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

html, body {
  width: 100%;
  height: 100%;
  background: #000;
  color: #fff;
  font-family: 'Courier New', Courier, monospace;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

#game-container {
  position: relative;
  width: 900px;
  height: 700px;
  margin-top: 80px;
  border: 2px solid #0ff;
  box-shadow:
    0 0 20px #0ff,
    inset 0 0 30px rgba(0, 255, 255, 0.1);
  background: #000;
}

#game {
  display: block;
  width: 100%;
  height: 100%;
}

#hud {
  position: absolute;
  top: 12px;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-around;
  font-size: 20px;
  letter-spacing: 3px;
  color: #0ff;
  text-shadow: 0 0 8px #0ff;
  pointer-events: none;
  user-select: none;
}

#overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  z-index: 10;
}

#overlay.visible {
  display: flex;
}

#overlay h1 {
  font-size: 72px;
  letter-spacing: 14px;
  color: #fff;
  text-shadow:
    0 0 10px #0ff,
    0 0 20px #0ff,
    0 0 40px #0ff;
  margin-bottom: 10px;
  animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
  from { text-shadow: 0 0 10px #0ff, 0 0 20px #0ff; }
  to { text-shadow: 0 0 20px #0ff, 0 0 40px #0ff, 0 0 60px #0ff; }
}

.subtitle {
  font-size: 18px;
  color: #888;
  margin-bottom: 30px;
  letter-spacing: 2px;
}

.controls {
  margin-bottom: 30px;
  line-height: 1.8;
  color: #ccc;
}

.key {
  display: inline-block;
  min-width: 28px;
  padding: 3px 8px;
  margin: 0 3px;
  background: #111;
  border: 1px solid #0ff;
  border-radius: 4px;
  color: #0ff;
  font-size: 14px;
}

button {
  background: transparent;
  border: 2px solid #0ff;
  color: #0ff;
  font-family: inherit;
  font-size: 22px;
  padding: 10px 40px;
  letter-spacing: 4px;
  cursor: pointer;
  transition: all 0.2s;
}

button:hover {
  background: #0ff;
  color: #000;
  box-shadow: 0 0 20px #0ff;
}