/* One workbench, shared spacing, controls and surfaces. */
:root{color-scheme:light;--paper:#f5f3ed;--surface:#fffefa;--ink:#203b3a;--muted:#61716a;--line:#d7dfd3;--accent:#315e4d;--soft:#eef2e9;--danger:#973a24}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:14px/1.5 Arial,Helvetica,sans-serif}button,input{font:inherit}button,a,input,summary{-webkit-tap-highlight-color:transparent}a{color:inherit}button,summary{cursor:pointer}header,main,footer{width:min(1440px,calc(100% - 64px));margin:auto}
.site-header{height:62px;display:flex;align-items:center;justify-content:space-between}.brand{font-size:20px;font-weight:700;text-decoration:none;letter-spacing:-1px}.brand span{margin-left:10px;font-size:11px;font-weight:400;letter-spacing:2px}nav a,footer{font-size:12px}nav a,footer a{text-decoration:none}
.workspace{background:var(--surface);border:1px solid var(--line);border-radius:14px;overflow:clip}.workspace-header{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:20px 24px;border-bottom:1px solid var(--line)}h1{margin:0;font-size:24px;line-height:1.2;letter-spacing:-.7px;font-weight:600}.workspace-header p{font-size:12px;color:var(--muted);margin:5px 0 0}h2{font-size:13px;font-weight:600;margin:0}
button{min-height:36px;padding:7px 11px;border:1px solid var(--line);border-radius:6px;color:var(--ink);background:var(--surface);font-size:12px}button:hover{background:#e4eadf;border-color:#a8bba4}button:disabled{opacity:.5;cursor:default}.button{white-space:nowrap}
.workbench{display:grid;grid-template-columns:280px minmax(0,1fr)}.design{padding:22px;border-right:1px solid var(--line)}.design>h2{margin-bottom:22px}.output{min-width:0}.control{margin:0 0 16px}.control-top{display:flex;align-items:center;justify-content:space-between;gap:8px}.control-top label{font-size:12px}.number-wrap{display:flex;align-items:center;gap:5px;font-size:10px;color:var(--muted)}input[type=number]{width:68px;min-height:32px;padding:5px;border:1px solid var(--line);border-radius:5px;background:white;color:var(--ink);text-align:right;font-size:12px}input[type=range]{display:block;width:100%;margin:8px 0 0;accent-color:var(--accent);height:18px;cursor:pointer}.range-ends{display:flex;justify-content:space-between;font-size:10px;color:var(--muted)}input[type=checkbox],input[type=radio]{accent-color:var(--accent);width:14px;height:14px;margin:0;flex:none}input[aria-invalid=true]{border-color:var(--danger);background:#fff0e8}
.core{border:0;padding:0;margin:20px 0 12px}.core legend{font-size:12px;margin-bottom:9px}.core-options{display:flex;border:1px solid var(--line);border-radius:6px;overflow:hidden}.core label{display:flex;align-items:center;justify-content:center;gap:6px;flex:1;font-size:12px;padding:10px 7px;cursor:pointer}.core label+label{border-left:1px solid var(--line)}.core label:has(input:checked){background:var(--soft);color:#244c3d}.core span{font-size:10px;color:var(--muted)}.small{font-size:11px;color:var(--muted);line-height:1.6}#winding{margin:0}.experiments{border-top:1px solid var(--line);margin-top:20px;padding-top:15px}summary{font-size:12px;font-weight:600;list-style-position:inside}summary::marker{color:#748b78}.experiment-buttons{display:grid;gap:6px;margin-top:12px}.experiment-buttons button{text-align:left}#lesson{font-size:12px;color:var(--muted);border-left:2px solid #bb7950;padding-left:10px;margin:14px 0 0}#error{color:var(--danger);font-size:12px;padding:10px;background:#fff0e8;border-radius:5px}
.viewer{background:radial-gradient(ellipse at 50% 45%,#eff4eb,#e5ebdf);min-width:0;position:relative}.viewer-heading{padding:16px 22px 0;display:flex;align-items:center;justify-content:space-between;gap:12px}.badge{border:1px solid #bdcbb6;border-radius:4px;font-size:10px;letter-spacing:.5px;padding:3px 7px}#viewport{height:clamp(290px,40vh,460px);position:relative;touch-action:none}#viewport canvas{display:block;width:100%;height:100%}#loading{position:absolute;left:10%;right:10%;top:38%;text-align:center;font-size:13px;color:var(--muted)}.scene-labels{display:flex;justify-content:space-between;flex-wrap:wrap;gap:4px 18px;padding:0 22px 10px;font-size:10px;color:#475e50}.viewer-controls{border-top:1px solid #cbd6c5;margin:0 22px;padding:12px 0 6px;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:10px 16px}.buttons{display:flex;gap:4px;flex-wrap:wrap}.buttons button{min-width:34px;background:#f9fbf6a6;padding:6px 9px}.toggles{display:flex;flex-wrap:wrap;gap:12px}.toggles label{font-size:11px;display:flex;align-items:center;gap:5px;min-height:32px;cursor:pointer}.viewer-hint{margin:0;padding:3px 16px 12px;text-align:center;font-size:10px;color:#5d725a}
.performance{padding:16px 22px 20px;border-top:1px solid var(--line)}.section-label{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:14px}.section-label>span{font-size:11px;color:var(--muted)}.metrics{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:12px}.metric{min-width:0;padding-left:12px;border-left:1px solid var(--line)}.metric:first-child{padding-left:0;border-left:0}.metric-label{display:block;font-size:11px;margin-bottom:5px;color:var(--muted)}.metric-value{display:block;font-size:22px;letter-spacing:-.5px;font-variant-numeric:tabular-nums;line-height:1.3;overflow-wrap:anywhere}.metric:first-child .metric-value{color:var(--accent);font-weight:600}.metric-unit{display:block;font-size:11px;letter-spacing:0;margin:2px 0 0;color:var(--muted);font-weight:400}.metric-help{display:block;font-size:10px;color:var(--muted);margin-top:5px;line-height:1.4}.stale{opacity:.45}
.chart-panel{border-top:1px solid var(--line)}.chart-panel>summary{padding:15px 22px}.chart-panel>summary>span{float:right;font-size:11px;font-weight:400;color:var(--muted)}.chart-panel[open]>summary>span{display:none}.chart-content{padding:0 22px 15px}.chart-content .small{margin:0 0 10px}#chart{display:block;width:100%;max-width:800px;margin:0 auto;height:auto}.guide{margin:14px 0 0;border:1px solid var(--line);border-radius:9px;background:#f9f8f3}.guide>summary{padding:15px 20px;color:var(--muted)}.notes{display:grid;grid-template-columns:1fr 1.6fr;gap:36px;padding:0 20px 20px;color:var(--muted);font-size:12px}.notes h2{color:var(--ink);margin-top:12px}.notes details{border-top:1px solid var(--line);padding-top:12px;margin-top:16px}.notes a{text-decoration:underline}.notes summary{color:var(--ink)}footer{display:flex;justify-content:space-between;gap:18px;padding:20px 0;color:var(--muted);font-size:11px}.skip{position:fixed;left:10px;top:-100px;padding:10px;background:white;z-index:10}.skip:focus{top:10px}:focus-visible{outline:2px solid #a94e2c;outline-offset:3px}.noscript{padding:24px;background:#fff0e8}
@media(max-width:1100px){header,main,footer{width:calc(100% - 36px)}.workbench{grid-template-columns:260px minmax(0,1fr)}.design{padding:18px}.metrics{grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.metric:nth-child(4){padding-left:0;border-left:0}.metric-unit{display:inline;margin-left:4px}.metric-value{font-size:20px}.metric-help{font-size:10px}}
@media(max-width:700px){header,main,footer{width:calc(100% - 24px)}.site-header{height:50px}.workspace-header{padding:16px;align-items:start;gap:10px}h1{font-size:20px}.workspace-header p{font-size:11px}.workspace-header .button{font-size:11px;padding:7px 9px}.workbench{display:flex;flex-direction:column}.output{display:contents}.viewer{order:0}.performance{order:1;padding:16px}.design{order:2;border-right:0;border-top:1px solid var(--line);padding:18px 16px}.chart-panel{order:3}.design>h2{margin-bottom:16px}#inputs{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 18px}.control-top{flex-wrap:wrap;gap:5px}.control{min-width:0}.core{margin-top:5px}.core-options{max-width:320px}#viewport{height:245px}.viewer-heading{padding:14px 16px 0}.viewer-controls{margin:0 16px}.scene-labels{padding:0 16px 8px}.buttons button{min-height:36px;min-width:31px;padding:6px 7px}.toggles{gap:14px}.viewer-hint{font-size:9px}.metrics{gap:15px 8px}.metric{padding-left:8px}.metric-label{font-size:10px}.metric-value{font-size:19px}.metric-unit{display:block;margin:2px 0 0}.metric-help{font-size:9px}.section-label>span{font-size:10px}.chart-panel>summary{padding:15px 16px}.chart-panel>summary>span{display:none}.chart-content{padding:0 12px 12px}.notes{grid-template-columns:1fr;gap:6px;padding:0 16px 16px}.guide>summary{padding:14px 16px;font-size:11px}.experiment-buttons{grid-template-columns:repeat(2,minmax(0,1fr))}.experiment-buttons button{font-size:11px}.brand{font-size:18px}footer{font-size:10px;flex-wrap:wrap}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}