:root {
  --primary-color: #4a90e2;
  --bg-color: #f0f2f5;
  --card-bg: #ffffff;
}

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

body {
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-color);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.container {
  background-color: var(--card-bg);
  padding: 3rem;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
  text-align: center;
  max-width: 500px;
  width: 90%;
}

h1 {
  margin-bottom: 0.5rem;
  color: #333;
}

.subtitle {
  color: #666;
  margin-bottom: 2rem;
}

.balls-container {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 2.5rem;
  flex-wrap: nowrap; /* 무조건 한 줄로 표시 */
}

.ball {
  flex-shrink: 0; /* 크기가 줄어들지 않도록 설정 */
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: bold;
  font-size: 1.1rem;
  color: white;
  box-shadow: 0 4px 6px rgba(0,0,0,0.15);
  transition: transform 0.3s ease;
  animation: popIn 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@media (max-width: 480px) {
  .balls-container {
    gap: 5px;
  }
  .ball {
    width: 40px;
    height: 40px;
    font-size: 0.9rem;
  }
}

.ball.placeholder {
  background-color: #eee;
  color: #aaa;
  box-shadow: none;
}

/* 로또 번호별 색상 */
.ball-1-10 { background-color: #fbc400; text-shadow: 0 1px 2px rgba(0,0,0,0.2); }
.ball-11-20 { background-color: #69c8f2; }
.ball-21-30 { background-color: #ff7272; }
.ball-31-40 { background-color: #aaa; }
.ball-41-45 { background-color: #b0d840; }

.generate-btn {
  background-color: var(--primary-color);
  color: white;
  border: none;
  padding: 1rem 2rem;
  font-size: 1.1rem;
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.2s;
  font-weight: 600;
}

.generate-btn:hover {
  background-color: #357abd;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(74, 144, 226, 0.3);
}

.generate-btn:active {
  transform: translateY(0);
}

@keyframes popIn {
  from {
    transform: scale(0);
    opacity: 0;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}