer-events:none;transform:translate(-50%,-50%);font-size:12px;white-space:nowrap;background:#101c29e8;border:1px solid #526879;border-radius:4px;padding:5px 8px;color:#d8e4ec}.part-label:before{content:'';display:inline-block;width:5px;height:5px;margin-right:6px;border-radius:50%;background:var(--cyan)}aside{background:var(--panel);border-left:1px solid var(--line);padding:26px 22px;display:flex;flex-direction:column}.aside-meta{display:flex;justify-content:space-between;gap:10px}.aside-meta .eyebrow{font-size:12px;letter-spacing:1px}#part-count{font:12px monospace;color:var(--muted);white-space:nowrap}#part-heading{margin:28px 0 0}#part-number{color:var(--cyan);font:14px monospace}#part-title{font-size:29px;letter-spacing:-.5px;line-height:1.12;margin:9px 0 16px;font-weight:500}#part-description{font-size:16px;line-height:1.55;margin:0;color:#c5d2dc;min-height:125px}.fact{border-left:2px solid var(--cyan);padding-left:14px;margin:20px 0}.fact>span{font-size:12px;color:var(--cyan);letter-spacing:1px}.fact p{font-size:14px;line-height:1.5;margin:8px 0 0}.spool-info{padding:16px 0;border-top:1px solid var(--line)}.spool-info .eyebrow{font-size:12px;letter-spacing:1px}.spool-info p{font-size:14px;line-height:1.5;margin:7px 0 0;color:#bfceda}.part-nav{display:flex;justify-content:space-between;gap:8px;margin-top:auto;padding:10px 0 20px}.part-nav button{font-size:14px;flex:1;padding:9px 6px}.shaft-controls{border-top:1px solid var(--line);padding-top:16px}.shaft-controls>label{display:block;font-size:14px;margin-bottom:8px}select{background:#101d29;border:1px solid #405468;color:var(--ink);padding:9px 8px;border-radius:4px;font-size:14px;min-height:42px;max-width:100%;width:100%}.shaft-controls p{font-size:12px;line-height:1.5;color:var(--muted);margin:10px 0 0}.stage-strip{display:grid;grid-template-columns:repeat(5,1fr);margin-top:12px;gap:7px}.stage-strip button{position:relative;text-align:left;padding:15px 13px 12px;background:#14212d;border:1px solid var(--line);font-size:14px}.stage-strip button>span{color:var(--muted);font:12px monospace;margin-right:10px}.stage-strip button small{font-size:12px;display:block;color:var(--muted);letter-spacing:.7px;margin:9px 0 0 27px}.stage-strip button[aria-pressed=true]{background:#203547;border-color:var(--cyan)}.stage-strip button[aria-pressed=true]>span{color:var(--cyan)}.controls{display:grid;grid-template-columns:1.1fr 1fr 1fr auto;align-items:center;gap:28px;padding:26px 0;border-bottom:1px solid var(--line)}.play{display:flex;align-items:end;gap:10px}.play label{font-size:12px;color:var(--muted);display:flex;flex-direction:column;gap:8px;min-width:100px}.primary{background:var(--cyan);border-color:var(--cyan);color:#122536;min-width:98px}.primary:hover{background:#94e6fd;border-color:#94e6fd}.power,.cut{display:flex;flex-direction:column;gap:12px;font-size:14px}.power>span:first-child,.cut>span:first-child{display:flex;justify-content:space-between;gap:10px}output{color:var(--cyan);font:16px 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var(--line);padding-top:20px;display:flex;align-items:start;gap:20px;justify-content:space-between;font-size:12px;color:var(--muted);line-height:1.6}footer>span{white-space:nowrap}footer b{color:var(--cyan);padding:0 8px}footer details{max-width:580px;margin-right:auto}footer summary{cursor:pointer}footer details p{font-size:14px;line-height:1.6}a{color:var(--cyan)}#render-error{position:absolute;top:40%;left:10%;right:10%;padding:20px;background:var(--panel);border:1px solid var(--line);font-size:16px;line-height:1.5}#render-error[hidden]{display:none}@media(min-width:1450px){.viewport{min-height:660px}}@media(max-width:1150px){header{padding:20px}.header-spec{display:none}main{padding:20px}.explorer{grid-template-columns:minmax(0,1fr) 285px}.scene-top{flex-direction:column;gap:15px}.scene-top p{display:none}.controls{grid-template-columns:1fr 1fr 1fr;gap:24px}.toggles{grid-column:1/-1;flex-direction:row;gap:24px}.stage-strip button small{margin-left:0;letter-spacing:0}.stage-strip button>span{display:block;margin-bottom:8px}.model-note{display:none}}@media(max-width:720px){header{padding:16px;gap:10px}.brand{gap:10px}.brand strong{font-size:17px}.brand small{font-size:12px;letter-spacing:1px}.mark{font-size:29px}header>button{font-size:12px;padding:8px 10px}main{padding:12px}.explorer{display:flex;flex-direction:column}.viewport{min-height:455px}.scene-top{left:18px;right:18px;top:18px;flex-direction:row;gap:10px;align-items:start}.scene-top .eyebrow{font-size:12px;letter-spacing:.5px}h1{font-size:30px;margin-top:8px}.view-buttons{flex-direction:column;gap:0}.view-buttons button{font-size:12px;padding:6px 8px;min-height:32px}.flow-key{left:16px;bottom:72px;gap:14px;font-size:12px}.flow-key i{width:12px}.scene-bottom{left:16px;right:16px;bottom:14px}.part-label{font-size:12px;padding:4px 5px}aside{border-left:0;border-top:1px solid var(--line);padding:20px;display:grid;grid-template-columns:1fr 1fr;gap:0 18px}.aside-meta{grid-column:1/-1}#part-heading{grid-column:1/-1;margin-top:18px;display:flex;align-items:baseline;gap:12px}#part-title{font-size:27px;margin:0 0 13px}#part-description{grid-column:1/-1;min-height:0}.fact{grid-column:1/-1;margin:20px 0}.spool-info{grid-column:1/-1}.part-nav{grid-column:1/-1;margin:0;padding-bottom:18px}.shaft-controls{grid-column:1/-1}.stage-strip{grid-template-columns:repeat(5,minmax(0,1fr));gap:4px}.stage-strip button{text-align:center;min-height:77px;font-size:12px;line-height:1.3;padding:10px 2px}.stage-strip button>span{margin:0 0 7px}.stage-strip button small{display:none}.controls{grid-template-columns:1fr 1fr;padding:22px 2px;gap:22px 18px}.play{grid-column:1/-1;justify-content:space-between;align-items:center}.play label{flex-direction:row;align-items:center;font-size:14px;gap:10px}.play select{width:110px}.primary{min-width:120px}.toggles{gap:8px 20px;flex-wrap:wrap}.toggles label{font-size:14px;min-height:36px}.flow-section{padding:22px 2px}.flow-heading>span{display:none}.flow-heading h2{font-size:18px}#flow-diagram{height:215px}.flow-caption{flex-direction:column;gap:9px}footer{padding:17px 2px;flex-wrap:wrap;gap:12px 20px}footer details{margin:0;flex:1;min-width:180px}}@media(prefers-reduced-motion:reduce){button{transition:none}}

.assembly-controls{display:flex;align-items:center;flex-wrap:wrap;gap:18px 28px;padding:18px 0;border-bottom:1px solid var(--line)}.explode-switch{display:flex;align-items:center;gap:9px;min-height:42px;font-size:16px;cursor:pointer}.separation{min-width:180px;max-width:340px;flex:1;font-size:14px}.separation>span{display:flex;justify-content:space-between;gap:16px;margin-bottom:5px}#exploded-note{font-size:12px;line-height:1.5;color:var(--muted)}.assembly-controls [hidden]{display:none}button:disabled,select:disabled,input:disabled{cursor:default;opacity:.5}button:disabled:hover{background:inherit}.controls:has(#play:disabled) .primary{background:var(--cyan)}@media(max-width:720px){.assembly-controls{gap:12px 18px;padding:14px 2px}.separation{min-width:125px}#exploded-note{width:100%}}

.flow-key[hidden]{display:none}

.engine-picker{display:flex;align-items:center;gap:24px;padding:0 0 22px}.engine-picker>label{font-size:14px;display:flex;flex-direction:column;gap:8px;min-width:225px}.engine-picker select{font-size:17px;min-height:48px;background:#203547;border-color:#61d5f6}.engine-picker strong{font-size:16px;font-weight:500}.engine-picker p{font-size:14px;color:var(--muted);line-height:1.5;margin:7px 0 0}.engine-picker>span{margin-left:auto;color:var(--cyan);font-size:14px;text-align:right}.mark>b{font-weight:800}.flow-key [hidden]{display:none}@media(max-width:720px){.engine-picker{align-items:start;gap:14px;flex-wrap:wrap;padding:3px 2px 18px}.engine-picker>label{min-width:100%;width:100%}.engine-picker>div{flex:1;min-width:180px}.engine-picker>span{font-size:12px;max-width:95px}.engine-picker p{margin-bottom:0}}