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

body {
  font-family: 'Courier New', monospace;
  background: linear-gradient(to bottom, #000428, #004e92);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  color: #fff;
  overflow: hidden;
}

#game-container {
  position: relative;
  width: 800px;
  height: 600px;
  border: 4px solid #00ff00;
  border-radius: 8px;
  box-shadow: 0 0 40px rgba(0, 255, 0, 0.3), inset 0 0 20px rgba(0, 255, 0, 0.1);
  background: #000;
  overflow: hidden;
}

#gameCanvas {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(to bottom, #000 0%, #001a33 100%);
}

#game-ui {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  padding: 15px 20px;
  background: rgba(0, 0, 0, 0.7);
  border-bottom: 2px solid #00ff00;
  z-index: 10;
}

.ui-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.label {
  font-size: 12px;
  color: #00ff00;
  letter-spacing: 2px;
  text-shadow: 0 0 5px #00ff00;
}

.value {
  font-size: 24px;
  font-weight: bold;
  color: #fff;
  text-shadow: 0 0 10px #00ff00;
}

.screen {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.95);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 100;
  gap: 20px;
  text-align: center;
}

.hidden {
  display: none !important;
}

.screen h1 {
  font-size: 48px;
  color: #00ff00;
  text-shadow: 0 0 20px #00ff00, 0 0 40px #00ff00;
  letter-spacing: 8px;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}

.screen p {
  font-size: 18px;
  color: #aaa;
  line-height: 1.6;
}

.screen button {
  padding: 15px 40px;
  font-size: 20px;
  font-family: 'Courier New', monospace;
  font-weight: bold;
  background: transparent;
  color: #00ff00;
  border: 3px solid #00ff00;
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.3s;
  text-transform: uppercase;
  letter-spacing: 2px;
  text-shadow: 0 0 5px #00ff00;
  box-shadow: 0 0 10px rgba(0, 255, 0, 0.3);
}

.screen button:hover {
  background: #00ff00;
  color: #000;
  box-shadow: 0 0 20px rgba(0, 255, 0, 0.8);
  transform: scale(1.05);
}

.instructions {
  margin-top: 20px;
  padding: 20px;
  border: 2px solid #00ff00;
  border-radius: 5px;
  background: rgba(0, 255, 0, 0.05);
  max-width: 80%;
}

.instructions p {
  font-size: 14px;
  margin: 5px 0;
}

.instructions strong {
  color: #00ff00;
  font-size: 16px;
}

#final-score {
  color: #00ff00;
  font-size: 36px;
  font-weight: bold;
  text-shadow: 0 0 10px #00ff00;
}

#level-number {
  color: #00ff00;
  text-shadow: 0 0 15px #00ff00;
}

/* Responsive */
@media (max-width: 850px) {
  #game-container {
    width: 95vw;
    height: 71.25vw;
    max-height: 95vh;
  }
  
  .screen h1 {
    font-size: 32px;
  }
  
  .screen button {
    font-size: 16px;
    padding: 12px 30px;
  }
  
  #game-ui {
    padding: 8px 10px;
  }
  
  .label {
    font-size: 10px;
  }
  
  .value {
    font-size: 18px;
  }
}