/* Chapter 05: demand-driven preview, ordinary page scrolling. */
.mix-overview{margin:0;border:1px solid var(--line);border-radius:13px;overflow:hidden;background:var(--surface)}
.mix-overview img{display:block;width:100%;height:auto}.mix-overview figcaption{display:grid;gap:8px;padding:20px 24px;color:var(--muted);font-size:14px;line-height:1.7}.mix-overview figcaption strong{color:var(--ink);font:600 20px/1.4 var(--display)}
.mix-lab-shell{border:1px solid var(--line);border-radius:14px;overflow:hidden;background:var(--surface)}
.mix-workbench{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(390px,1fr);align-items:start}
.mix-preview{min-width:0;background:#090f17}.mix-stage{position:relative;aspect-ratio:8/5;background:#090f17}
.mix-stage canvas,.mix-stage>img{display:block;width:100%;height:100%;object-fit:contain}
.mix-stage:has(>img:not([hidden]))>canvas{display:none}.mix-stage canvas{touch-action:pan-y pinch-zoom;cursor:crosshair}.mix-stage canvas:focus-visible{outline-offset:-3px}
.mix-stage [hidden]{display:none!important}.mix-legend{display:flex;flex-wrap:wrap;gap:10px 18px;padding:15px 20px;border-top:1px solid var(--line);font:400 10px/1.6 var(--mono);color:var(--muted)}
.mix-legend span{display:inline-flex;align-items:center;gap:8px}.mix-legend i{width:10px;height:10px;display:inline-block;border-radius:50%;flex:none}
.mix-a-color{background:#3366cc}.mix-b-color{background:#cc9933}.mix-p-color{border:2px solid #f5f5f5;background:#5973a6}
.mix-view-note,.mix-fallback-message{padding:0 20px;color:var(--dim);font-size:11px;line-height:1.7;margin:0 0 18px}.mix-fallback-message{color:var(--muted);padding-top:16px}
.mix-controls{min-width:0;padding:20px;border-left:1px solid var(--line)}
.mix-view-control{display:flex;align-items:center;gap:10px;flex-wrap:wrap}.mix-view-control>label{font:500 15px/1.5 var(--display)}
.mix-view-control select{flex:1;min-width:100px;max-width:100%;background:#0b111b;border:1px solid var(--line);border-radius:7px;color:var(--ink);padding:9px;font:400 11px/1.5 var(--mono)}
.mix-view-control button,.mix-preset-buttons button{border-radius:7px;padding:8px 10px;font-size:10px;min-height:36px}
.mix-shape-controls{padding-block:10px 14px;border-bottom:1px solid var(--line)}
.mix-shape-controls>p{color:var(--dim);font-size:10px;line-height:1.65;margin:12px 0 0}
.mix-input-row{display:grid;grid-template-columns:76px minmax(0,1fr) 84px;gap:8px;align-items:center;margin-top:9px}
.mix-input-row label{font:400 10px/1.5 var(--mono);color:var(--muted)}
.mix-input-row input[type=range]{min-width:0;width:100%;margin:0;min-height:30px;accent-color:#4ce0e3}
.mix-input-row input[type=number]{width:100%;min-width:0;border:1px solid var(--line);background:#0b111b;color:var(--ink);border-radius:6px;padding:7px 4px;font:400 11px/1.5 var(--mono);font-variant-numeric:tabular-nums}
.mix-point-controls{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px;margin-top:17px}
.mix-point-controls fieldset{min-width:0;padding:0;border:0;margin:0}.mix-point-controls legend{padding:0;color:var(--ink);font:500 15px/1.5 var(--display)}
.mix-point-controls .mix-input-row{grid-template-columns:10px minmax(0,1fr) 61px;gap:5px}.mix-point-controls fieldset:last-child input[type=range]{accent-color:#ffad59}
.mix-preset-buttons{display:flex;flex-wrap:wrap;gap:8px;margin-top:18px}
#mix-shader-status{font:400 10px/1.7 var(--mono);color:var(--accent);margin:15px 0 0;min-height:34px}
.mix-readouts{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:18px 20px;padding:22px;border-block:1px solid var(--line);margin:0;background:#0b111b}
.mix-readouts>div{min-width:0}.mix-readouts dt{color:var(--dim);font:400 10px/1.6 var(--mono);margin:0 0 6px}.mix-readouts dd{margin:0;color:var(--ink);font:400 14px/1.6 var(--mono);font-variant-numeric:tabular-nums;overflow-wrap:anywhere}
.mix-geometry-note{padding:14px 22px;margin:0;border-bottom:1px solid var(--line);min-height:69px;font-size:12px;line-height:1.7;color:var(--muted)}
.mix-readout-note,.mix-control-help{padding:0 22px;font-size:12px;line-height:1.75;color:var(--muted);margin:16px 0}.mix-readout-note{color:var(--dim);font-size:11px}
#mix-error{white-space:pre-wrap;overflow-wrap:anywhere;color:#ffb6a4;background:#291717;padding:16px;border-radius:8px;font-size:12px}.mix-lab-section .code-panel{min-width:0}
@media(max-width:900px){.mix-workbench{grid-template-columns:1fr}.mix-stage{max-width:800px;margin-inline:auto}.mix-controls{border-left:0;border-top:1px solid var(--line)}.mix-point-controls{gap:30px}.mix-input-row{grid-template-columns:85px minmax(0,1fr) 78px}.mix-point-controls .mix-input-row{grid-template-columns:14px minmax(0,1fr) 72px;gap:8px}.mix-preview{padding-bottom:1px}}
@media(max-width:580px){.mix-stage{aspect-ratio:1}.mix-controls{padding:18px}.mix-point-controls{grid-template-columns:1fr;gap:18px}.mix-input-row{grid-template-columns:73px minmax(0,1fr) 84px;gap:6px}.mix-point-controls .mix-input-row{grid-template-columns:14px minmax(0,1fr) 72px;gap:10px}.mix-readouts{grid-template-columns:repeat(2,minmax(0,1fr));gap:17px;padding:18px}.mix-legend{padding:14px 18px;gap:10px 18px}.mix-view-note,.mix-fallback-message,.mix-geometry-note,.mix-readout-note,.mix-control-help{padding-inline:18px}.mix-geometry-note{min-height:89px}}

.mix-heading-row{display:flex;justify-content:space-between;gap:12px;align-items:center}.mix-heading-row h3{margin:0;font:500 18px/1.5 var(--display)}
.mix-heading-row button,.mix-selection-buttons button,#mix-play{border-radius:7px;padding:8px 10px;font-size:10px;min-height:36px}
.mix-small-note{font-size:10px;line-height:1.7;color:var(--dim);margin:12px 0 0}.mix-timeline{border:0;border-block:1px solid var(--line);padding:16px 0;margin:19px 0 0;min-width:0}.mix-timeline legend{font:500 15px/1.5 var(--display);color:var(--ink);padding:0 8px 0 0}
.mix-timeline-mode-row{display:flex;gap:12px;align-items:center}.mix-timeline-mode-row label{font:400 10px/1.5 var(--mono);color:var(--muted)}.mix-timeline-mode-row select{flex:1;min-width:0;max-width:100%;background:#0b111b;border:1px solid var(--line);border-radius:7px;color:var(--ink);padding:9px;font:400 11px/1.5 var(--mono)}
#mix-play{margin-top:12px;color:var(--accent);border-color:var(--accent)}#mix-play:disabled{color:var(--dim);border-color:var(--line);cursor:default;opacity:.7}
.mix-selection-buttons{display:flex;align-items:center;flex-wrap:wrap;gap:7px;margin-top:17px}.mix-selection-buttons>span{font-size:10px;color:var(--muted)}.mix-selection-buttons [aria-pressed=true]{border-color:var(--accent);color:var(--accent)}
.mix-swatches{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;padding:0 20px 20px}.mix-swatches>div{min-width:0}.mix-swatches i{display:block;height:24px;border-radius:4px;margin-bottom:6px;border:1px solid #ffffff15}.mix-swatches span{font:400 9px/1.6 var(--mono);color:var(--muted)}
.mix-preview-toolbar{display:none;padding:12px 14px;gap:8px;align-items:center;flex-wrap:wrap;border-bottom:1px solid var(--line)}.mix-preview-toolbar label{font:400 10px/1.5 var(--mono);color:var(--muted)}.mix-preview-toolbar select{min-width:0;flex:1;background:#0b111b;border:1px solid var(--line);border-radius:7px;color:var(--ink);padding:8px;font:400 11px/1.5 var(--mono)}#mix-preview-play{border-radius:7px;padding:8px 10px;font-size:10px;min-height:36px;color:var(--accent);border-color:var(--accent)}#mix-preview-play:disabled{color:var(--dim);border-color:var(--line);cursor:default;opacity:.7}
@media(max-width:900px){.mix-readouts{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:900px){.mix-preview-toolbar{display:flex}}
@media(max-width:580px){.mix-swatches{padding:0 18px 18px;gap:10px}.mix-readouts dd{font-size:12px}}