html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}

body {
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  overflow: hidden;
  background: transparent; /* Arka planı tamamen saydam yap */
}
.background-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  z-index: 0;
  pointer-events: none;
  opacity: 1;
  transition: opacity 0.3s;
}
canvas {
  background: linear-gradient(90deg, rgba(20,30,48,0.7) 0%, rgba(36,59,85,0.7) 100%);
  border-radius: 18px;
  box-shadow: 0 12px 40px #000a, 0 0 0 2px #243b55 inset;
  display: block;
  border: 2px solid #243b55;
  z-index: 1;
}
#score {
  position: absolute;
  top: 32px;
  left: 50%;
  transform: translateX(-50%);
  color: #00ffea;
  font-family: 'Share Tech Mono', monospace;
  font-size: 2em;
  text-shadow: 0 0 12px #00ffea99, 0 0 2px #243b55;
  z-index: 2;
  letter-spacing: 2px;
  padding: 8px 24px;
  background: rgba(20, 30, 48, 0.7);
  border-radius: 12px;
  border: 1px solid #243b55;
  box-shadow: 0 2px 12px #00ffea22;
}
.cube-select {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background: rgba(20,30,48,0.85);
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.cube-select h2 {
  font-family: 'Share Tech Mono', monospace;
  font-size: 2.4em;
  color: #00ffea;
  text-shadow: 0 0 24px #00ffea99, 0 2px 8px #222;
  letter-spacing: 4px;
  margin-bottom: 18px;
  background: linear-gradient(90deg, #00ffea 0%, #ffd700 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-fill-color: transparent;
  font-weight: bold;
  border-radius: 8px;
  padding: 8px 0;
}
#cube-options {
  display: flex;
  gap: 24px;
  margin: 24px 0;
}
.cube-option {
  width: 64px;
  height: 64px;
  border-radius: 12px;
  border: 3px solid #00ffea;
  cursor: pointer;
  transition: box-shadow 0.2s, border-color 0.2s;
  box-shadow: 0 2px 12px #00ffea44;
}
.cube-option.selected {
  border-color: #ffd700;
  box-shadow: 0 0 24px #ffd70088;
}
#start-btn {
  padding: 12px 32px;
  font-size: 1.2em;
  border-radius: 8px;
  border: none;
  background: #00ffea;
  color: #222;
  cursor: pointer;
  font-family: inherit;
  margin-top: 12px;
}