:root {
  --background-color: #f8f9fa;
  --card-background-color: #ffffff;
  --primary-color: #2c3e50;
  --secondary-color: #3498db;
  --accent-color: #e67e22;
  --text-color: #333333;
  --sub-text-color: #666666;
  --shadow-color: rgba(0, 0, 0, 0.08);
  --font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
}

body.dark-theme {
  --background-color: #1a1a1a;
  --card-background-color: #2d2d2d;
  --primary-color: #ecf0f1;
  --secondary-color: #5dade2;
  --accent-color: #f39c12;
  --text-color: #e0e0e0;
  --sub-text-color: #aaaaaa;
  --shadow-color: rgba(0, 0, 0, 0.4);
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family);
  background-color: var(--background-color);
  color: var(--text-color);
  line-height: 1.6;
  transition: background-color 0.4s ease, color 0.4s ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Smooth transition for all UI elements */
* {
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

/* Main Navigation */
.main-nav {
  position: sticky;
  top: 0;
  background-color: var(--card-background-color);
  box-shadow: 0 2px 8px var(--shadow-color);
  z-index: 1001;
  padding: 0.8rem 0;
}

.nav-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--secondary-color);
  text-decoration: none;
}

.nav-links a {
  margin-left: 1.5rem;
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

.nav-links a:hover {
  color: var(--secondary-color);
}

/* Info Sections (About & Privacy) */
.info-section {
  max-width: 800px;
  margin: 3rem auto;
  padding: 2rem;
  background-color: var(--card-background-color);
  border-radius: 16px;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.info-section h2 {
  color: var(--secondary-color);
  margin-top: 0;
  margin-bottom: 1.5rem;
  font-size: 1.5rem;
  text-align: center;
}

.info-section p {
  color: var(--sub-text-color);
  line-height: 1.8;
  font-size: 1rem;
  margin-bottom: 0;
}

.privacy-section {
  background-color: rgba(52, 152, 219, 0.05);
  font-size: 0.9rem;
  margin-bottom: 0;
}

body.dark-theme .privacy-section {
  background-color: rgba(93, 173, 226, 0.05);
}

.faq-item {
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--shadow-color);
  padding-bottom: 1rem;
}

.faq-item:last-child {
  border-bottom: none;
  margin-bottom: 0;
}

.faq-item h3 {
  font-size: 1.1rem;
  color: var(--text-color);
  margin-bottom: 0.5rem;
}

.faq-item p {
  font-size: 0.95rem;
  color: var(--sub-text-color);
}

.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  cursor: pointer;
  background: var(--card-background-color);
  border: 1px solid var(--secondary-color);
  color: var(--text-color);
  padding: 8px 16px;
  border-radius: 20px;
  font-weight: 600;
  transition: all 0.3s ease;
  z-index: 1000;
  box-shadow: 0 2px 4px var(--shadow-color);
}

header {
  text-align: center;
  padding: 4rem 1rem 2rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  margin-bottom: 2rem;
}

header h1 {
  margin: 0;
  font-size: 2.5rem;
  font-weight: 800;
}

header p {
  opacity: 0.9;
  font-size: 1.1rem;
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem 4rem;
  flex: 1;
}

.benefit-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  min-height: 200px;
}

.ad-container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1rem;
  text-align: center;
  overflow: hidden;
}

.top-ad {
  margin-top: -1rem;
}

.bottom-ad {
  margin-bottom: 3rem;
}

.no-results {
  grid-column: 1 / -1;
  text-align: center;
  padding: 3rem;
  font-size: 1.2rem;
  color: var(--sub-text-color);
  background-color: var(--card-background-color);
  border-radius: 16px;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.search-section {
  max-width: 600px;
  margin: 0 auto 3rem;
  padding: 0 1rem;
}

#benefit-search {
  width: 100%;
  padding: 1rem 1.5rem;
  border-radius: 30px;
  border: 2px solid var(--secondary-color);
  background-color: var(--card-background-color);
  color: var(--text-color);
  font-size: 1.1rem;
  font-family: inherit;
  box-shadow: 0 4px 12px var(--shadow-color);
  transition: all 0.3s ease;
}

#benefit-search:focus {
  outline: none;
  box-shadow: 0 6px 16px var(--shadow-color);
  transform: translateY(-2px);
}

.benefit-card {
  background-color: var(--card-background-color);
  border-radius: 16px;
  padding: 1.5rem;
  box-shadow: 0 4px 12px var(--shadow-color);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.3s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  animation: fadeInUp 0.6s ease backwards;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.benefit-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 24px var(--shadow-color);
}

.card-content {
  margin-bottom: 1.5rem;
}

.benefit-card h3 {
  color: var(--secondary-color);
  margin-top: 0;
  font-size: 1.3rem;
}

.benefit-card .amount {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-color);
  margin: 0.5rem 0;
}

.benefit-card .period {
  font-size: 0.9rem;
  color: var(--accent-color);
  margin-bottom: 1rem;
  background-color: rgba(230, 126, 34, 0.1);
  padding: 4px 8px;
  border-radius: 4px;
  display: inline-block;
}

body.dark-theme .benefit-card .period {
  background-color: rgba(243, 156, 18, 0.1);
}

.benefit-card p {
  font-size: 0.95rem;
  color: var(--sub-text-color);
  margin-bottom: 0;
}

.apply-btn {
  display: block;
  text-align: center;
  background-color: var(--secondary-color);
  color: white;
  text-decoration: none;
  padding: 10px;
  border-radius: 8px;
  font-weight: 600;
  transition: background-color 0.2s ease;
}

.apply-btn:hover {
  background-color: var(--primary-color);
}

footer {
  text-align: center;
  padding: 2rem;
  font-size: 0.9rem;
  color: var(--sub-text-color);
}

@media (max-width: 600px) {
  header h1 {
    font-size: 1.8rem;
  }
  .benefit-grid {
    grid-template-columns: 1fr;

  }
}

.contact-section {
  margin-top: 4rem;
  padding: 2rem;
  background-color: var(--card-background-color);
  border-radius: 16px;
  box-shadow: 0 4px 12px var(--shadow-color);
}

.contact-section h2 {
  color: var(--secondary-color);
  text-align: center;
  margin-bottom: 1rem;
}

.contact-section p {
  text-align: center;
  color: var(--sub-text-color);
  margin-bottom: 2rem;
}

.contact-form {
  max-width: 600px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-color);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.8rem;
  border: 1px solid var(--sub-text-color);
  border-radius: 8px;
  background-color: var(--background-color);
  color: var(--text-color);
  font-family: inherit;
  font-size: 1rem;
  box-sizing: border-box;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--secondary-color);
  box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

.submit-btn {
  width: 100%;
  padding: 1rem;
  background-color: var(--secondary-color);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 1.1rem;
  font-weight: 700;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.submit-btn:hover {
  background-color: var(--primary-color);
}