:root {
  color-scheme: dark;
  --bg: #05070d;
  --bg-glow: #0d1a33;
  --panel: rgba(12, 17, 30, 0.8);
  --panel-border: rgba(255, 255, 255, 0.12);
  --text: #eef2f8;
  --text-muted: #a6b0c3;
  --accent: #3d8bff;
  --accent-strong: #1f6fff;
  --accent-text: #ffffff;
  --chip-active: #ffffff;
  --chip-active-text: #0a1020;
  --focus: #ffd24d;
  --radius: 14px;
  --tap: 44px;
  --gutter: 16px;
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
  --safe-left: env(safe-area-inset-left, 0px);
  --safe-right: env(safe-area-inset-right, 0px);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: radial-gradient(ellipse at 50% 40%, var(--bg-glow) 0%, var(--bg) 70%);
  color: var(--text);
  -webkit-tap-highlight-color: transparent;
}

/* In WebXR the camera feed must show through. */
body.in-ar, body.in-ar #overlay { background: transparent; }

#stage, #stage canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  touch-action: none;
}

#overlay {
  position: fixed;
  inset: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: calc(12px + var(--safe-top)) calc(var(--gutter) + var(--safe-right))
           calc(12px + var(--safe-bottom)) calc(var(--gutter) + var(--safe-left));
  pointer-events: none; /* only real controls capture input; drags reach the 3D canvas */
}

#overlay button, #overlay details, #overlay a, #overlay label, #overlay .legend-bar, #overlay .chips { pointer-events: auto; }

.panel {
  background: var(--panel);
  border: 1px solid var(--panel-border);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

/* ---------------------------------------------------------------- top */

.top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.brand h1 { margin: 0; font-size: 1.3rem; font-weight: 700; }
.brand p { margin: 2px 0 0; font-size: 0.88rem; color: var(--text-muted); }

.pill {
  min-height: var(--tap);
  padding: 0 18px;
  border-radius: 999px;
  border: 1px solid transparent;
  background: var(--accent-strong);
  color: var(--accent-text);
  font: inherit;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  box-shadow: 0 6px 20px rgba(31, 111, 255, 0.35);
}

.pill.is-3d { background: var(--panel); border-color: var(--panel-border); box-shadow: none; }

.tabs {
  align-self: center;
  display: grid;
  grid-template-columns: 1fr 1fr;
  width: min(100%, 320px);
  padding: 4px;
  border-radius: 999px;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  pointer-events: auto;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.tabs button {
  min-height: 38px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--text);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.tabs button[aria-selected="true"] { background: var(--chip-active); color: var(--chip-active-text); }

.status {
  align-self: center;
  margin: 0;
  padding: 8px 14px;
  border-radius: 999px;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  font-size: 0.88rem;
  text-align: center;
  max-width: min(92vw, 440px);
}

.status:empty { display: none; }

/* ---------------------------------------------------------------- bottom */

.bottom {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: center;
  width: 100%;
}

.bottom > * { width: 100%; max-width: 620px; }

.chips {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  padding: 2px 2px 4px;
  scrollbar-width: none;
}

.chips::-webkit-scrollbar { display: none; }

.chip {
  flex: 0 0 auto;
  scroll-snap-align: center;
  min-height: var(--tap);
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid var(--panel-border);
  background: var(--panel);
  color: var(--text);
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: background-color 0.3s ease, color 0.3s ease;
}

.chip[aria-checked="true"] { background: var(--chip-active); color: var(--chip-active-text); }
.chip:disabled { opacity: 0.5; cursor: progress; }

.switch {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: var(--tap);
  margin-top: 6px;
  padding: 0 14px;
  border-radius: 999px;
  width: auto !important;
  align-self: center;
  background: var(--panel);
  border: 1px solid var(--panel-border);
  font-weight: 600;
  cursor: pointer;
}

.switch[hidden] { display: none; }
.switch input { width: 20px; height: 20px; accent-color: var(--accent); }

.legend-bar {
  padding: 10px 12px 8px;
  border-radius: var(--radius);
  background: var(--panel);
  border: 1px solid var(--panel-border);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  animation: fade-in 0.4s ease;
}

.legend-unit { margin: 0 0 6px; font-size: 0.78rem; color: var(--text-muted); }
.ramp { height: 12px; border-radius: 6px; }

.ticks {
  position: relative;
  height: 16px;
  margin-top: 3px;
  font-size: 0.75rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}

.ticks span { position: absolute; transform: translateX(-50%); white-space: nowrap; }
.ticks span:first-child { transform: none; }
.ticks span:last-child { transform: translateX(-100%); }

.classes {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 12px;
  margin: 0 0 8px;
  padding: 0;
  list-style: none;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.classes li { display: inline-flex; align-items: center; gap: 5px; }

.swatch {
  display: inline-block;
  width: 11px;
  height: 11px;
  border-radius: 3px;
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.info {
  border-radius: var(--radius);
  background: var(--panel);
  border: 1px solid var(--panel-border);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.info summary {
  min-height: var(--tap);
  display: flex;
  align-items: center;
  padding: 0 16px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

.info summary::-webkit-details-marker { display: none; }
.info summary::after { content: "+"; margin-left: auto; font-size: 1.3rem; color: var(--text-muted); }
.info[open] summary::after { content: "−"; }

.info-body {
  max-height: 40vh;
  overflow-y: auto;
  padding: 0 16px 14px;
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--text-muted);
}

.info-body h3 { margin: 6px 0 4px; font-size: 0.95rem; color: var(--text); }
.info-body p { margin: 0 0 8px; }
.info-body strong { color: var(--text); }

.facts { display: grid; grid-template-columns: auto 1fr; gap: 4px 12px; margin: 0 0 10px; }
.facts dt { color: var(--text); font-weight: 600; }
.facts dd { margin: 0; }

.credits { margin: 0; padding-left: 18px; font-size: 0.82rem; }
.credits li { margin-bottom: 6px; }

.btn-inline {
  min-height: 40px;
  margin: 2px 8px 10px 0;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid var(--panel-border);
  background: var(--accent-strong);
  color: var(--accent-text);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

.info-body a { color: var(--text); }

.attribution {
  margin: 0;
  font-size: 0.7rem;
  line-height: 1.4;
  color: var(--text-muted);
  text-align: center;
}

/* ---------------------------------------------------------------- start screen */

.start {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: grid;
  place-items: end center;
  padding: 24px calc(var(--gutter) + var(--safe-right)) calc(28px + var(--safe-bottom)) calc(var(--gutter) + var(--safe-left));
  background: linear-gradient(180deg, rgba(5, 7, 13, 0) 0%, rgba(5, 7, 13, 0.55) 45%, rgba(5, 7, 13, 0.92) 100%);
}

.start[hidden] { display: none; }

.start-card { width: min(100%, 460px); text-align: center; }
.start-kicker { margin: 0 0 6px; font-size: 0.8rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--text-muted); }
.start-card h2 { margin: 0 0 8px; font-size: 1.55rem; line-height: 1.2; }
.start-card p { margin: 0 0 18px; color: var(--text-muted); }

.btn-primary {
  width: 100%;
  min-height: 56px;
  border: 0;
  border-radius: 999px;
  background: var(--accent-strong);
  color: var(--accent-text);
  font: inherit;
  font-size: 1.1rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 8px 28px rgba(31, 111, 255, 0.45);
}

.btn-link {
  margin-top: 10px;
  min-height: var(--tap);
  padding: 0 16px;
  border: 0;
  background: transparent;
  color: var(--text);
  font: inherit;
  text-decoration: underline;
  cursor: pointer;
}

.start-hint { margin: 8px 0 0 !important; font-size: 0.8rem; }

button:focus-visible, summary:focus-visible, a:focus-visible, input:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.noscript { position: fixed; inset: 40% 16px auto; text-align: center; }

/* In AR keep the screen as clear as possible. */
body.in-ar .attribution { display: none; }
body.in-ar .info-body { max-height: 28vh; }

@keyframes fade-in { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

@media (min-width: 720px) {
  .brand h1 { font-size: 1.55rem; }
  .chips { justify-content: center; flex-wrap: wrap; overflow: visible; }
}

@media (prefers-reduced-motion: reduce) {
  .chip, .tabs button, .legend-bar { transition: none; animation: none; }
}