:root{--bg: #1e1f22;--panel: #26282c;--raised: #31343a;--border: #3c4047;--text: #e9e9eb;--muted: #a3a7ad;--accent: #e2a458;--accent-text: #1e1f22;--selected: #464a52;--selected-ring: #d6d8dc;--control: #c4c7cc;--focus-ring: #8ab4f8;--worth: #e8c468;--danger: #e5675c;--canvas-bg: #7f7f7f;--plane-fg: #ff8a3d;--plane-mg: #4caf50;--plane-bg: #3d7bff;--plane-erase: #ffffff;--radius: 8px;--tap: 44px;color-scheme:dark}*{box-sizing:border-box}html,body{margin:0;height:100%;background:var(--bg);color:var(--text);font:15px/1.4 system-ui,-apple-system,Segoe UI,Roboto,sans-serif;-webkit-text-size-adjust:100%;overscroll-behavior:none}.app{position:fixed;inset:0;display:flex;flex-direction:column;padding:env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left)}button,.button{min-height:var(--tap);padding:0 14px;border:1px solid var(--border);border-radius:var(--radius);background:var(--raised);color:var(--text);font:inherit;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;gap:8px;-webkit-tap-highlight-color:transparent;user-select:none;-webkit-user-select:none}button:disabled{opacity:.45;cursor:default}button.active,.segmented button.active{background:var(--selected);border-color:var(--selected-ring);box-shadow:inset 0 0 0 1px var(--selected-ring)}.views button.active{background:var(--accent);border-color:var(--accent);color:var(--accent-text);box-shadow:none;font-weight:600}.button.primary{background:var(--accent);border-color:var(--accent);color:var(--accent-text);font-weight:600}.file-button input{display:none}button:focus-visible,.button:focus-within,input:focus-visible,select:focus-visible,summary:focus-visible{outline:2px solid var(--focus-ring);outline-offset:2px}.key{display:none}@media(pointer:fine){.key{display:inline-block;min-width:18px;padding:0 4px;border:1px solid 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canvas{position:absolute;left:0;top:0;width:100%;height:100%;display:block}.empty{flex:1;display:flex;flex-direction:column;justify-content:center;padding:24px max(16px,8vw);background:var(--canvas-bg);color:#111}.empty h1{margin:0 0 12px;font-size:26px}.empty ol{margin:0;padding-left:22px;font-size:17px}.empty li{margin:6px 0}.busy,.error{position:absolute;left:50%;top:16px;transform:translate(-50%);padding:10px 16px;border-radius:var(--radius);background:#141416e0;color:var(--text);box-shadow:0 4px 16px #00000059;max-width:calc(100% - 32px)}.error{display:flex;align-items:center;gap:12px;border:1px solid var(--danger)}.panel{width:clamp(320px,24vw,440px);flex-shrink:0;overflow-y:auto;-webkit-overflow-scrolling:touch;border-left:1px solid var(--border);background:var(--panel)}.panel-inner{padding:4px 14px 24px}.panel section{padding:12px 0;border-bottom:1px solid var(--border)}.panel section:last-child{border-bottom:0}.panel h2{margin:0 0 10px;font-size:12px;font-weight:600;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}.panel section>*+*{margin-top:10px}.tool-grid{display:grid;grid-template-columns:1fr 1fr;gap:6px}.tool{justify-content:flex-start;padding:0 10px}.focal-tool{width:100%}.ring{width:14px;height:14px;border-radius:50%;border:2px solid currentColor;box-shadow:0 0 0 2px #00000040;flex-shrink:0}.swatch{width:14px;height:14px;border-radius:50%;border:1px solid rgba(0,0,0,.4);flex-shrink:0}.segmented{display:flex}.segmented button{flex:1;border-radius:0}.segmented button:first-child{border-radius:var(--radius) 0 0 var(--radius)}.segmented button:last-child{border-radius:0 var(--radius) var(--radius) 0;border-left:0}.row{display:flex;gap:6px;flex-wrap:wrap}.row button{flex:1;padding:0 8px;white-space:nowrap}.slider{display:block}.slider-label{display:flex;justify-content:space-between;color:var(--text)}.slider-label output{color:var(--muted);font-variant-numeric:tabular-nums}.slider input{width:100%;height:var(--tap);margin:0;accent-color:var(--control)}.toggle{display:flex;align-items:center;gap:10px;min-height:36px}.toggle input{width:20px;height:20px;accent-color:var(--control)}.select{display:flex;align-items:center;justify-content:space-between;gap:10px}.select select{min-height:var(--tap);padding:0 10px;border-radius:var(--radius);border:1px solid var(--border);background:var(--raised);color:var(--text);font:inherit}.hint{margin:0;color:var(--muted);font-size:14px}.look-for{margin:0;font-size:15px;line-height:1.45}@media(max-width:860px),(orientation:portrait)and (max-width:1100px){.workspace{flex-direction:column}.panel{width:auto;max-height:42%;border-left:0;border-top:1px solid var(--border)}.panel-inner{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));column-gap:20px}.panel section:last-child{border-bottom:1px solid var(--border)}}.why-cards{display:grid;gap:10px}.why-card{background:var(--raised);border:1px solid var(--border);border-radius:var(--radius);padding:12px 14px}.why-card.worth{border-left:3px solid var(--worth)}.why-card .badge{margin:0 0 4px;color:var(--worth);font-size:12px;font-weight:600;text-transform:uppercase;letter-spacing:.06em}.why-card h3{margin:0;font-size:16px;font-weight:600}.why-card .card-head{display:flex;align-items:flex-start;justify-content:space-between;gap:10px;margin-bottom:6px}.why-card .card-head h3{padding-top:4px}.why-card .show{flex-shrink:0;min-height:30px;padding:0 10px;gap:6px;font-size:14px;color:var(--muted)}.why-card .show[aria-pressed=true]{color:var(--text);background:var(--selected);border-color:var(--selected-ring);box-shadow:inset 0 0 0 1px var(--selected-ring)}.why-card.lit{border-color:var(--selected-ring)}.why-card .card-controls{margin-top:10px;padding-top:8px;border-top:1px solid var(--border);display:grid;gap:6px}.why-card .control-group{display:grid;gap:6px}.why-card .card-controls .focal-tool{width:100%}.why-card 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input{width:16px;height:16px}}.value-scale{display:flex;gap:4px}.value-step{flex:1;display:flex;flex-direction:column;align-items:center;gap:2px;min-width:0}.value-step .chip{width:100%;height:34px;border-radius:6px;border:1px solid rgba(0,0,0,.35);display:flex;align-items:center;justify-content:center;font-weight:600}button.chip{min-height:0;padding:0}@media(pointer:coarse){.value-scale button.chip,.why-card .show{min-height:var(--tap);height:var(--tap)}}button.chip[aria-pressed=true]{outline:2px solid var(--selected-ring);outline-offset:2px}@media(hover:hover)and (pointer:fine){button.chip:hover{outline:2px solid var(--muted);outline-offset:2px}button.chip[aria-pressed=true]:hover{outline-color:var(--selected-ring)}}.value-step .share,.swatch-meta{font-size:12px;color:var(--muted);font-variant-numeric:tabular-nums}.swatches{display:grid;grid-template-columns:repeat(4,1fr);gap:8px 6px}.swatch-item{display:flex;flex-direction:column;align-items:center;gap:3px}.swatch-item 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.swatches{grid-template-columns:repeat(8,1fr)}@media(max-width:600px){.lesson-sheet{padding:16px}.sheet-figures,.sheet-figures.portrait{grid-template-columns:1fr}.lesson-sheet .swatches{grid-template-columns:repeat(4,1fr)}}@media print{@page{margin:12mm}html,body{height:auto;overflow:visible;background:#fff}.app,.sheet-toolbar{display:none!important}.sheet-backdrop{position:static;overflow:visible;padding:0;background:none}.lesson-sheet{max-width:none;padding:0;border-radius:0}.sheet-figures{grid-template-columns:1fr 1fr}.sheet-figures.portrait{grid-template-columns:1fr 1fr 1fr}.lesson-sheet .swatches{grid-template-columns:repeat(8,1fr)}}