* { box-sizing: border-box; }

html, body {
  height: 100%;
  margin: 0;
}

body {
  background: radial-gradient(circle at 50% 35%, #33323a 0%, #0c0c0f 75%);
  font-family: "Helvetica Neue", Arial, "Apple SD Gothic Neo", sans-serif;
  overflow: hidden;
}

.stage {
  position: fixed;
  inset: 0;
}

#book3d {
  position: absolute;
  inset: 0;
  cursor: grab;
}

#book3d:active { cursor: grabbing; }

#book3d canvas { display: block; }

.caption {
  position: absolute;
  top: 4.5vh;
  left: 0;
  right: 0;
  text-align: center;
  pointer-events: none;
  color: #e8e8ec;
}

.caption h1 {
  margin: 0;
  font-size: clamp(20px, 3.2vw, 34px);
  font-weight: 800;
  letter-spacing: 0.14em;
}

.caption p {
  margin: 6px 0 0;
  font-size: 13px;
  color: #8a8a94;
  letter-spacing: 0.06em;
}

.controls {
  position: fixed;
  bottom: 4vh;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(8px);
}

.controls button {
  border: 1px solid rgba(255, 255, 255, 0.25);
  background: rgba(255, 255, 255, 0.12);
  color: #eee;
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 14px;
  cursor: pointer;
  white-space: nowrap;
}

.controls button:hover { background: rgba(255, 255, 255, 0.22); }

.controls .stat {
  color: #999;
  font-size: 13px;
  margin-left: 6px;
  white-space: nowrap;
}