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

body {
  background: #111;
  overflow: hidden;
  font-family: 'Courier New', monospace;
  color: #eee;
}

#gameCanvas {
  display: block;
  width: 100vw;
  height: 100vh;
}

.overlay {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0, 0, 0, 0.85);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
}

.overlay.hidden { display: none; }

.menu-box {
  background: #1a1a2e;
  border: 2px solid #0ff;
  border-radius: 8px;
  padding: 32px;
  text-align: center;
  min-width: 320px;
  max-width: 90vw;
  box-shadow: 0 0 30px rgba(0, 255, 255, 0.2);
}

.menu-box.wide {
  min-width: 600px;
  max-width: 800px;
}

.menu-box h1 {
  font-size: 2.5em;
  color: #0ff;
  text-shadow: 0 0 10px #0ff;
  margin-bottom: 8px;
}

.menu-box h2 {
  font-size: 1.8em;
  color: #0ff;
  margin-bottom: 16px;
}

.menu-box h3 {
  color: #0ff;
  margin-bottom: 8px;
  font-size: 1.1em;
}

.subtitle {
  color: #888;
  margin-bottom: 24px;
}

button {
  display: block;
  width: 100%;
  padding: 12px 24px;
  margin: 8px 0;
  background: #16213e;
  color: #0ff;
  border: 1px solid #0ff;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 1em;
  cursor: pointer;
  transition: background 0.2s, box-shadow 0.2s;
}

button:hover {
  background: #0a3d62;
  box-shadow: 0 0 10px rgba(0, 255, 255, 0.4);
}

button:disabled {
  opacity: 0.4;
  cursor: default;
  box-shadow: none;
}

.controls-info {
  margin-top: 24px;
  color: #666;
  font-size: 0.85em;
}

.controls-info p { margin: 4px 0; }

.upgrade-columns {
  display: flex;
  gap: 24px;
  margin-bottom: 16px;
  text-align: left;
}

.upgrade-col {
  flex: 1;
  background: #0d1117;
  padding: 16px;
  border-radius: 4px;
  border: 1px solid #333;
}

.upgrade-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 6px 0;
  border-bottom: 1px solid #222;
}

.upgrade-item span { font-size: 0.9em; }

.upgrade-item button {
  width: auto;
  padding: 4px 12px;
  font-size: 0.8em;
  margin: 0;
}

#tierInfo {
  font-size: 0.9em;
  margin-bottom: 12px;
  line-height: 1.6;
}