/*
 * CALM — stylesheet
 *
 * Both themes are defined as tokens on :root, and the theme is chosen by the
 * data-theme attribute that ui.js sets from the system preference. Nothing
 * here depends on a build step.
 */

:root {
  --bg: #f4f4f5;
  --panel: #fff;
  --ink: #18181b;
  --muted: #71717a;
  --line: #e4e4e7;
  --accent: #2563eb;
  --track: #d4d4d8;
  color-scheme: light;
}

:root[data-theme="dark"] {
  --bg: #09090b;
  --panel: #18181b;
  --ink: #f4f4f5;
  --muted: #a1a1aa;
  --line: #27272a;
  --accent: #60a5fa;
  --track: #3f3f46;
  color-scheme: dark;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  display: flex;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font: 15px/1.55 system-ui, -apple-system, "Segoe UI", sans-serif;
}

/* ─── panel ───────────────────────────────────────────────────────────── */

#panel {
  flex: 0 0 22rem;
  padding: 1.25rem;
  background: var(--panel);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  max-height: 100vh;
}

#panel header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: .75rem;
  margin-bottom: 1.25rem;
}

h1 {
  margin: 0;
  font-size: 1.6rem;
  font-weight: 650;
  letter-spacing: .06em;
}

#subtitle {
  margin: .15rem 0 0;
  font-size: .8rem;
  color: var(--muted);
}

.switches {
  display: flex;
  align-items: center;
  gap: .35rem;
  flex-shrink: 0;
}

#langs, #dims { display: flex; gap: .25rem; }

h2 {
  margin: 1.5rem 0 .6rem;
  font-size: .72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--muted);
}

section > h2:first-child { margin-top: 0; }

/* ─── controls ────────────────────────────────────────────────────────── */

button, select {
  font: inherit;
  color: var(--ink);
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: .35rem;
  padding: .3rem .55rem;
  cursor: pointer;
}

button:hover, select:hover { border-color: var(--accent); }

/* Two primary actions side by side, the parameter reset on its own line
 * below: it is a secondary action, and giving it a third of the row would have
 * squeezed the two labels onto three lines each. */
.actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: .35rem;

  /* The first section heading below has its top margin cancelled, being the
   * first child of its section, so the breathing room has to come from here. */
  margin-bottom: 1.6rem;
}

.actions button {
  font-size: .85rem;
  line-height: 1.25;
}

#reset {
  grid-column: 1 / -1;
  color: var(--muted);
}

#reset:hover { color: var(--ink); }

#play.paused {
  border-color: var(--accent);
  color: var(--accent);
}

#langs button, #dims button, #theme {
  padding: .2rem .45rem;
  font-size: .75rem;
  line-height: 1.3;
}

#langs button.active, #dims button.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

label#model-label {
  display: block;
  margin-bottom: .4rem;
  font-size: .72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--muted);
}

#model-select { width: 100%; }

figure {
  margin: 1rem 0;
  text-align: center;
}

/* The illustrations have very different aspect ratios — the Vicsek one is a
 * wide strip, the Aoki-Reynolds-Couzin one is nearly square. A tight
 * max-height caps the near-square ones by their height, leaving them using
 * less than half the panel's width and far too small to read. Letting them
 * fill the width and giving the height a generous ceiling sizes each one by
 * whichever dimension actually binds. */
#illustration {
  width: 100%;
  height: auto;
  max-height: 15rem;
  object-fit: contain;
}

#description {
  margin: 0;
  font-size: .86rem;
  color: var(--muted);
}

/* ─── parameter rows ──────────────────────────────────────────────────── */

.param {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: baseline;
  gap: .1rem .5rem;
  margin-bottom: .85rem;
}

.param label {
  font-size: .85rem;
}

.param output {
  font-variant-numeric: tabular-nums;
  font-size: .8rem;
  color: var(--muted);
}

.param input[type="range"] {
  grid-column: 1 / -1;
  width: 100%;
  margin: .2rem 0 0;
  accent-color: var(--accent);
  background: transparent;
  cursor: grab;
}

.param input[type="range"]:active { cursor: grabbing; }

/* ─── stage ───────────────────────────────────────────────────────────── */

#stage {
  flex: 1;
  display: grid;
  place-items: center;
  padding: 1rem;
  min-width: 0;
}

/* The canvas is square and fits the shorter side of the stage. aspect-ratio
 * plus the two max-* rules keep it square without any measuring in script.
 *
 * Both views are styled identically and only one is ever shown: a canvas can
 * hold a 2D context or a WebGL one, not both, so the 3D view needs an element
 * of its own rather than a mode on the first. */
#view, #view3d {
  aspect-ratio: 1;
  width: 100%;
  height: auto;
  max-width: min(100%, calc(100vh - 2rem));
  max-height: 100%;
  border-radius: .3rem;
}

/* ─── narrow screens ──────────────────────────────────────────────────── */

@media (max-width: 48rem) {
  body { flex-direction: column-reverse; }

  #panel {
    flex: none;
    max-height: none;
    border-right: 0;
    border-top: 1px solid var(--line);
  }

  #stage { padding: .5rem; }

  #view, #view3d { max-width: min(100%, calc(100vh - 1rem)); }
}