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

body {
  font-family: 'Courier New', monospace;
  background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
  color: #ffffff;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.container {
  max-width: 800px;
  width: 100%;
}

header {
  text-align: center;
  margin-bottom: 30px;
}

h1 {
  font-size: 2.5rem;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
  margin-bottom: 10px;
}

.subtitle {
  font-size: 1rem;
  opacity: 0.8;
}

.documentation-link {
  margin-top: 14px;
}

.documentation-link a {
  display: inline-block;
  padding: 10px 14px;
  border: 1px solid rgba(0, 255, 0, 0.35);
  border-radius: 999px;
  color: #b7ffbf;
  text-decoration: none;
  background: rgba(0, 0, 0, 0.2);
}

.documentation-link a:hover,
.documentation-link a:focus {
  color: #ffffff;
  border-color: rgba(0, 255, 0, 0.6);
  background: rgba(0, 255, 0, 0.14);
}

main {
  background: rgba(0, 0, 0, 0.3);
  border-radius: 10px;
  padding: 20px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.game-wrapper {
  display: flex;
  justify-content: center;
  margin-bottom: 30px;
}

#gameCanvas {
  border: 3px solid #00ff00;
  border-radius: 5px;
  box-shadow: 0 0 20px rgba(0, 255, 0, 0.3);
  background: #000000;
}

.controls, .info {
  margin-bottom: 20px;
}

h2 {
  font-size: 1.3rem;
  margin-bottom: 10px;
  color: #00ff00;
}

ul {
  list-style: none;
  padding-left: 20px;
}

li {
  margin-bottom: 8px;
  font-size: 0.9rem;
}

strong {
  color: #00ff00;
}

.power-up {
  color: #ffff00;
  font-weight: bold;
}

footer {
  text-align: center;
  margin-top: 20px;
  font-size: 1.1rem;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

/* Mobile responsive */
@media (max-width: 600px) {
  h1 {
    font-size: 2rem;
  }

  #gameCanvas {
    max-width: 100%;
    height: auto;
  }

  .controls, .info {
    font-size: 0.85rem;
  }
}

/* Accessibility */
:focus {
  outline: 2px solid #00ff00;
  outline-offset: 2px;
}