:root {
  --bg: #e8edf1;
  --panel: rgba(255, 255, 255, 0.92);
  --ink: #1f2328;
  --muted: #5b636d;
  --line: #d9dee3;
  --accent: #2f6f8f;
  --accent-ink: #ffffff;
  --radius: 10px;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
}

#viewport { position: fixed; inset: 0; }
#viewport canvas { display: block; }

.panel {
  position: fixed;
  top: 16px;
  left: 16px;
  width: 290px;
  max-height: calc(100% - 32px);
  overflow-y: auto;
  background: var(--panel);
  backdrop-filter: blur(8px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 6px 24px rgba(20, 30, 40, 0.12);
  padding: 16px 16px 12px;
  z-index: 10;
}

.panel header h1 { font-size: 18px; margin: 0 0 4px; letter-spacing: 0.01em; }
.panel .sub { margin: 0; font-size: 12.5px; color: var(--muted); line-height: 1.4; }
.panel section { margin-top: 16px; }
.panel h2 {
  font-size: 11px; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted);
  margin: 0 0 8px; font-weight: 600;
}

.seg { display: flex; gap: 4px; flex-wrap: wrap; }
.seg.vertical { flex-direction: column; }
.seg button {
  font: inherit; font-size: 13px;
  border: 1px solid var(--line); background: #fff; color: var(--ink);
  padding: 7px 10px; border-radius: 7px; cursor: pointer; text-align: left;
  transition: background 0.15s, border-color 0.15s;
}
.seg:not(.vertical) button { flex: 1; text-align: center; }
.seg button:hover { border-color: #b8c2cb; background: #f6f8fa; }
.seg button.active { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.seg button .meta { float: right; opacity: 0.7; font-size: 11.5px; margin-top: 1px; }
.seg button .short { display: none; }
.seg button:focus-visible, .tog input:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.tog { display: flex; align-items: center; gap: 8px; font-size: 13px; padding: 3px 0; cursor: pointer; }
.tog input { accent-color: var(--accent); width: 15px; height: 15px; margin: 0; }
.hint-small { font-size: 11.5px; color: var(--muted); margin: 6px 0 0; }

.info { font-size: 12.5px; line-height: 1.45; }
.info h3 { margin: 0 0 4px; font-size: 14px; }
.info p { margin: 0 0 6px; color: #333a42; }
.info ul { margin: 6px 0 0; padding: 0; list-style: none; columns: 2; column-gap: 10px; }
.info li { break-inside: avoid; margin-bottom: 4px; }
.info li .d { display: block; color: var(--muted); font-size: 11px; }
.info .stat { display: flex; gap: 12px; margin: 6px 0; flex-wrap: wrap; }
.info .stat div { background: #f2f5f7; border-radius: 6px; padding: 5px 8px; }
.info .stat b { display: block; font-size: 13px; }
.info .stat span { font-size: 11px; color: var(--muted); }

.notes { margin-top: 14px; font-size: 12px; color: var(--muted); border-top: 1px solid var(--line); padding-top: 10px; }
.notes summary { cursor: pointer; color: var(--ink); font-weight: 600; font-size: 12.5px; }
.notes p { line-height: 1.45; margin: 8px 0 0; }
.notes code { font-size: 11px; }

.hud {
  position: fixed; bottom: 14px; left: 50%; transform: translateX(-50%);
  background: rgba(31, 35, 40, 0.72); color: #fff; font-size: 12px;
  padding: 6px 12px; border-radius: 999px; pointer-events: none; white-space: nowrap; z-index: 5;
}
.hud.walk { background: rgba(31, 35, 40, 0.85); }
kbd {
  display: inline-block; font: 11px ui-monospace, SFMono-Regular, Menlo, monospace;
  background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.3);
  border-radius: 4px; padding: 0 4px; margin: 0 1px;
}

.overlay-msg {
  position: fixed; inset: 0; display: grid; place-items: center; z-index: 20;
  background: rgba(20, 26, 32, 0.45);
}
.overlay-msg[hidden] { display: none; }
.overlay-msg > div {
  background: #fff; padding: 22px 24px; border-radius: 12px; text-align: center; max-width: 340px;
  box-shadow: 0 10px 40px rgba(0,0,0,0.25);
}
.overlay-msg h3 { margin: 0 0 6px; }
.overlay-msg p { margin: 0 0 14px; color: var(--muted); font-size: 13px; }
.overlay-msg button {
  font: inherit; font-size: 13px; padding: 8px 14px; border-radius: 7px; border: 1px solid var(--line);
  background: #fff; cursor: pointer; margin: 0 3px;
}
.overlay-msg button.primary { background: var(--accent); color: #fff; border-color: var(--accent); }

/* CSS2D labels */
.room-label {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: 5px;
  padding: 2px 7px 3px;
  text-align: center;
  pointer-events: none;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.12);
  white-space: nowrap;
  line-height: 1.2;
}
.room-label .n { display: block; font-size: 11px; font-weight: 650; text-transform: uppercase; letter-spacing: 0.04em; color: #1f2328; }
.room-label .d { display: block; font-size: 10.5px; color: #4b535c; font-variant-numeric: tabular-nums; }
.room-label.inferred { background: rgba(255, 255, 255, 0.72); }
.room-label.inferred .n { font-style: italic; font-weight: 500; text-transform: none; letter-spacing: 0; color: #4b535c; }

.north-label {
  font: 700 14px system-ui, sans-serif; color: #2b2f36;
  background: rgba(255,255,255,0.85); border-radius: 50%; width: 22px; height: 22px;
  display: grid; place-items: center; pointer-events: none;
}

.panel-toggle {
  display: none; position: fixed; top: 12px; left: 12px; z-index: 11;
  width: 40px; height: 40px; border-radius: 10px; border: 1px solid var(--line);
  background: var(--panel); font-size: 18px; cursor: pointer;
}

@media (max-width: 720px) {
  .panel-toggle { display: block; }
  .panel {
    top: auto; bottom: 0; left: 0; right: 0; width: auto;
    max-height: 52%; border-radius: 14px 14px 0 0; padding: 14px 16px;
  }
  .panel.collapsed { display: none; }
  .seg.vertical { flex-direction: row; flex-wrap: wrap; }
  .seg.vertical button { flex: 1 1 30%; text-align: center; }
  .seg button .meta, .seg button .long { display: none; }
  .seg button .short { display: inline; }
  .seg.vertical button { flex: 1 1 22%; padding: 7px 4px; }
  .hud { display: none; }
  #walk-btn { display: none; }
}