:root { color-scheme: light; --paper: #efece4; --ink: #1c1b19; --muted: #6c6860; --card: rgba(255,255,255,0.86); }
html, body { margin: 0; height: 100%; background: var(--paper); color: var(--ink);
  font: 14px/1.4 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; overflow: hidden; }
#sumi { position: fixed; inset: 0; width: 100vw; height: 100vh; display: block; touch-action: none; }
#chrome { position: fixed; inset: 0; pointer-events: none; }
#chrome > * { pointer-events: auto; }
#status { position: absolute; top: 12px; left: 12px; padding: 4px 10px; border-radius: 6px; background: var(--card); }
#status:empty { display: none; }
.muted { color: var(--muted); }
button { font: inherit; padding: 4px 10px; border: 1px solid #b9b4a8; border-radius: 6px; background: #faf8f3; color: var(--ink); cursor: pointer; }
button:disabled { opacity: 0.5; cursor: default; }
.card { background: var(--card); border: 1px solid #d8d3c8; border-radius: 10px; padding: 10px 12px; box-shadow: 0 2px 10px rgba(0,0,0,0.06); }
#hint { position: absolute; left: 12px; right: 12px; bottom: 12px; max-width: 720px; margin: 0 auto; }
#hint button { margin-left: 8px; }
#scene-panel { position: absolute; right: 12px; top: 12px; width: min(360px, calc(100vw - 24px)); }
.scene-head { display: flex; align-items: center; justify-content: space-between; font-weight: 600; }
.formula { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 12.5px; margin: 6px 0 8px; color: #333; white-space: pre-wrap; }
.slider { display: grid; grid-template-columns: 2.2em 1fr 3.6em; gap: 8px; align-items: center; margin: 4px 0; }
.slider .sym { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
.slider .val { text-align: right; font-variant-numeric: tabular-nums; color: var(--muted); }
.overlay { position: fixed; inset: 0; display: grid; place-items: center; background: rgba(239,236,228,0.9); }
/* An author `display` beats the UA's [hidden]{display:none} — restate it, or the
   "no WebGPU" card paints over a working canvas (found by the user). */
.overlay[hidden] { display: none; }
body.embed #status, body.embed #hint { display: none; }
body.embed #scene-panel { top: 8px; right: 8px; }
/* lil-gui: the settings panel (the desktop app's settings window, in the browser) sits
   top-left — its title is the brand, there is no top bar. lil-gui 0.21 class names are
   lil-root / lil-title / lil-auto-place, and its own `.lil-gui.lil-auto-place { top: 0;
   right: 15px }` is injected AFTER this sheet — the third class here outranks it. */
.lil-gui.lil-root.lil-auto-place { position: fixed; top: 12px; left: 12px; right: auto; --width: 300px; --font-size: 12px;
  z-index: 5; max-height: calc(100vh - 24px); overflow-y: auto; }
.lil-gui.lil-root > .lil-title { background: #2b2925; }
@media (min-width: 720px) { #hint { left: 330px; right: 12px; margin: 0; } }   /* keep the hint clear of the panel */