body {
  font-family: Arial, sans-serif;
  background: #f6f7fb;
  text-align: center;
  padding: 40px;
}

h1 {
  margin-bottom: 30px;
}

#category-container {
  display: grid;
  grid-template-columns: repeat(2, 180px);
  gap: 20px;
  justify-content: center;
}

.category-button {
  padding: 20px;
  font-size: 18px;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  background: white;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  transition: all 0.2s ease;
}

.category-button:hover {
  transform: translateY(-3px);
  background: #4f46e5;
  color: white;
}

.top-bar {
  display: flex;
  justify-content: space-between;
  padding: 10px 40px;
  font-size: 24px;
}

canvas {
  border: 2px solid black;
  margin-top: 10px;
}

.controls {
  position: fixed;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);

  display: flex;
  gap: 40px;
}

.controls button {
  width: 80px;
  height: 80px;
  font-size: 26px;

  border-radius: 50%;
  border: none;
  cursor: pointer;

  background: #7e79d9;
  color: white;
  box-shadow: 0 6px 15px rgba(0,0,0,0.25);
}

.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.7);
  color: white;
  font-size: 100px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.hidden {
  display: none;
}

canvas {
  touch-action: none; /* 터치 스크롤 방지 */
}

.nav-btn {
  width: 60px;
  height: 60px;
  font-size: 28px;
  border-radius: 12px;
  border: none;
  cursor: pointer;
  background: #e5e7eb;
}

.pass-btn {
  width: 90px;
  height: 90px;
  border-radius: 50%;
  font-size: 18px;
  font-weight: bold;
  border: none;
  cursor: pointer;
  background: #ef4444;
  color: white;
}

.tool-bar {
  position: fixed;
  top: 20px;
  right: 20px;

  display: flex;
  gap: 10px;
}

.tool-bar button {
  width: 48px;
  height: 48px;
  font-size: 20px;

  border-radius: 50%;
  border: none;
  cursor: pointer;

  background: white;
  box-shadow: 0 4px 10px rgba(0,0,0,0.15);
}