/* Differentiable Digital Twin -- control-room player theme.
   Dark / OLED, blue data + amber material highlights, Fira Code / Fira Sans. */

:root {
  --bg: #05070d;
  --bg-grad: radial-gradient(1200px 800px at 70% -10%, #0c1530 0%, #05070d 60%);
  --panel: rgba(11, 16, 32, 0.82);
  --panel-solid: #0b1020;
  --border: #1b2742;
  --border-bright: #27406e;

  --primary: #3b82f6;
  --primary-deep: #1e40af;
  --accent: #f59e0b;
  --accent-deep: #d97706;
  --danger: #ef4444;
  --ok: #34d399;

  --text: #e7eefb;
  --text-dim: #9db0d4;
  --text-faint: #5f7299;

  --mono: "Fira Code", ui-monospace, "SF Mono", Menlo, monospace;
  --sans: "Fira Sans", system-ui, -apple-system, sans-serif;

  --r: 10px;
  --shadow: 0 10px 40px rgba(0, 0, 0, 0.55);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
}

#app {
  position: fixed;
  inset: 0;
  background: var(--bg-grad);
  display: grid;
  grid-template-rows: auto 1fr auto;
}

/* ---------------------------------------------------------------- header */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, rgba(8, 12, 24, 0.9), rgba(8, 12, 24, 0.3));
  backdrop-filter: blur(8px);
  z-index: 10;
}

.brand { display: flex; align-items: center; gap: 12px; min-width: 0; }
.brand .mark {
  width: 34px; height: 34px; flex: 0 0 auto;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--primary), var(--primary-deep));
  box-shadow: 0 0 18px rgba(59, 130, 246, 0.45);
  position: relative;
}
.brand .mark::after {
  content: ""; position: absolute; inset: 7px;
  border: 2px solid rgba(255, 255, 255, 0.85);
  border-right-color: var(--accent); border-bottom-color: var(--accent);
  border-radius: 50%;
}
.brand h1 {
  font-size: 14px; letter-spacing: 0.16em; margin: 0; font-weight: 600;
  text-transform: uppercase; white-space: nowrap;
}
.brand p {
  margin: 1px 0 0; font-size: 11px; color: var(--text-dim);
  font-family: var(--mono); white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}

.status { display: flex; align-items: center; gap: 10px; }
.badge {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.05em;
  padding: 5px 10px; border-radius: 999px;
  border: 1px solid var(--border-bright); color: var(--text-dim);
  display: inline-flex; align-items: center; gap: 7px; white-space: nowrap;
}
.badge .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--text-faint); }
.badge.live .dot { background: var(--ok); box-shadow: 0 0 8px var(--ok); animation: pulse 2s infinite; }
.badge.gpu .dot { background: var(--primary); box-shadow: 0 0 8px var(--primary); }
@keyframes pulse { 50% { opacity: 0.35; } }

/* ---------------------------------------------------------------- main */
main { position: relative; overflow: hidden; }
#scene { position: absolute; inset: 0; display: block; width: 100%; height: 100%; }

.overlay {
  position: absolute; top: 16px; left: 16px;
  width: 296px; max-width: calc(100vw - 32px);
  display: flex; flex-direction: column; gap: 12px;
  z-index: 5;
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--r);
  padding: 14px 15px;
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow);
}
.card h2 {
  font-size: 10px; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--text-faint); margin: 0 0 10px; font-weight: 600;
}

.headline { display: flex; align-items: baseline; gap: 8px; }
.headline .big {
  font-family: var(--mono); font-size: 40px; font-weight: 600; line-height: 1;
  color: var(--accent); text-shadow: 0 0 22px rgba(245, 158, 11, 0.35);
}
.headline .unit { font-family: var(--mono); font-size: 14px; color: var(--accent); }
.headline .lbl { font-size: 12px; color: var(--text-dim); margin-left: auto; text-align: right; }

.subnote {
  margin: 10px 0 0; font-family: var(--mono); font-size: 10px;
  letter-spacing: 0.04em; color: var(--text-faint);
}
.bars { margin-top: 12px; display: grid; gap: 8px; }
.bar-row { display: grid; grid-template-columns: 64px 1fr auto; align-items: center; gap: 8px; font-size: 11px; }
.bar-row .name { color: var(--text-dim); font-family: var(--mono); }
.bar-track { height: 8px; background: rgba(255, 255, 255, 0.05); border-radius: 4px; overflow: hidden; }
.bar-fill { height: 100%; border-radius: 4px; transition: width 0.4s ease; }
.bar-fill.uniform { background: linear-gradient(90deg, #475569, #64748b); }
.bar-fill.optimised { background: linear-gradient(90deg, var(--primary-deep), var(--primary)); }
.bar-row .val { font-family: var(--mono); color: var(--text); }

.kv { display: grid; grid-template-columns: 1fr auto; gap: 6px 10px; font-size: 12px; }
.kv .k { color: var(--text-dim); }
.kv .v { font-family: var(--mono); color: var(--text); text-align: right; }
.kv .v.accent { color: var(--accent); }
.kv .v.primary { color: var(--primary); }

.spark { width: 100%; height: 44px; display: block; margin-top: 4px; }

.legend { display: flex; align-items: center; gap: 8px; margin-top: 4px; font-size: 11px; color: var(--text-dim); }
.legend .ramp {
  flex: 1; height: 9px; border-radius: 4px;
  background: linear-gradient(90deg, #1f5fbf 0%, #3b82f6 40%, #c2791d 75%, var(--accent) 100%);
}

.control { margin-top: 12px; }
.control label {
  display: flex; justify-content: space-between; font-size: 11px;
  color: var(--text-dim); margin-bottom: 6px; font-family: var(--mono);
}
.control label b { color: var(--text); font-weight: 600; }

input[type="range"] {
  -webkit-appearance: none; appearance: none; width: 100%; height: 4px;
  background: var(--border-bright); border-radius: 4px; outline: none; cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; width: 16px; height: 16px; border-radius: 50%;
  background: var(--primary); border: 2px solid #cfe0ff; cursor: pointer;
  box-shadow: 0 0 10px rgba(59, 130, 246, 0.6);
}
input[type="range"]::-moz-range-thumb {
  width: 16px; height: 16px; border-radius: 50%; background: var(--primary);
  border: 2px solid #cfe0ff; cursor: pointer;
}

.toggles { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.toggle {
  font-family: var(--mono); font-size: 11px; cursor: pointer; user-select: none;
  padding: 6px 10px; border-radius: 7px; border: 1px solid var(--border);
  color: var(--text-dim); background: rgba(255, 255, 255, 0.02);
  transition: color 0.15s, border-color 0.15s, background 0.15s;
}
.toggle:hover { color: var(--text); border-color: var(--border-bright); }
.toggle[aria-pressed="true"] {
  color: #07101f; background: var(--primary); border-color: var(--primary);
  font-weight: 600;
}
.toggle:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------------------------------------------------------------- transport */
footer {
  display: flex; align-items: center; gap: 16px;
  padding: 12px 20px;
  border-top: 1px solid var(--border);
  background: linear-gradient(0deg, rgba(8, 12, 24, 0.92), rgba(8, 12, 24, 0.4));
  backdrop-filter: blur(8px);
  z-index: 10;
}
.transport-btn {
  width: 42px; height: 42px; flex: 0 0 auto; border-radius: 50%;
  border: 1px solid var(--border-bright); background: rgba(59, 130, 246, 0.12);
  color: var(--text); cursor: pointer; display: grid; place-items: center;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
}
.transport-btn:hover { background: rgba(59, 130, 246, 0.25); border-color: var(--primary); }
.transport-btn:active { transform: scale(0.94); }
.transport-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.transport-btn svg { width: 18px; height: 18px; fill: currentColor; }

.timeline { flex: 1; display: flex; align-items: center; gap: 12px; min-width: 0; }
.timeline input[type="range"] { flex: 1; }
.frame-readout {
  font-family: var(--mono); font-size: 12px; color: var(--text-dim);
  white-space: nowrap; min-width: 96px; text-align: right;
}
.frame-readout b { color: var(--text); }

.speed { display: flex; align-items: center; gap: 6px; }
.speed button {
  font-family: var(--mono); font-size: 11px; cursor: pointer;
  padding: 5px 9px; border-radius: 6px; border: 1px solid var(--border);
  background: transparent; color: var(--text-dim); transition: all 0.15s;
}
.speed button[aria-pressed="true"] { color: var(--text); border-color: var(--primary); background: rgba(59,130,246,0.15); }
.speed button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------------------------------------------------------------- loader / toast */
#loader {
  position: absolute; inset: 0; display: grid; place-items: center; z-index: 20;
  background: var(--bg); transition: opacity 0.5s; text-align: center;
}
#loader.hidden { opacity: 0; pointer-events: none; }
#loader .spin {
  width: 46px; height: 46px; border-radius: 50%; margin: 0 auto 16px;
  border: 3px solid var(--border-bright); border-top-color: var(--primary);
  animation: spin 0.9s linear infinite;
}
#loader p { font-family: var(--mono); font-size: 12px; color: var(--text-dim); }
#loader .err { color: var(--danger); max-width: 460px; line-height: 1.6; }
@keyframes spin { to { transform: rotate(360deg); } }

@media (prefers-reduced-motion: reduce) {
  #loader .spin { animation: none; }
  .badge.live .dot { animation: none; }
  * { transition: none !important; }
}

/* ---------------------------------------------------------------- responsive */
@media (max-width: 720px) {
  .overlay { position: static; width: 100%; max-width: none; padding: 12px 12px 0; }
  main { overflow-y: auto; }
  #app { grid-template-rows: auto auto 1fr auto; }
  .brand p { display: none; }
  footer { flex-wrap: wrap; }
  .timeline { order: 3; flex-basis: 100%; }
}