.screen[data-screen="play"] {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  padding: 0;
  overflow: hidden;
}

.screen[data-screen="play"].active {
  display: block;
}

#stage {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  touch-action: none;
}

.tap-shake-btn {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 12px;
  background: linear-gradient(135deg, #F43F5E 0%, #EC4899 50%, #8B5CF6 100%);
  color: #FFFFFF;
  border: 2px solid rgba(255, 255, 255, 0.4);
  border-radius: 999px;
  padding: 16px 42px;
  font-family: var(--font-display, inherit);
  font-size: 22px;
  font-weight: 900;
  letter-spacing: 0.05em;
  box-shadow: 0 0 30px rgba(236, 72, 153, 0.5), 0 10px 20px rgba(0, 0, 0, 0.4);
  cursor: pointer;
  z-index: 10;
  touch-action: manipulation;
  user-select: none;
  transition: transform 0.08s ease, filter 0.08s ease;
}

.tap-shake-btn:hover {
  transform: translateX(-50%) scale(1.04);
}

.tap-shake-btn:active {
  transform: translateX(-50%) scale(0.94);
  filter: brightness(1.2);
}

.shake-ico {
  font-size: 26px;
  display: inline-block;
  animation: shakeWiggle 0.6s infinite ease-in-out;
}

@keyframes shakeWiggle {
  0%, 100% { transform: rotate(0deg); }
  25% { transform: rotate(-14deg); }
  75% { transform: rotate(14deg); }
}

.hint {
  position: absolute;
  top: 80px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(56, 189, 248, 0.3);
  padding: 8px 18px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 14px;
  color: #94A3B8;
  white-space: nowrap;
  pointer-events: none;
  z-index: 5;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

@media (max-height: 600px) {
  .tap-shake-btn {
    bottom: 12px;
    padding: 10px 28px;
    font-size: 18px;
  }
}