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

body {
  background: #000;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  font-family: 'Courier New', monospace;
  overflow: hidden;
}

#game-container {
  position: relative;
  width: 800px;
  height: 500px;
}

#hud {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  background: #000;
  color: #fff;
  padding: 6px 16px;
  font-size: 13px;
  font-weight: bold;
  letter-spacing: 1px;
  height: 36px;
}

#hud span {
  white-space: nowrap;
}

#sound-toggle {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  background: transparent;
  color: #fff;
  border: none;
  padding: 0;
  font-size: 11px;
  font-family: 'Courier New', monospace;
  font-weight: bold;
  cursor: pointer;
  letter-spacing: 1px;
}

.sound-switch {
  position: relative;
  width: 38px;
  height: 20px;
  border: 2px solid #fff;
  border-radius: 999px;
  background: #2dbb4f;
  transition: background 0.15s;
}

.sound-switch span {
  position: absolute;
  top: 2px;
  left: 20px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #fff;
  box-shadow: 0 0 0 1px #000;
  transition: left 0.15s;
}

#sound-toggle.is-muted .sound-switch {
  background: #e52521;
}

#sound-toggle.is-muted .sound-switch span {
  left: 2px;
}

#gameCanvas {
  display: block;
  background: #5c94fc;
  width: 800px;
  height: 464px;
}

#overlay {
  position: absolute;
  top: 36px;
  left: 0;
  width: 100%;
  height: calc(100% - 36px);
  background: rgba(0, 0, 0, 0.75);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  color: #fff;
  text-align: center;
  z-index: 10;
}

#overlay.hidden {
  display: none;
}

#overlay-title {
  font-size: 48px;
  color: #e52521;
  text-shadow: 3px 3px 0 #000;
  margin-bottom: 20px;
  letter-spacing: 4px;
}

#overlay-msg {
  font-size: 16px;
  color: #fff;
  margin-bottom: 30px;
  line-height: 2;
}

#overlay-btn {
  background: #e52521;
  color: #fff;
  border: none;
  padding: 12px 36px;
  font-size: 18px;
  font-family: 'Courier New', monospace;
  font-weight: bold;
  cursor: pointer;
  letter-spacing: 2px;
  border-radius: 4px;
  transition: background 0.15s;
}

#overlay-btn:hover {
  background: #ff4a46;
}