* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #0a0c14;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  color: #eef1f8;
  -webkit-user-select: none;
  user-select: none;
}

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

/* ---- HUD ---- */
#hud {
  position: fixed;
  top: 14px;
  left: 14px;
  z-index: 10;
  background: rgba(14, 17, 26, 0.72);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.09);
  border-radius: 16px;
  padding: 14px 16px;
  min-width: 232px;
}

#hud .brand {
  font-size: 1.08rem;
  font-weight: 800;
  letter-spacing: 0.3px;
  margin-bottom: 12px;
}

#hud .grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 10px;
}

#hud .cell {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 10px;
  padding: 7px 10px;
  display: flex;
  flex-direction: column;
}

#hud .cell .k {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: #8b93ab;
}

#hud .cell .v {
  font-size: 1.18rem;
  font-weight: 800;
  color: #8fa6ff;
  font-variant-numeric: tabular-nums;
}

#combo {
  height: 20px;
  margin-bottom: 8px;
  font-size: 0.86rem;
  font-weight: 800;
  color: #ffd166;
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.12s, transform 0.12s;
}

#combo.on {
  opacity: 1;
  transform: scale(1);
}

#hud .buttons {
  display: flex;
  gap: 8px;
}

#hud button {
  font: inherit;
  font-size: 0.86rem;
  font-weight: 700;
  cursor: pointer;
  padding: 8px 12px;
  border-radius: 9px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #fff;
}

#newBtn {
  flex: 1;
  background: linear-gradient(180deg, #6c8cff, #4a6bff);
  border-color: transparent;
}

#muteBtn {
  background: rgba(255, 255, 255, 0.06);
  width: 42px;
}

#hud button:active {
  transform: translateY(1px);
}

#hud .hint {
  margin-top: 10px;
  font-size: 0.74rem;
  color: #717a96;
}

/* ---- Level overlay ---- */
#overlay {
  position: fixed;
  inset: 0;
  z-index: 15;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.25s;
}

#overlay.show {
  opacity: 1;
}

#overlayText {
  font-size: clamp(1.6rem, 6vw, 3.4rem);
  font-weight: 900;
  letter-spacing: 1px;
  text-align: center;
  color: #fff;
  text-shadow: 0 6px 30px rgba(108, 140, 255, 0.55);
  transform: scale(0.8);
  transition: transform 0.3s cubic-bezier(0.18, 1.3, 0.4, 1);
}

#overlay.show #overlayText {
  transform: scale(1);
}

/* ---- misc ---- */
#build {
  position: fixed;
  bottom: 9px;
  right: 11px;
  z-index: 30;
  font: 11px ui-monospace, Consolas, monospace;
  color: #59617c;
  letter-spacing: 1px;
  pointer-events: none;
}

#error {
  position: fixed;
  inset: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #0a0c14;
  color: #ff8a93;
  font-size: 1rem;
  padding: 30px;
  text-align: center;
}

@media (max-width: 560px) {
  #hud {
    min-width: 0;
    left: 8px;
    right: 8px;
    top: calc(env(safe-area-inset-top, 0px) + 8px);
    padding: 9px 10px;
    border-radius: 13px;
  }
  #hud .brand {
    font-size: 0.95rem;
    margin-bottom: 8px;
  }
  #hud .grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 6px;
    margin-bottom: 7px;
  }
  #hud .cell {
    padding: 5px 7px;
  }
  #hud .cell .k {
    font-size: 0.58rem;
  }
  #hud .cell .v {
    font-size: 0.98rem;
  }
  #combo {
    height: 16px;
    font-size: 0.76rem;
    margin-bottom: 6px;
  }
  #hud button {
    padding: 7px 10px;
    font-size: 0.8rem;
  }
  #hud .hint {
    display: none;
  }
}