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

body {
  background: #0a0a0f;
  overflow: hidden;
  cursor: crosshair;
  height: 100vh;
}

canvas {
  display: block;
  position: fixed;
  top: 0;
  left: 0;
}

#upgrade-screen {
  display: none;
  position: fixed;
  inset: 0;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(6, 6, 14, 0.85);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 24px;
  z-index: 10;
}

#upgrade-screen h2 {
  color: #fff;
  font-family: monospace;
  font-size: 18px;
  letter-spacing: 3px;
  text-transform: uppercase;
}

#upgrade-cards {
  display: flex;
  gap: 16px;
}

.ucard {
  width: 180px;
  padding: 20px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-family: monospace;
  border: 1px solid #333;
  background: #0e0e1a;
  transition: transform .12s, border-color .12s;
  user-select: none;
}

.ucard:hover {
  transform: translateY(-4px);
}

.ucard.common { border-color: #555; }
.ucard.rare   { border-color: #378add; }
.ucard.legend { border-color: #ef9f27; }

.ucard .rarity {
  font-size: 10px;
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 10px;
}

.ucard.common .rarity { color: #888; }
.ucard.rare   .rarity { color: #85b7eb; }
.ucard.legend .rarity { color: #ef9f27; }

.ucard .name {
  font-size: 14px;
  color: #ddd;
  margin-bottom: 8px;
  font-weight: bold;
}

.ucard .desc {
  font-size: 11px;
  color: #777;
  line-height: 1.5;
}

.ucard.common:hover { border-color: #888; }
.ucard.rare:hover   { border-color: #85b7eb; box-shadow: 0 0 12px rgba(55,138,221,0.25); }
.ucard.legend:hover { border-color: #fac775; box-shadow: 0 0 16px rgba(239,159,39,0.3); }