:root {
  /* 화이트 테마 (기본) */
  --bg-color: #f8f9fa;
  --text-color: #212529;
  --card-bg: #ffffff;
  --accent-color: #007bff;
  --btn-text: #ffffff;
  --input-bg: #fdfdfd;
  --input-border: #dee2e6;
  --input-text: #212529;
}

[data-theme='dark'] {
  --bg-color: #121212;
  --text-color: #e0e0e0;
  --card-bg: #1e1e1e;
  --accent-color: #bb86fc;
  --btn-text: #000000;
  --input-bg: #2d2d2d;
  --input-border: #444;
  --input-text: #f0f0f0;
}

[data-theme='yellow'] {
  --bg-color: #fffde7;
  --text-color: #5d4037;
  --card-bg: #fff9c4;
  --accent-color: #fbc02d;
  --btn-text: #212121;
  --input-bg: #fffde7;
  --input-border: #ffe082;
  --input-text: #5d4037;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  margin: 0;
  padding: 2rem 0;
}

.container {
  background-color: var(--card-bg);
  padding: 2rem;
  border-radius: 1.5rem;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
  text-align: center;
  max-width: 500px;
  width: 90%;
}

.theme-selector {
  margin-bottom: 2rem;
  display: flex;
  gap: 10px;
  justify-content: center;
}

.theme-btn {
  padding: 8px 16px;
  border: none;
  border-radius: 20px;
  cursor: pointer;
  font-weight: bold;
  font-size: 0.8rem;
  transition: transform 0.2s;
}

.theme-btn:hover { transform: scale(1.05); }

.lotto-container {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin: 2rem 0;
  flex-wrap: wrap;
}

.ball {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  font-size: 1.2rem;
  color: white;
  text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
  box-shadow: 0 4px 10px rgba(0,0,0,0.2);
  animation: pop 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes pop {
  0% { transform: scale(0.5); opacity: 0; }
  100% { transform: scale(1); opacity: 1; }
}

.action-btn {
  background-color: var(--accent-color);
  color: var(--btn-text);
  border: none;
  padding: 12px 24px;
  font-size: 1.1rem;
  font-weight: bold;
  border-radius: 30px;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.1s;
}

.action-btn:active { transform: scale(0.95); }

/* --- Contact Form Styles --- */
.contact-section {
  text-align: left;
}

.contact-section h3 {
  text-align: center;
  margin-bottom: 1.5rem;
}

.form-group {
  margin-bottom: 1rem;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
  font-weight: 500;
  opacity: 0.8;
}

.form-group input, .form-group textarea {
  width: 100%;
  padding: 12px;
  border-radius: 12px;
  border: 1px solid var(--input-border);
  background-color: var(--input-bg);
  color: var(--input-text);
  font-size: 1rem;
  box-sizing: border-box;
  transition: border-color 0.2s;
}

.form-group input:focus, .form-group textarea:focus {
  outline: none;
  border-color: var(--accent-color);
}