/* W450: shared header, navigation, main title scale and footer remain in the site shell. */
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#volume450{--ink:#09094b;--text:#3d5074;--muted:#647796;--line:#d3dfed;--paper:#fff;--soft:#f4f7fb;--blue:#0866ff;--green:#e3ffeb;--green-line:#b8e7c8;--dimension:#10184d;--model-paper:#fff;font:14px/1.45 Arial,Helvetica,sans-serif;color:var(--text);background:var(--paper)}#volume450 *{box-sizing:border-box}#volume450 [hidden]{display:none!important}#volume450 h2,#volume450 h3{color:var(--ink);line-height:1.25;font-weight:700;letter-spacing:-.35px;margin:0 0 12px}#volume450 h2{font-size:20px}#volume450 h3{font-size:17px}#volume450 p{margin:8px 0}#volume450 a{color:var(--blue);text-decoration:none}#volume450 a:hover{text-decoration:underline}#volume450 .intro{font-size:18px;color:var(--ink);margin:2px 0 15px}#volume450 .hint{font-size:12px;line-height:1.5;color:var(--muted)}#volume450 button,#volume450 input,#volume450 select{font:inherit;touch-action:manipulation}#volume450 button{border:1px solid #a2c2ff;background:var(--paper);border-radius:4px;color:var(--blue);padding:8px 12px;cursor:pointer;line-height:1.3}#volume450 button:hover{background:var(--soft);border-color:var(--blue)}#volume450 button.primary,#volume450 .units .selected{background:#0768ff;color:white;border-color:#0768ff}#volume450 button:disabled{opacity:.45;cursor:not-allowed}#volume450 :is(button,input,select,a,summary,svg,.error):focus-visible{outline:3px solid #82b1ff;outline-offset:3px}#volume450 img{display:block;max-width:100%;object-fit:contain}#volume450 input,#volume450 select{color:var(--ink);background:var(--paper);border:1px solid var(--line);border-radius:4px;padding:8px 10px;min-width:0;height:38px}#volume450 input[type=checkbox]{accent-color:#0866ff;width:16px;height:16px;margin:0}
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#volume450 .preferences{border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:13px 0;margin-top:2px}#volume450 .preferences>label{display:flex;justify-content:space-between;align-items:center;gap:12px;color:var(--ink);font-size:14px}#volume450 .preferences>label+label{margin-top:13px}#volume450 .preferences select{width:54%;height:34px;font-size:12px;padding:5px 8px}#volume450 .exact-toggle input{appearance:none;width:42px;height:23px;border:0;border-radius:20px;background:#bdc9d8;padding:0;position:relative;cursor:pointer}#volume450 .exact-toggle input:before{content:'';position:absolute;top:3px;left:3px;width:17px;height:17px;border-radius:50%;background:white;box-shadow:0 1px 2px #60708050}#volume450 .exact-toggle input:checked{background:#0768ff}#volume450 .exact-toggle input:checked:before{left:22px}
#volume450 .worked{margin:15px 0 0}#volume450 .worked h3{margin-bottom:10px}#volume450 .worked dl{margin:0;background:var(--soft);border:1px solid var(--line);border-radius:4px;padding:0 12px}#volume450 .worked dl>div{display:grid;grid-template-columns:24% minmax(0,1fr);gap:10px;padding:17px 0;align-items:center}#volume450 .worked dl>div+div{border-top:1px solid var(--line)}#volume450 .worked dt{font-size:13px;font-weight:bold;color:var(--ink)}#volume450 .worked dd{margin:0;font:15px/1.5 Georgia,'Times New Roman',serif;color:var(--ink);overflow-wrap:anywhere}#volume450 .worked>p{font-size:13px;line-height:1.5;margin:13px 0 0}#volume450 .form-actions,#volume450 .export-actions{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:10px}#volume450 .form-actions{padding-top:26px;margin-top:auto}#volume450 .form-actions>button{width:100%;height:41px;font-weight:700}#volume450 .error{background:#fff2f2;color:#9c2833;border:1px solid #dea1a7;padding:10px;border-radius:4px;font-size:13px}
#volume450 .result-column{border:1px solid var(--green-line);border-radius:5px;background:var(--green);padding:11px;min-width:0;display:flex;flex-direction:column;color:var(--ink)}#volume450 .result-summary{padding:0 6px 0}#volume450 .result-summary h2{font-size:14px;font-weight:400;margin:0 0 1px;letter-spacing:0}#volume450 .volume-value{font-size:43px;line-height:1.15;letter-spacing:-1px;font-weight:700;margin:0!important;color:var(--ink);overflow-wrap:anywhere}#volume450 .volume-value span{font-size:37px}#volume450 .exact-result{font-size:13px;margin:3px 0 9px;overflow-wrap:anywhere}#volume450 .capacity-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin:9px 0}#volume450 .capacity-grid>div{padding:13px 5px;text-align:center;background:var(--paper);border:1px solid var(--line);border-radius:4px;font-size:19px;font-weight:700;min-width:0;overflow-wrap:anywhere}#volume450 .surface-row{display:flex;align-items:center;gap:12px;justify-content:space-between;padding:10px 12px;background:var(--paper);border:1px solid var(--line);border-radius:4px;margin-bottom:13px}#volume450 .surface-row>span{font-size:13px;font-weight:700}#volume450 .surface-row>strong{font-size:25px;letter-spacing:-.5px;white-space:nowrap}#volume450 .surface-row small{font-size:11px;overflow-wrap:anywhere}
#volume450 .model-panel{border:1px solid var(--line);border-radius:4px;background:var(--paper);padding:12px 12px 7px;flex:1;min-width:0;display:flex;flex-direction:column}#volume450 .model-panel .panel-heading{margin:0}#volume450 .model-panel h2{font-size:17px}#volume450 #volumeModel{display:block;width:100%;height:auto;min-height:235px;aspect-ratio:560/390;max-height:370px;cursor:grab;touch-action:none;user-select:none;margin:0 auto}#volume450 #volumeModel.dragging{cursor:grabbing}#volume450 .model-controls{display:flex;align-items:center;gap:13px;flex-wrap:wrap;font-size:11px;color:var(--ink);margin-top:auto}#volume450 .model-controls label{display:flex;align-items:center;gap:7px;cursor:pointer}#volume450 .model-controls button{font-size:11px;padding:5px 8px;border-color:var(--line);color:var(--ink)}#volume450 .model-controls small{margin-left:auto;font-size:10px;color:var(--muted)}#volume450 .model-caption{display:flex;justify-content:space-between;gap:8px;align-items:center;margin-top:5px}#volume450 .model-caption p{font-size:10px;color:var(--muted);margin:0}#volume450 .watermark{width:90px;height:auto;opacity:.4;filter:brightness(.5);pointer-events:none}#volume450 .sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
#volume450 .export-actions{gap:14px;margin:13px 0}#volume450 .export-actions button{height:41px;font-weight:600;color:var(--ink)}#volume450 .export-status:empty{display:none}#volume450 .export-status{font-size:12px;color:var(--ink)}#volume450 .knowledge-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px;align-items:stretch;margin-bottom:13px}#volume450 .unit-lesson>div{display:grid;grid-template-columns:40% minmax(0,1fr);gap:12px;align-items:center}#volume450 .unit-lesson img{width:100%;height:auto}#volume450 .unit-lesson p{font-size:13px;color:var(--ink);margin:0 0 9px}#volume450 .unit-lesson .hint{font-size:12px;color:var(--muted)}#volume450 table{border-collapse:collapse;width:100%;text-align:left;color:var(--ink)}#volume450 th,#volume450 td{border:1px solid var(--line);padding:5px 9px;font-size:12px;line-height:1.25}#volume450 th{font-weight:400}#volume450 thead{background:var(--soft)}#volume450 thead th{font-weight:700}#volume450 .unit-lesson table{margin-top:16px;text-align:center}#volume450 .unit-lesson td{padding:9px;font-size:14px}#volume450 .faq details{border:1px solid var(--line);border-radius:4px;margin-bottom:9px}#volume450 .faq details:last-child{margin-bottom:0}#volume450 .faq summary{font-size:12px;line-height:1.4;cursor:pointer;color:var(--ink);padding:10px 12px;list-style:none;position:relative;padding-right:27px}#volume450 .faq summary::-webkit-details-marker{display:none}#volume450 .faq summary:after{content:'⌄';position:absolute;right:11px;top:9px;font-size:14px;color:var(--ink)}#volume450 .faq details[open]>summary:after{content:'⌃'}#volume450 .faq p{font-size:12px;padding:0 12px 10px;margin:0}
#volume450 .formula-reference{margin-bottom:13px;padding:12px 15px}#volume450 .formula-reference h2{margin-bottom:8px}#volume450 .formula-layout{display:grid;grid-template-columns:3fr 1fr;gap:24px;align-items:start}#volume450 .table-scroll{overflow-x:auto}#volume450 .formula-reference tbody td{font-family:Georgia,'Times New Roman',serif;font-size:14px}#volume450 .formula-layout .hint p{font-size:12px;margin:0 0 10px}#volume450 .sources{margin-bottom:14px;padding:11px 14px 8px}#volume450 .sources h2{margin-bottom:9px}#volume450 .source-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:9px}#volume450 .source-grid>a{display:flex;align-items:center;gap:12px;padding:10px;border:1px solid var(--line);border-radius:4px;color:var(--ink);min-width:0}#volume450 .source-grid img{width:85px;height:43px;flex:none}#volume450 .source-grid strong{display:block;font-size:13px;margin-bottom:3px}#volume450 .source-grid b{display:block;font-size:11px;font-weight:400;line-height:1.3}#volume450 .source-grid small{display:block;font-size:10px;color:var(--muted);line-height:1.4;margin-top:3px}#volume450 .source-note{font-size:10px;text-align:right;color:var(--muted);margin:5px 0 0}#volume450 .related h2{margin-bottom:9px}#volume450 .related-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:11px}#volume450 .related-grid>a{display:flex;align-items:center;gap:12px;border:1px solid var(--line);border-radius:4px;padding:10px 12px;min-height:106px;color:var(--ink);min-width:0}#volume450 .related-grid img{width:104px;height:83px;flex:none}#volume450 .related-grid strong{display:block;font-size:14px;line-height:1.3;margin-bottom:5px}#volume450 .related-grid small{display:block;font-size:12px;line-height:1.4;color:var(--text)}
html:is(.st-master-dark,.st-home-dark,.dark,[data-theme=dark]) #volume450{--ink:#e3ecff;--text:#bfd0ec;--muted:#a1b7d7;--line:#3b5575;--paper:#11273f;--soft:#1c3551;--green:#143e32;--green-line:#39745b;--dimension:#e3ecff;--model-paper:#11273f;--blue:#83b8ff}html:is(.st-master-dark,.st-home-dark,.dark,[data-theme=dark]) #st334Content:has(#volume450)>h1{color:#e3ecff}html:is(.st-master-dark,.st-home-dark,.dark,[data-theme=dark]) #volume450 .shape-card.selected{background:#214461;border-color:#83b8ff}html:is(.st-master-dark,.st-home-dark,.dark,[data-theme=dark]) #volume450 .source-grid img{background:#fff;border-radius:3px;padding:3px}html:is(.st-master-dark,.st-home-dark,.dark,[data-theme=dark]) #volume450 .watermark{filter:drop-shadow(0 1px 1px #000);opacity:.4}html:is(.st-master-dark,.st-home-dark,.dark,[data-theme=dark]) #volume450 .error{background:#442831;color:#ffd1d6;border-color:#965462}
@media(max-width:1100px){#volume450 .shape-card>strong{font-size:12px}#volume450 .shape-card>small{font-size:10px}#volume450 .panel-heading h2{font-size:17px}#volume450 .units button{min-width:32px;padding:6px 7px}#volume450 .capacity-grid>div{font-size:16px}#volume450 .surface-row{gap:9px;padding:9px 8px;flex-wrap:wrap}#volume450 .surface-row strong{font-size:24px}#volume450 .surface-row small{margin-left:auto}#volume450 .source-grid img{width:66px}#volume450 .related-grid img{width:83px}#volume450 .model-controls{gap:8px}}
@media(max-width:850px){#st334Content:has(#volume450){width:calc(100% - 28px)}#volume450 .shape-cards{grid-template-columns:repeat(3,minmax(0,1fr))}#volume450 .shape-card>strong{font-size:14px}#volume450 .shape-card>small{font-size:11px}#volume450 .shape-card{height:134px}#volume450 .studio-grid{grid-template-columns:1fr}#volume450 .form-actions{padding-top:20px}#volume450 .dimension-row{grid-template-columns:30% 1fr;margin:12px 0 16px}#volume450 .worked dl>div{padding:12px 0}#volume450 .source-grid{grid-template-columns:1fr}#volume450 .source-grid img{width:90px}#volume450 .related-grid{grid-template-columns:1fr}#volume450 .related-grid img{width:115px}#volume450 .formula-layout{grid-template-columns:1fr;gap:12px}#volume450 .formula-layout>.hint{display:grid;grid-template-columns:1fr 1fr;gap:12px}#volume450 .surface-row{flex-wrap:nowrap}}
@media(max-width:600px){#volume450 .intro{font-size:15px}#volume450 .shape-cards{gap:7px}#volume450 .shape-card{height:127px}#volume450 .shape-card>img{height:75px;width:104px}#volume450 .shape-card>strong{font-size:11px}#volume450 .shape-card>small{font-size:9px}#volume450 .panel{padding:12px}#volume450 .panel-heading{gap:8px}#volume450 .panel-heading h2{font-size:17px}#volume450 .units button{min-width:29px;padding:6px 5px;font-size:11px}#volume450 .dimension-row{grid-template-columns:30% 1fr}#volume450 .dimension-row label{font-size:12px}#volume450 .worked dl{padding:0 9px}#volume450 .worked dl>div{grid-template-columns:25% 1fr;gap:9px}#volume450 .worked dt{font-size:11px}#volume450 .worked dd{font-size:13px}#volume450 .result-column{padding:9px}#volume450 .result-summary{padding:0 2px}#volume450 .volume-value{font-size:36px}#volume450 .volume-value span{font-size:31px}#volume450 .capacity-grid{gap:7px}#volume450 .capacity-grid>div{font-size:14px;padding:11px 4px}#volume450 .surface-row{flex-wrap:wrap}#volume450 .surface-row>span{font-size:12px}#volume450 .surface-row strong{font-size:22px}#volume450 .surface-row small{width:100%;margin-left:0}#volume450 .model-panel{padding:10px 7px 7px}#volume450 .model-panel h2{font-size:15px}#volume450 #volumeModel{min-height:220px}#volume450 .model-controls small{width:100%;margin-left:0}#volume450 .model-caption{align-items:flex-end}#volume450 .model-caption p{font-size:9px;text-align:right}#volume450 .watermark{width:78px}#volume450 .knowledge-grid{grid-template-columns:1fr}#volume450 h2{font-size:18px}#volume450 .unit-lesson>div{grid-template-columns:40% 1fr;gap:9px}#volume450 .unit-lesson p{font-size:12px}#volume450 .unit-lesson .hint{font-size:11px}#volume450 .unit-lesson td{padding:7px 4px;font-size:12px}#volume450 .formula-layout>.hint{display:block}#volume450 .formula-reference th,#volume450 .formula-reference td{font-size:11px;padding:5px 6px}#volume450 .export-actions{gap:10px}#volume450 .export-actions button{font-size:13px}}
@media(prefers-reduced-motion:reduce){#volume450 *{scroll-behavior:auto!important}}