html, body {
  margin: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #0a1019;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

canvas { display: block; }

#hud {
  position: fixed;
  left: 16px;
  top: 16px;
  z-index: 15;
  max-width: min(660px, calc(100vw - 32px));
  color: #fff;
}

.hud-row {
  display: flex;
  gap: 10px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.panel {
  background: rgba(8, 10, 18, 0.74);
  backdrop-filter: blur(8px);
  border-radius: 14px;
  padding: 10px 14px;
  box-shadow: 0 8px 28px rgba(0,0,0,0.26);
  font-size: 13px;
  line-height: 1.35;
}

.panel strong {
  display: block;
  font-size: 22px;
  line-height: 1.1;
  margin-top: 2px;
}

.panel .label {
  opacity: 0.75;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .04em;
}

.panel.wide {
  max-width: min(660px, calc(100vw - 32px));
  margin-bottom: 10px;
}

#crosshair {
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  z-index: 10;
  color: rgba(255,255,255,.7);
  font-size: 26px;
  user-select: none;
  pointer-events: none;
}

.overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(4, 6, 11, 0.72);
  z-index: 25;
  padding: 24px;
}

.overlay.hidden { display: none; }
.overlay.visible { display: flex; }

.card {
  width: min(640px, calc(100vw - 32px));
  background: rgba(245, 247, 252, 0.96);
  color: #121721;
  border-radius: 22px;
  padding: 24px 26px;
  box-shadow: 0 20px 60px rgba(0,0,0,.35);
}

.card h1, .card h2 { margin-top: 0; }
.card ul { padding-left: 20px; }
.card li { margin: 8px 0; }
.buttons { display: flex; gap: 12px; margin-top: 18px; }
button {
  border: 0;
  border-radius: 12px;
  padding: 12px 18px;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  background: #1373ff;
  color: #fff;
}
button:hover { filter: brightness(1.05); }
.small { font-size: 13px; opacity: .85; }
.big-score { font-size: 56px; font-weight: 800; line-height: 1; margin: 10px 0 4px; }

body.xr-active #hud,
body.xr-active #crosshair {
  display: none;
}