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

body {
  background: #0f172a;
  font-family: 'Press Start 2P', monospace;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  min-height: 100dvh;
  overflow: hidden;
  user-select: none;
  -webkit-user-select: none;
}

.game-container {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  height: 100vh;
  height: 100dvh;
}

#themeToggleBtn {
  position: absolute;
  top: 16px;
  right: 16px;
  z-index: 10;
  background: rgba(15, 23, 42, 0.85);
  color: #ffffff;
  border: 2px solid #38bdf8;
  border-radius: 8px;
  padding: 10px 14px;
  font-family: 'Press Start 2P', monospace;
  font-size: 9px;
  cursor: pointer;
  backdrop-filter: blur(4px);
  transition: transform 0.1s ease, background 0.2s ease, border-color 0.2s ease;
}

#themeToggleBtn:focus-visible {
  outline: 3px solid #facc15;
  outline-offset: 2px;
}

#themeToggleBtn:active {
  transform: scale(0.95);
}

canvas {
  display: block;
  background-color: #70c5ce;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  cursor: pointer;
}

canvas:focus-visible {
  outline: 4px solid #facc15;
  outline-offset: 4px;
}

/* 16:9 Desktop Framing Curve */
@media (min-aspect-ratio: 16/9) {
  canvas {
    border-radius: 12px;
  }
}