/* Math You Walk Inside — WebXR prototype
   Platform palette */
:root {
  --navy: #12355b;
  --teal: #1fa6a2;
  --amber: #f2c15b;
  --cream: #f7f4ec;
  --ink: #21313f;
  --shadow: 0 6px 24px rgba(18, 53, 91, 0.22);
  --radius: 14px;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
  overflow: hidden;
  font-family:
    "Segoe UI",
    system-ui,
    -apple-system,
    Arial,
    sans-serif;
  background: var(--ink);
  color: var(--cream);
}

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

/* ---- Top banner / scene switcher ---- */
#top-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  background: linear-gradient(
    180deg,
    rgba(18, 53, 91, 0.96),
    rgba(18, 53, 91, 0.78)
  );
  box-shadow: var(--shadow);
}

#top-bar h1 {
  margin: 0;
  font-size: 1.35rem;
  color: var(--cream);
  letter-spacing: 0.3px;
}

#top-bar h1 .accent {
  color: var(--amber);
}

.switcher {
  display: flex;
  gap: 8px;
  margin-left: auto;
}

.scene-btn {
  font-size: 1.05rem;
  font-weight: 700;
  padding: 10px 18px;
  border: 2px solid transparent;
  border-radius: 999px;
  background: rgba(247, 244, 236, 0.16);
  color: var(--cream);
  cursor: pointer;
  transition:
    background 0.15s,
    border-color 0.15s,
    transform 0.1s;
}
.scene-btn:hover {
  background: rgba(247, 244, 236, 0.28);
}
.scene-btn:active {
  transform: scale(0.97);
}
.scene-btn[aria-pressed="true"] {
  background: var(--teal);
  border-color: var(--amber);
  color: #fff;
}

/* ---- Instruction panel ---- */
#instructions {
  position: fixed;
  left: 18px;
  bottom: 18px;
  z-index: 10;
  max-width: min(420px, 80vw);
  padding: 18px 20px;
  border-radius: var(--radius);
  background: rgba(247, 244, 236, 0.96);
  color: var(--ink);
  box-shadow: var(--shadow);
  border-left: 8px solid var(--teal);
}
#instructions h2 {
  margin: 0 0 6px;
  font-size: 1.25rem;
  color: var(--navy);
}
#instructions p {
  margin: 6px 0;
  font-size: 1.05rem;
  line-height: 1.45;
}
#instructions ul {
  margin: 6px 0 0;
  padding-left: 20px;
  font-size: 1.02rem;
  line-height: 1.5;
}
#instructions .standard {
  display: inline-block;
  margin-top: 10px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--teal);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ---- Live readout (HUD) ---- */
#readout {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 10;
  min-width: 230px;
  padding: 18px 20px;
  border-radius: var(--radius);
  background: rgba(18, 53, 91, 0.95);
  color: var(--cream);
  box-shadow: var(--shadow);
  border-left: 8px solid var(--amber);
  text-align: center;
}
#readout .label {
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--amber);
  margin-bottom: 4px;
}
#readout .formula {
  font-size: 1.6rem;
  font-weight: 800;
  line-height: 1.3;
}
#readout .formula .v {
  color: var(--amber);
}
#readout .sub {
  font-size: 1.05rem;
  margin-top: 6px;
  opacity: 0.95;
}
#readout .celebrate {
  margin-top: 10px;
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--amber);
  display: none;
}
#readout.is-complete {
  border-left-color: var(--teal);
}
#readout.is-complete .celebrate {
  display: block;
}

/* ---- Controls hint / reset ---- */
.control-row {
  display: flex;
  gap: 8px;
  margin-top: 12px;
  justify-content: center;
  flex-wrap: wrap;
}
.mini-btn {
  font-size: 0.95rem;
  font-weight: 700;
  padding: 8px 14px;
  border: 2px solid var(--amber);
  border-radius: 999px;
  background: transparent;
  color: var(--cream);
  cursor: pointer;
}
.mini-btn:hover {
  background: rgba(242, 193, 91, 0.2);
}

/* ---- VR button (injected) ---- */
#xr-button-wrap {
  position: fixed;
  top: 70px;
  right: 18px;
  z-index: 11;
}
#xr-button-wrap button {
  font-size: 1rem !important;
  font-weight: 700 !important;
  padding: 10px 18px !important;
  border-radius: 999px !important;
  background: var(--amber) !important;
  color: var(--navy) !important;
  border: none !important;
  cursor: pointer;
  box-shadow: var(--shadow);
  opacity: 1 !important;
}

@media (max-width: 640px) {
  #top-bar h1 {
    font-size: 1.05rem;
    width: 100%;
  }
  .switcher {
    margin-left: 0;
  }
  #instructions {
    max-width: 64vw;
    padding: 12px 14px;
  }
  #instructions p,
  #instructions ul {
    font-size: 0.95rem;
  }
  #readout {
    min-width: 160px;
    padding: 12px 14px;
  }
  #readout .formula {
    font-size: 1.25rem;
  }
}

/* ---- control buttons: pin above the fixed canvas, readable on any scene ---- */
.control-row {
  position: fixed;
  left: 50%;
  bottom: 20px;
  transform: translateX(-50%);
  z-index: 11;
  margin: 0;
}
.control-row .mini-btn {
  background: rgba(18, 53, 91, 0.95);
  color: var(--cream);
  box-shadow: var(--shadow);
}
.control-row .mini-btn:hover {
  background: rgba(18, 53, 91, 0.8);
}

/* fix: no transform (it captured the fixed #readout); center via left/right + click-through */
.control-row {
  left: 0;
  right: 0;
  transform: none;
  pointer-events: none;
}
.control-row .mini-btn {
  pointer-events: auto;
}