@charset "UTF-8";
:root{--ink:#193e3b;--muted:#657d75;--green:#21705d;--pale:#e6f0e8;--line:#d8e2d9;--paper:#f7f8f2;--orange:#c97944;font-family:Inter,"Segoe UI","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--paper);font-synthesis:none}*{box-sizing:border-box}body{margin:0}button,input{font:inherit}button{cursor:pointer;color:inherit;border:1px solid var(--line);background:#fff;border-radius:8px;transition:background .15s,transform .15s}button:hover{background:#edf4eb}button:active{transform:translateY(1px)}button:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #dfaa4c;outline-offset:3px}button:disabled{opacity:.42;cursor:default}button.selected,button.active{background:var(--ink);color:white;border-color:var(--ink)}header{height:70px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 4vw}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink);font-weight:700}.brand-icon{font-size:35px;color:var(--green)}.brand small{font-size:10px;letter-spacing:2px;border-left:1px solid var(--line);padding-left:15px;font-weight:500}.header-tools{display:flex;gap:18px;align-items:center}.tag{font-size:12px;color:var(--muted)}.quiet{border:0;background:none;font-size:13px}main{max-width:1640px;margin:auto;padding:30px 4vw 0}.intro{display:flex;align-items:center;justify-content:space-between;margin-bottom:24px}.eyebrow{font-size:11px;letter-spacing:2px;color:var(--muted);font-weight:600}h1{font-size:clamp(28px,3vw,44px);letter-spacing:-1.5px;margin:9px 0 6px;font-weight:650}h1 span{color:#d69d54}.intro p{font-size:15px;margin:0;color:var(--muted)}.mode{display:flex;background:#e7ece3;border-radius:10px;padding:5px;flex-shrink:0}.mode button{border:0;background:transparent;padding:12px 20px;font-size:14px}.mode .selected{background:#fff;color:var(--ink);box-shadow:0 2px 8px #193e3b12}.workspace{display:grid;grid-template-columns:minmax(0,1fr) 334px;border:1px solid #d8e2d9;border-radius:18px;overflow:hidden;background:#fff;box-shadow:0 20px 45px #24483909}.stage-wrap{position:relative;background:radial-gradient(ellipse at 50% 36%,#edf4e8,#dce8df);min-width:0;display:flex;flex-direction:column}.stage-top{padding:18px 20px;display:flex;align-items:center;justify-content:space-between;z-index:2;font-size:12px}.dot{display:inline-block;width:7px;height:7px;background:#468b70;border-radius:50%;margin-right:5px}.small{padding:8px 11px;background:#ffffffb8;font-size:12px}.stage-top button{margin-left:4px}.stage-top>div{display:flex}#stage{height:440px;min-height:340px;flex:1;position:relative;overflow:hidden}canvas{display:block;width:100%;height:100%;touch-action:none}#loading{position:absolute;inset:0;display:grid;place-items:center;color:var(--muted);padding:28px;text-align:center;z-index:4}.readouts{display:flex;margin:0 22px 12px;gap:12px;justify-content:center}.readouts>div{background:#ffffffa3;border:1px solid #fff9;border-radius:10px;min-width:125px;padding:10px 20px}.readouts span{font-size:10px;letter-spacing:1px;color:var(--muted);display:block;margin-bottom:5px}.readouts strong{font:500 27px "Consolas",monospace;display:block;letter-spacing:-1px}.readouts small{font-size:12px;letter-spacing:0;color:var(--muted)}.readouts .temp{background:var(--ink);color:#e3f8ce}.readouts .temp span,.readouts .temp small{color:#bfd5c5}.stage-foot{padding:0 20px 14px;display:flex;justify-content:space-between;gap:10px;font-size:10px;color:#5e786c}.controls{border-left:1px solid var(--line)}.guide{padding:20px 24px;background:#f0f4eb}.guide>span{font:12px Consolas,monospace;color:var(--green)}h2{font-size:19px;margin:8px 0}.guide p{font-size:12px;line-height:1.7;min-height:20px;margin:7px 0 12px;color:var(--muted)}.steps{display:flex;gap:5px}.steps i{height:3px;background:#d3ded0;flex:1;border-radius:5px}.steps i.done{background:#458d75}.control-body{padding:18px 24px 12px}.field-title{display:flex;font-size:12px;align-items:center;justify-content:space-between;gap:8px;font-weight:650}.field-title span{font-size:10px;font-weight:400;color:var(--muted)}.food-options{display:flex;gap:7px;margin:10px 0 14px}.food-options button{flex:1;font-size:12px;padding:10px 4px;background:#f5f6f0}.food-options .active{background:var(--ink)}.food-options span{font-size:18px;margin-right:5px;color:#cba975}.field-row{display:flex;align-items:center;justify-content:space-between;margin:10px 0 8px;font-size:12px}input[type=number]{border:1px solid var(--line);border-radius:6px;background:#fafbf7;color:var(--ink);padding:7px 9px;width:85px}.action{padding:10px;font-size:12px;width:100%}.secondary{background:#fff}.primary{background:var(--green);color:white;border-color:var(--green)}.primary:hover{background:#195a4a}.actions{display:flex;gap:8px;margin-top:14px}.actions button{flex:1;padding:11px 5px}.toggles{border-top:1px solid var(--line);margin-top:14px;padding-top:10px;display:grid;gap:8px;font-size:11px}.toggles label{display:flex;align-items:center;gap:5px}.toggles span{margin-left:auto;color:var(--muted);font-size:10px}input[type=checkbox]{accent-color:var(--green)}#feedback{font-size:11px;color:var(--green);line-height:1.7;min-height:35px;margin:12px 0 0}#feedback.error{color:#b15425}.text-button{border:none;background:none;padding:8px 0;font-size:11px;color:var(--muted)}#burn-panel{margin-top:12px}.burn-line{display:flex;align-items:center;justify-content:space-between;gap:3px;font-size:11px}.burn-line .small{font-size:10px;padding:5px}progress{width:100%;height:6px;accent-color:var(--orange);margin-top:8px}#burn-panel>small{font-size:9px;color:var(--muted)}#record{margin-top:12px}#labels-layer{position:absolute;inset:0;pointer-events:none}.object-label{position:absolute;transform:translate(-50%,-50%);white-space:nowrap;border-radius:5px;background:#fffC;padding:5px 9px;font-size:10px;color:#315747;border:1px solid #c6d8ca}.object-label:before{content:"";display:inline-block;width:5px;height:5px;border-radius:50%;background:#70a18a;margin-right:5px}#object-note{position:absolute;left:20px;right:20px;bottom:120px;background:#173e3cf0;color:#fff;padding:14px 18px;border-radius:9px;font-size:12px;line-height:1.7;z-index:5;pointer-events:none}.notebook{padding:30px 0 20px}.section-head{display:flex;justify-content:space-between;align-items:center}.section-head h2{font-size:24px;margin-bottom:22px}.section-head h2 span{font-size:11px;font-weight:400;margin-left:12px;color:var(--muted)}.results-grid{display:grid;grid-template-columns:1fr 1fr;gap:32px}.calculation,.compare{border-top:1px solid var(--line);padding-top:18px}.formula{font-size:19px;letter-spacing:.4px;margin-top:16px}.calculation p,.compare p{font-size:11px;color:var(--muted);line-height:1.8}.calc-result{background:#eaf0e3;padding:14px 17px;margin:14px 0;font-size:12px;line-height:1.9;border-radius:8px}.calc-result strong{color:var(--green);font-size:16px}.answer-row{display:flex;gap:10px;margin-top:8px}.answer-row input{width:100%;min-width:0}.answer-row button{flex-shrink:0}#check-area label{font-size:11px}.bars{min-height:90px;padding-top:15px}.bar-row{display:grid;grid-template-columns:85px 1fr 84px;gap:10px;align-items:center;font-size:11px;margin:10px 0}.bar-track{height:17px;background:#e4e9df;border-radius:3px;overflow:hidden}.bar-fill{background:#6b9981;height:100%;border-radius:3px}.bar-row small{display:block;font-size:9px;color:var(--muted)}.table-scroll{overflow:auto;margin-top:22px;border:1px solid var(--line);border-radius:9px}table{border-collapse:collapse;width:100%;white-space:nowrap;font-size:11px;text-align:left}th{background:#eef2e9;color:#65756b;font-size:10px;font-weight:500}td,th{padding:13px 15px;border-bottom:1px solid var(--line)}tr:last-child td{border-bottom:0}.empty{font-size:12px;color:var(--muted);line-height:2}.table-scroll .empty{text-align:center;padding:26px}.science{border-block:1px solid var(--line);padding:18px 0;font-size:13px}.science summary{cursor:pointer;display:flex;justify-content:space-between;gap:15px}.science summary span{font-size:11px;color:var(--muted)}.science-grid{display:grid;grid-template-columns:1fr 1fr;gap:35px;padding:10px 0}.science p{font-size:12px;color:var(--muted);line-height:1.9}.science h3{font-size:14px}.science a{color:var(--green)}footer{display:flex;justify-content:space-between;padding:22px 0 30px;font-size:10px;color:var(--muted)}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}[hidden]{display:none!important}body:fullscreen{overflow:auto}
#stage canvas{position:absolute;inset:0;z-index:1}#labels-layer{z-index:2}#stage{flex:1 1 440px}
.controls .action,.controls .field-row{font-size:13px}.controls .guide p{font-size:13px}.object-label{font-size:11px}
:root:fullscreen header{height:54px}:root:fullscreen main{padding-top:12px}:root:fullscreen .intro,:root:fullscreen .notebook,:root:fullscreen .science,:root:fullscreen footer{display:none}:root:fullscreen .workspace{height:calc(100dvh - 80px)}:root:fullscreen .controls{overflow:auto}:root:fullscreen #stage{min-height:0}:root:fullscreen .stage-wrap{min-height:0}
@media(min-width:1600px){#stage{min-height:495px}.workspace{grid-template-columns:minmax(0,1fr) 360px}.control-body{padding:20px 28px}.action{padding:12px}.guide{padding:24px 28px}}
@media(max-width:900px){header{padding:0 22px}.brand small{display:none}main{padding:24px 20px 0}.workspace{grid-template-columns:minmax(0,1fr) 300px}.control-body{padding:16px}.guide{padding:18px 16px}.readouts{gap:6px;margin-inline:10px}.readouts>div{min-width:95px;padding:10px}.stage-foot{flex-direction:column;font-size:9px}.intro h1{font-size:32px}.mode button{padding:11px 12px}.intro p{font-size:12px}}
@media(max-width:700px){header{height:58px;padding:0 16px}.brand{font-size:12px;gap:8px}.brand-icon{font-size:27px}.tag{display:none}.header-tools{gap:0}.quiet{font-size:11px}main{padding:22px 14px 0}.intro{display:block;margin-bottom:18px}.intro h1{font-size:32px}.eyebrow{font-size:9px;letter-spacing:1px}.intro p{font-size:12px}.mode{margin-top:18px;display:flex;width:100%}.mode button{flex:1;padding:10px}.workspace{display:flex;flex-direction:column;border-radius:12px}.stage-top{padding:13px;font-size:10px}.stage-top .small{font-size:10px;padding:7px}#stage{height:340px;min-height:340px;flex:auto}.readouts>div{flex:1;min-width:0;padding:8px 12px}.readouts strong{font-size:23px}.readouts span{font-size:9px;letter-spacing:0}.stage-foot{padding:0 12px 12px;gap:4px}.controls{border-left:0;border-top:1px solid var(--line)}.guide{padding:16px 20px}.guide h2{font-size:18px}.guide p{margin:6px 0 10px}.control-body{padding:18px 20px}.field-title,.field-row,.action{font-size:13px}.food-options button{font-size:13px;padding:12px}.toggles{font-size:12px}.action{padding:12px}.results-grid,.science-grid{grid-template-columns:1fr;gap:22px}.section-head h2{font-size:22px}.formula{font-size:17px}.science summary span{font-size:9px}footer{flex-direction:column;gap:8px;line-height:1.6}#object-note{bottom:118px;font-size:11px}.bar-row{grid-template-columns:82px 1fr 75px}.notebook{padding-top:24px}}
/* Classroom revision: readable controls and one-screen primary workflow. */
header{height:54px}main{padding-top:16px}.intro{margin-bottom:16px}h1{font-size:34px;margin:4px 0}.intro .eyebrow{display:none}.intro p{font-size:14px}.workspace{grid-template-columns:minmax(0,1fr) 350px}.guide{padding:14px 20px}.guide h2{font-size:19px;margin:6px 0}.guide p{margin:6px 0 10px}.control-body{padding:14px 20px 8px}.field-title{font-size:14px}.food-options{margin:8px 0 12px}.food-options button{font-size:15px;padding:10px 5px}.field-row{gap:8px;margin:8px 0}.field-row label{flex:1}.field-row input{width:72px;font-size:16px}.inline-action{padding:9px 12px;font-size:14px}.controls .action{font-size:15px;padding:11px 4px}.controls .field-row{font-size:14px}.toggles{font-size:14px;padding-top:8px;margin-top:12px}.toggles span{font-size:10px}.toggles input{width:16px;height:16px}.actions{margin-top:12px}#feedback{font-size:13px;line-height:1.55;margin-top:10px;min-height:38px}.text-button{font-size:13px}.stage-top{padding:12px 16px;font-size:13px}.small{font-size:13px}.object-label{font-size:13px;padding:5px 8px}.readouts span{font-size:12px;letter-spacing:0}.readouts strong{font-size:29px}.stage-foot{font-size:11px}.stage-foot>span:last-child{display:none}#stage{height:365px;min-height:365px;flex-basis:365px}.readouts{margin-bottom:10px}.zoom-tools{position:absolute;left:16px;bottom:120px;display:grid;gap:5px}.zoom-tools button{width:36px;height:36px;font-size:22px;background:#fffB}.calculation p,.compare p,.science p{font-size:14px}.calc-result{font-size:14px}#check-area label{font-size:14px}table{font-size:13px}th{font-size:12px}.bar-row{font-size:13px}.bar-row small{font-size:11px}.mode button{font-size:16px}.readouts>div{padding:9px 20px}
@media(min-width:1600px){#stage{min-height:490px}.workspace{grid-template-columns:minmax(0,1fr) 380px}.guide{padding:18px 24px}.control-body{padding:20px 24px}.controls .action,.controls .field-row,.toggles,.food-options button{font-size:17px}.guide p,#feedback{font-size:15px}}
@media(max-width:900px){.workspace{grid-template-columns:minmax(0,1fr) 320px}.control-body{padding:12px 14px}.guide{padding:14px}.readouts>div{padding:9px 10px}}
@media(max-width:700px){header{height:54px}main{padding:16px 12px 0}.intro{margin-bottom:14px}h1{font-size:30px}.intro p{font-size:13px}.mode{margin-top:12px}.workspace{display:flex}.stage-top{padding:10px;font-size:11px;gap:6px}.stage-top .small{padding:8px 6px;font-size:11px}.stage-top>span{max-width:85px}.stage-top>div{gap:3px}.stage-top button{margin:0}.stage-foot{font-size:10px}#stage{height:325px;min-height:325px;flex:0 0 325px}.object-label{font-size:11px}.readouts{margin-inline:10px;gap:5px}.readouts strong{font-size:24px}.readouts span{font-size:10px}.readouts>div{padding:9px}.control-body{padding:16px 20px 10px}.guide{padding:15px 20px}.zoom-tools{left:12px;bottom:117px}.controls .action,.toggles,.food-options button{font-size:15px}.field-row input{width:76px}.bar-row{grid-template-columns:82px 1fr 72px}:root:fullscreen .workspace{height:auto}:root:fullscreen #stage{min-height:290px}:root:fullscreen .controls{overflow:visible}:root:fullscreen .stage-wrap{flex:0 0 auto}}
/* Projection: promote essential text instead of shrinking the entire interface. */
.workspace{grid-template-columns:minmax(0,1fr) 380px}.mode button{font-size:18px}.controls .field-row,.food-options button,.controls .action,.inline-action,.toggles{font-size:17px}.field-title{font-size:16px}.controls .guide p{font-size:14px}.guide h2{font-size:20px}.guide>span{font-size:12px}.guide{padding:12px 20px}.guide p{margin:4px 0 8px}.guide .steps{margin-top:8px}.field-row input{font-size:18px;width:80px}.field-row{margin:8px 0}.food-options{margin-bottom:10px}.food-options button{padding:9px 5px}.toggles span{display:none}#feedback{font-size:16px;line-height:1.55;min-height:48px;margin:10px 0 0}.text-button{font-size:15px;padding:8px 0}.readouts span{font-size:14px}.readouts strong{font-size:32px}.stage-top{font-size:15px}.stage-top .small{font-size:14px}.object-label{font-size:14px}.stage-foot{font-size:12px}.quiet{font-size:15px}.header-tools{gap:14px}.header-tools .small{font-size:15px}#record{margin-top:0}.controls:has(#burn-panel:not([hidden])) .guide p{display:none}#burn-panel{margin-top:8px}.burn-line{font-size:14px}.burn-line .small{font-size:12px;padding:7px}#burn-panel>small{font-size:11px}.controls:has(#burn-panel:not([hidden])) #feedback{font-size:14px;min-height:22px}.science summary{font-size:14px}.science{padding:12px 0;margin-top:12px}.science summary span{font-size:12px}footer{padding:12px 0 18px}.notebook{padding-top:8px}:root:fullscreen.notebook-view .notebook{display:block}:root:fullscreen.notebook-view .intro{display:flex}
@media(max-width:1100px) and (min-width:701px){.workspace{grid-template-columns:minmax(0,1fr) 355px}.control-body{padding-inline:15px}.guide{padding-inline:15px}.controls .field-row,.food-options button,.controls .action,.inline-action,.toggles{font-size:16px}.stage-top{flex-wrap:wrap;gap:7px}.object-label{font-size:12px}}
@media(max-width:700px){header{padding:0 12px}.brand{font-size:12px}.brand-icon{display:none}.header-tools{gap:5px}.header-tools .small,.quiet{font-size:12px;padding:7px}.intro h1{font-size:29px}.mode button{font-size:17px}.workspace{display:flex}.stage-top{font-size:11px}.stage-top .small{font-size:11px}.object-label{font-size:11px}.readouts span{font-size:10px}.readouts strong{font-size:25px}.field-title{font-size:15px}.controls .field-row,.controls .action,.food-options button,.toggles,.inline-action{font-size:16px}#feedback{font-size:15px}.science summary{font-size:13px}.science summary span{font-size:10px}.stage-foot{font-size:10px}.field-row input{width:72px}.control-body{padding-inline:16px}.guide{padding-inline:16px}.section-head{align-items:flex-start;gap:12px}.section-head>div:last-child{display:grid;gap:6px}.section-head h2 span{display:block;margin:5px 0}.science-grid{gap:12px}}
.zoom-tools{z-index:3}
:root:fullscreen body.notebook-view .notebook{display:block}:root:fullscreen body.notebook-view .intro{display:flex}
.zoom-tools{top:74px;bottom:auto}.readouts strong{white-space:nowrap}.calculation .field-title,.compare .field-title{font-size:18px}.calc-result{font-size:16px}.formula{font-size:21px}.bar-row{grid-template-columns:115px 1fr 84px;font-size:15px}.bar-row small{font-size:12px;line-height:1.5}.bar-track{height:20px}table{font-size:14px}th{font-size:13px}
@media(max-width:700px){.bar-row{grid-template-columns:104px 1fr 70px;font-size:14px}.formula{font-size:18px}.calculation .field-title,.compare .field-title{font-size:16px}.compare .field-title{align-items:flex-start;flex-direction:column}}
@media(max-width:350px){.readouts strong{font-size:22px}.readouts small{font-size:10px}.readouts>div{padding:8px 7px}.readouts span{font-size:9px}}
/* 1.0.1: dark classroom palette, light text and restrained instrument highlights. */
:root{color-scheme:dark;--ink:#edf3f7;--muted:#b4c4d0;--green:#83dfba;--pale:#21332f;--line:#394958;--paper:#10171f;--orange:#e8b16d}
header{background:#131d27}.brand-icon{color:#83dfba}.workspace{background:#1b2733;border-color:var(--line);box-shadow:0 18px 42px #0003}.stage-wrap{background:radial-gradient(ellipse at 50% 38%,#293b4c 0%,#1b2938 65%,#17222f 100%)}.controls{background:#1b2733}.guide{background:#233240}.dot{background:#83dfba}.steps i{background:#455665}.steps i.done{background:#83dfba}
button,.small,.secondary,.food-options button,.zoom-tools button{background:#283848;color:#edf3f7;border-color:#516677}button:hover,.small:hover,.secondary:hover,.food-options button:hover,.zoom-tools button:hover{background:#374d60}.quiet,.text-button{background:transparent}.quiet:hover,.text-button:hover{background:#283848}.mode{background:#1e2b37}.mode button{background:transparent;color:#dce7ef}.mode button:hover{background:#2d4050}.mode .selected{background:#36586a;color:#fff;box-shadow:inset 0 0 0 1px #86b5c7}.food-options .active,.food-options .active:hover{background:#2b6254;color:#fff;border-color:#8cddbc}.food-options span{color:#edc991}.primary{background:#326c59;border-color:#82c9ab;color:#fff}.primary:hover{background:#3c8069}.primary:disabled{background:#283e39;border-color:#516d63;color:#bdccc6;opacity:1}button:disabled{opacity:.65}
input[type=number]{background:#141f2b;border-color:#526879;color:#fff}input::placeholder{color:#acbdc9;opacity:1}input[type=checkbox]{accent-color:#83dfba}.readouts>div{background:#152330;border-color:#475c6d}.readouts strong{color:#fff}.readouts .temp{background:#112b2c;border-color:#548881;color:#c2ffe8}.readouts .temp strong{color:#c2ffe8}.readouts .temp span,.readouts .temp small{color:#c6e4dc}.readouts span,.readouts small,.stage-foot{color:#c0d0dc}.object-label{background:#132231ed;border-color:#617e93;color:#f0f6fa}.object-label:before{background:#95e1c0}#object-note{background:#102333f5;border:1px solid #68869b;color:#f4f8fa}#feedback{color:#a0ebce}#feedback.error{color:#ffba94}
.calc-result{background:#203b34;color:#edf5f1}.calc-result strong{color:#b4f5d6}.bar-track{background:#2b3d4d}.bar-fill{background:#83cbae}.table-scroll{background:#17232e}th{background:#263847;color:#d5e1e9}.science a{color:#a1e8cf}.science summary{color:#edf3f7}button:focus-visible,input:focus-visible,summary:focus-visible{outline-color:#ffd18e}::selection{background:#547d89;color:#fff}

/* Display-only switch; no scene rebuild or experiment reset. */
.stage-top{flex-wrap:wrap;gap:6px}.stage-top>div{flex-wrap:wrap;gap:4px}.stage-top button{margin:0;min-height:44px}#display-mode[aria-pressed=true]{background:#36586a;color:#fff;border-color:#9ec5d7}.stage-wrap.soft-display{background:radial-gradient(ellipse at 50% 38%,#667985,#485d6d)}.soft-display .stage-top>span,.soft-display .stage-foot{color:#fff}.soft-display .object-label{background:#132231f5}
@media(max-width:700px){.stage-top>div{width:100%}#display-mode{flex:1 0 100%;font-size:14px}.stage-top>div>button:not(#display-mode){flex:1}.zoom-tools{top:158px}}

/* 1.0.2: camera tools beside the canvas, never over instruments. */
.stage-view{display:flex;flex:1;min-height:0;align-items:stretch}#stage{min-width:0;flex:1 1 auto}.zoom-tools{position:static;align-self:center;display:flex;flex-direction:column;width:94px;flex-shrink:0;padding:8px;gap:7px}.zoom-tools button{width:100%;height:auto;min-height:44px;padding:8px 3px;font-size:14px;line-height:1.35}.zoom-tools button small{font-size:12px;margin-left:4px}#drag-mode[aria-pressed=true]{background:#36586a;border-color:#ffd18e;color:#fff}.object-label.selected-object{border-color:#ffd18e;box-shadow:0 0 0 1px #ffd18e}.stage-foot{padding-bottom:6px}.gesture-help{margin:0 16px 10px;font-size:13px;color:#d6e3ed}.gesture-help summary{cursor:pointer;min-height:30px;padding:5px 0}.gesture-help p{font-size:13px;line-height:1.7;margin:4px 0 8px}#object-note{bottom:145px}.stage-top>div{align-items:center}
@media(max-width:700px){.stage-view{flex-direction:column}.zoom-tools{align-self:stretch;flex-direction:row;width:auto;padding:6px 10px}.zoom-tools button{flex:1;min-width:0;font-size:12px}.zoom-tools button small{display:block;margin:0}.stage-top #display-mode{flex:1 1 auto}.stage-top>div>button:not(#display-mode){flex:0 0 auto}#stage{flex:0 0 325px}.gesture-help{margin-inline:12px}.stage-foot{font-size:12px}#object-note{bottom:173px}}

/* Grade 7: one clear action at a time, with a readable illustrated notebook. */
.workspace{grid-template-columns:minmax(0,1fr) 420px}.guide{padding:18px 22px}.guide>span{font-size:17px;font-weight:700;color:#a6eacb}.guide h2{font-size:26px;line-height:1.3;margin:8px 0}.controls .guide p,.controls:has(#burn-panel:not([hidden])) .guide p{display:block;font-size:19px;line-height:1.55;margin:8px 0}.guide #step-why{color:#c0d1df;font-size:17px;border-top:1px solid #536371;padding-top:10px;margin-bottom:0}.steps{list-style:none;margin:12px 0 0;padding:0;display:flex;gap:4px}.steps li{flex:1;font-size:14px;line-height:1.5;text-align:center;padding:5px 1px;border-radius:5px;background:#192733;color:#bacad6}.steps li.current{background:#3e705c;color:white;outline:1px solid #a7e2c4;font-weight:700}.steps li.done{color:#a7e2c4}.control-body{padding:16px 22px}.field-title,.controls .field-row,.food-options button,.inline-action,.controls .action,.toggles{font-size:21px}.field-title span{font-size:16px}.food-options button{padding:12px 5px}.food-options span{font-size:22px}.field-row input{font-size:23px;width:92px;padding:9px}.inline-action{min-height:48px;padding:8px 12px;font-weight:700}.field-row{margin:14px 0}.actions{gap:10px}.controls .action{min-height:52px;font-weight:700}.toggles{border:0;margin:0;padding:0;gap:12px}.toggles input{width:21px;height:21px;flex-shrink:0}.toggles label{min-height:44px}.toggles:has(label:only-child){margin-top:0}#feedback,.controls:has(#burn-panel:not([hidden])) #feedback{font-size:19px;line-height:1.6;min-height:0;margin:12px 0}.setup-summary{font-size:17px;line-height:1.7;color:#c5d5e1;margin:0 0 12px}.text-button{font-size:18px;min-height:44px}.burn-line{font-size:19px;flex-wrap:wrap}.burn-line .small{font-size:17px;min-height:44px}#burn-panel>small{font-size:16px;line-height:1.6;display:block}.current-action{outline:2px solid #b4f3ce;outline-offset:3px}.notebook-launch{display:flex;align-items:center;gap:13px;width:100%;text-align:left;padding:14px;margin:16px 0 3px;border:1px solid #68869b;background:#273d4c}.notebook-launch strong{font-size:22px;display:block}.notebook-launch small{font-size:17px;display:block;line-height:1.6;color:#c5dce6}.notebook-launch>span:nth-child(2){flex:1}#notebook-count{font-size:17px;background:#0e202e;border-radius:20px;padding:2px 8px;margin-left:5px}.book-icon{width:34px;height:34px;stroke:currentColor;stroke-width:1.8;fill:none;flex-shrink:0}.action .book-icon{vertical-align:middle;margin-right:8px;width:26px;height:26px}.notebook-launch.has-new,.next-action{border-color:#ffe0a0!important;background:#3d5142!important;animation:notebook-glow 2.4s ease-in-out infinite}.notebook-launch.has-new .book-icon{color:#ffe0a0;filter:drop-shadow(0 0 6px #ffcf7a)}@keyframes notebook-glow{50%{box-shadow:0 0 0 3px #f7ce7544,0 0 24px #f7ce7540}}@media(prefers-reduced-motion:reduce){.notebook-launch.has-new,.next-action{animation:none;box-shadow:0 0 0 2px #ffe0a0}}
#notebook-dialog{width:min(1160px,94vw);max-width:94vw;max-height:92dvh;margin:auto;padding:0 30px 28px;border:1px solid #647e91;border-radius:20px;background:#15232f;color:#edf3f7;box-shadow:0 24px 100px #0009;overflow:auto}#notebook-dialog::backdrop{background:#030b12c9;backdrop-filter:blur(4px)}#notebook-dialog .notebook,:root:fullscreen #notebook-dialog .notebook{display:block;padding:0}.notebook-head{position:sticky;top:0;z-index:2;background:#15232ff5;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:22px 0 16px;border-bottom:1px solid #425666;backdrop-filter:blur(8px)}.notebook-kicker{font-size:17px;color:#c0d5e5}.notebook-head h2{font-size:30px;margin:6px 0}.notebook-head h2 span{font-size:18px;font-weight:400;display:inline-block;margin-left:12px}.notebook-head button{font-size:18px;min-height:48px;flex-shrink:0;padding:10px 14px}.trial-banner{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;padding:20px 0;font-size:19px;color:#c4d8e6}.trial-banner strong{font-size:23px;color:#a9edc9}.lesson-card{border:1px solid #425d70;border-radius:14px;padding:22px;margin-bottom:18px;background:#1b2e3d}.lesson-card h3,.notebook .compare h3{font-size:25px;line-height:1.5;display:flex;gap:12px;align-items:center;margin:0 0 16px}.lesson-number{display:inline-grid;place-items:center;background:#83dfba;color:#122b23;width:36px;height:36px;flex-shrink:0;border-radius:50%;font-size:23px}.notebook p,.notebook label{font-size:20px;line-height:1.8}.lesson-card p{margin:12px 0 0}.temperature-story{display:flex;align-items:center;gap:18px}.temperature-story>div{flex:1;background:#102130;border:1px solid #4e6e83;border-radius:12px;padding:16px;text-align:center}.temperature-story span{font-size:19px;display:block;color:#c8dce9}.temperature-story strong{display:block;font-size:40px;line-height:1.4;color:#fff}.temperature-story small{font-size:22px;margin-left:6px}.temperature-story .rise-result{background:#204437;border-color:#82c4a6}.temperature-story .rise-result strong{color:#c0ffdf}.temperature-story .story-arrow{font-size:30px;color:#8fd3e2}.notebook .equation{font-size:28px;font-weight:500;line-height:1.7;overflow-wrap:anywhere}.equation b{color:#b5f4d2}.math-story{display:flex;align-items:center;gap:12px;margin-top:20px}.math-story>span{flex:1;background:#102130;text-align:center;padding:14px 6px;border-radius:10px}.math-story small{font-size:17px;display:block;color:#c6d8e6}.math-story b{font-size:30px;display:block;margin-top:7px}.math-story i{font-style:normal;font-size:26px}.math-story .math-result{background:#244b3c;color:#c0ffdf}.heat-story{display:flex;align-items:center;justify-content:center;gap:20px;margin:20px 0;background:#0f2330;border-radius:10px;padding:18px;font-size:20px;text-align:center}.heat-story strong{color:#c0ffdf}.learning-note{border-left:4px solid #e8c17a;padding:10px 16px;background:#293c45;color:#e4eef4}.notebook .compare{border:0;padding:14px 0}.notebook .compare p{font-size:20px;color:#d7e6ee}.notebook .bar-row{grid-template-columns:210px 1fr 130px;font-size:22px;gap:20px;margin:20px 0}.notebook .bar-row small{font-size:17px;line-height:1.65}.notebook .bar-track{height:30px;background:#314859}.notebook details{margin:18px 0;border:1px solid #526c7f;border-radius:12px;padding:16px 20px}.notebook summary{font-size:21px;font-weight:700;cursor:pointer;min-height:35px}.notebook details label{display:block;margin-top:15px}.notebook input{font-size:23px;padding:12px}.notebook .answer-row button,.record-tools button{font-size:18px;padding:12px}.record-tools{display:flex;gap:10px}.notebook table{font-size:18px}.notebook th{font-size:17px}.notebook .empty,.notebook-empty{font-size:21px;padding:20px}.notebook #notebook-done{font-size:22px;min-height:54px;padding:12px 25px;display:block;margin:24px auto 0}.notebook #answer-feedback{font-size:20px}.controls .actions:has(button:not([hidden])){margin-top:10px}
@media(max-width:1100px) and (min-width:701px){.workspace{grid-template-columns:minmax(0,1fr) 385px}.guide,.control-body{padding-inline:18px}.stage-view{flex-direction:column}.zoom-tools{align-self:stretch;flex-direction:row;width:auto;padding:6px 10px}.zoom-tools button{flex:1;min-width:0}}
@media(max-width:700px){.workspace{display:flex}.guide,.control-body{padding:18px}.guide h2{font-size:25px}.controls .guide p{font-size:19px}.controls .field-row,.food-options button,.controls .action,.toggles,.inline-action{font-size:20px}.steps li{font-size:14px}.field-row input{width:85px;font-size:22px}#notebook-dialog{width:96vw;max-width:96vw;padding:0 14px 20px;max-height:96dvh;border-radius:14px}.notebook-head{padding:14px 0;gap:10px;align-items:flex-start}.notebook-head h2{font-size:23px}.notebook-head h2 span{display:block;margin:3px 0;font-size:17px}.notebook-kicker{font-size:14px}.notebook-head button{font-size:15px;padding:8px;max-width:95px}.lesson-card{padding:16px 12px}.lesson-card h3,.notebook .compare h3{font-size:21px;gap:8px}.lesson-number{width:30px;height:30px;font-size:20px}.notebook p,.notebook label{font-size:18px}.temperature-story{gap:6px;flex-wrap:wrap}.temperature-story>div{padding:12px 5px}.temperature-story .rise-result{flex:1 0 100%}.temperature-story strong{font-size:32px}.temperature-story span{font-size:16px}.temperature-story small{font-size:18px}.math-story{flex-wrap:wrap;gap:7px}.math-story small{font-size:15px}.math-story b{font-size:25px}.math-story i{font-size:20px}.math-story .math-result{flex:1 0 100%}.notebook .equation{font-size:22px}.heat-story{font-size:17px;gap:10px;padding:12px 8px}.notebook .bar-row{grid-template-columns:1fr 95px;gap:8px;font-size:20px}.notebook .bar-row .bar-track{grid-row:2;grid-column:1/-1;height:25px}.notebook .bar-row small{font-size:16px}.notebook details{padding:14px 10px}.notebook summary{font-size:19px}.notebook .compare p{font-size:18px}.notebook #notebook-done{font-size:19px;width:100%}.notebook .answer-row{flex-wrap:wrap}.notebook .answer-row button{width:100%}.trial-banner{font-size:17px}.trial-banner strong{font-size:22px}.notebook .learning-note{padding:10px}}
body[data-guide="0"] .controls [data-guide]:not([data-guide="0"]){display:none}
body[data-guide="1"] .controls [data-guide]:not([data-guide="1"]){display:none}
body[data-guide="2"] .controls [data-guide]:not([data-guide="2"]){display:none}
body[data-guide="3"] .controls [data-guide]:not([data-guide="3"]){display:none}
body[data-guide="4"] .controls [data-guide]:not([data-guide="4"]){display:none}
body:not([data-guide="free"]) .controls .actions{margin-top:8px}body[data-guide="0"] .setup-summary{display:none}

.object-label{pointer-events:auto;cursor:pointer}.object-label:hover{background:#2e4b61}.object-label:focus-visible{outline:2px solid #ffd18e}.guide{padding-block:14px}.control-body{padding-block:12px}.field-row{margin-block:10px}.notebook-launch{margin-top:10px;padding:12px}#feedback{margin-top:8px}header{height:48px}main{padding-top:10px}.intro{margin-bottom:10px}.intro h1{font-size:32px}.controls .actions:empty{display:none}

button,summary{touch-action:manipulation}