/* ─── Design Tokens ─── */
:root {
  --bg: #080c14;
  --bg-panel: rgba(12, 18, 32, 0.85);
  --text: #e2e8f0;
  --text-muted: #8b97b0;
  --accent: #64d2ff;
  --accent-dim: rgba(100, 210, 255, 0.18);
  --accent-hot: #ff6b9d;
  --accent-green: #64ffda;
  --accent-warn: #ffaa32;
  --border: rgba(100, 210, 255, 0.12);
  --radius: 12px;
  --blur: 18px;
}

/* ─── Reset ─── */
*, *::before, *::after { box-sizing: border-box; }
html { color-scheme: dark; }

body {
  margin: 0;
  height: 100vh;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
}

canvas { display: block; width: 100vw; height: 100vh; }

/* ─── Loading ─── */
.loading-overlay {
  position: fixed; inset: 0; z-index: 100;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 16px;
  background: var(--bg); color: var(--accent);
  font-size: 14px; letter-spacing: 0.04em;
  transition: opacity 0.6s ease;
}
.loading-overlay.hidden { opacity: 0; pointer-events: none; }
.loading-spinner {
  width: 36px; height: 36px;
  border: 3px solid var(--border); border-top-color: var(--accent);
  border-radius: 50%; animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ─── Panels ─── */
.panel {
  position: fixed;
  background: var(--bg-panel);
  -webkit-backdrop-filter: blur(var(--blur));
  backdrop-filter: blur(var(--blur));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  z-index: 10;
  color: var(--text);
  transition: opacity 0.3s ease;
}
.panel h2, .panel h3 {
  margin: 0 0 10px;
  font-size: 14px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--accent);
}

/* ─── Info Panel ─── */
#info-panel { top: 20px; left: 20px; max-width: 320px; min-width: 220px; }

.info-row {
  display: flex; justify-content: space-between;
  padding: 3px 0; font-size: 13px;
}
.info-row .label { color: var(--text-muted); }

.info-desc {
  margin: 10px 0 0; font-size: 11.5px;
  line-height: 1.55; color: var(--text-muted); max-width: 280px;
}

.state-badge {
  padding: 1px 8px; border-radius: 6px;
  font-size: 11px; font-weight: 600;
  background: rgba(100, 210, 255, 0.15); color: var(--accent);
}
.state-badge.bound {
  background: rgba(100, 255, 218, 0.15); color: var(--accent-green);
}
.state-badge.active {
  background: rgba(255, 107, 157, 0.15); color: var(--accent-hot);
}

#info-panel select {
  background: rgba(255,255,255,0.06); color: var(--text);
  border: 1px solid var(--border); border-radius: 6px;
  padding: 3px 6px; font-size: 12px; outline: none; max-width: 170px;
}

/* ─── Controls ─── */
#controls-panel { bottom: 20px; left: 20px; min-width: 220px; }

.control-row {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 8px; font-size: 13px;
}
.control-row label { color: var(--text-muted); flex-shrink: 0; margin-right: 12px; }
.control-row input[type="range"] { flex: 1; accent-color: var(--accent); max-width: 110px; }
.control-row input[type="checkbox"] { accent-color: var(--accent); width: 16px; height: 16px; }

.btn-row { display: flex; gap: 8px; margin-top: 8px; }

.btn-action {
  flex: 1; padding: 7px 0;
  background: var(--accent-dim); color: var(--accent);
  border: 1px solid var(--border); border-radius: 8px;
  font-size: 12px; font-weight: 600; cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}
.btn-action:hover { background: rgba(100, 210, 255, 0.28); }
.btn-action:active { transform: scale(0.97); }
.btn-accent { background: rgba(255, 107, 157, 0.15); color: var(--accent-hot); border-color: rgba(255, 107, 157, 0.2); }
.btn-accent:hover { background: rgba(255, 107, 157, 0.28); }
.btn-info { background: rgba(100, 255, 218, 0.12); color: var(--accent-green); border-color: rgba(100, 255, 218, 0.2); }
.btn-info:hover { background: rgba(100, 255, 218, 0.25); }

/* ─── Legend ─── */
#legend { top: 20px; right: 20px; min-width: 175px; }

.legend-row {
  display: flex; align-items: center; gap: 8px;
  font-size: 12px; padding: 2px 0; color: var(--text-muted);
}
.legend-divider { height: 1px; background: var(--border); margin: 10px 0; }

.legend-mol {
  display: flex; align-items: center; gap: 8px;
  font-size: 12px; padding: 3px 0;
}
.legend-dot {
  width: 10px; height: 10px; border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.15); flex-shrink: 0;
}

kbd {
  display: inline-block; min-width: 22px; padding: 1px 5px;
  background: rgba(255,255,255,0.07); border: 1px solid rgba(255,255,255,0.12);
  border-radius: 4px; font-family: inherit; font-size: 11px;
  text-align: center; color: var(--accent);
}

/* ─── Tooltip ─── */
.tooltip {
  position: fixed; background: var(--bg-panel);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px); border: 1px solid var(--border);
  border-radius: 8px; padding: 6px 12px; font-size: 12px;
  color: var(--text); pointer-events: none; z-index: 20; white-space: nowrap;
}

.is-hidden { display: none; }

/* ─── FPS ─── */
.fps-badge {
  position: fixed; bottom: 20px; right: 20px;
  background: var(--bg-panel);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border); border-radius: 8px;
  padding: 4px 12px; font-size: 11px; font-weight: 600;
  color: var(--accent); z-index: 10; font-variant-numeric: tabular-nums;
}

/* ─── Toast ─── */
.toast {
  position: fixed; bottom: 80px; left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--bg-panel);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border: 1px solid var(--border); border-radius: 10px;
  padding: 10px 24px; font-size: 13px; color: var(--text);
  z-index: 30; opacity: 0; pointer-events: none;
  transition: opacity 0.35s ease, transform 0.35s ease;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

.home-link-wrap {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 12;
}

.home-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.65rem 0.95rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(8, 12, 20, 0.74);
  color: var(--text);
  text-decoration: none;
  font-size: 12px;
  font-weight: 700;
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
}

.home-link:hover,
.home-link:focus-visible {
  border-color: rgba(100, 210, 255, 0.32);
  color: var(--accent);
}

/* ─── Responsive ─── */
@media (max-width: 600px) {
  .panel { padding: 10px 14px; }
  #info-panel { top: 10px; left: 10px; right: 10px; min-width: auto; }
  #controls-panel { bottom: 10px; left: 10px; right: 10px; min-width: auto; }
  #legend { display: none; }
}