* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  user-select: none;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: #060713;
  touch-action: none;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: #ffffff;
}

#game-container {
  position: relative;
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  background: radial-gradient(circle at 50% 50%, #0d0e26 0%, #050612 100%);
}

#gameCanvas {
  display: block;
  width: 100%;
  height: 100%;
  outline: none;
  touch-action: none;
}

#hud-overlay {
  position: absolute;
  top: 16px;
  left: 16px;
  right: 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  pointer-events: none;
  z-index: 10;
}

.hud-card {
  background: rgba(13, 14, 38, 0.65);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(0, 243, 255, 0.25);
  border-radius: 8px;
  padding: 8px 14px;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
}

.hud-label {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 1px;
  color: #a0a5cf;
}

.hud-value {
  font-size: 16px;
  font-weight: 900;
  color: #00f3ff;
}

#shield-val {
  color: #ff2a85;
}

#score-val {
  color: #ffffff;
}

#controls-overlay {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 12px;
  z-index: 20;
  pointer-events: auto;
}

.hud-btn {
  font-family: inherit;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.5px;
  padding: 10px 20px;
  border-radius: 20px;
  border: 1px solid rgba(0, 243, 255, 0.4);
  background: rgba(6, 7, 19, 0.85);
  color: #00f3ff;
  cursor: pointer;
  box-shadow: 0 0 12px rgba(0, 243, 255, 0.2);
  transition: all 0.2s ease;
  outline: none;
}

.hud-btn:hover, .hud-btn:focus {
  background: rgba(0, 243, 255, 0.25);
  color: #ffffff;
  box-shadow: 0 0 20px rgba(0, 243, 255, 0.5);
  transform: scale(1.05);
}

.primary-btn {
  border-color: rgba(255, 215, 0, 0.6);
  color: #ffd700;
  box-shadow: 0 0 12px rgba(255, 215, 0, 0.2);
}

.primary-btn:hover, .primary-btn:focus {
  background: rgba(255, 215, 0, 0.25);
  color: #ffffff;
  box-shadow: 0 0 20px rgba(255, 215, 0, 0.5);
}

.hidden-btn {
  display: none;
}