/* 活力红橙 - Layout C */
:root {
  --primary-color: #2c5f8d;
  --secondary-color: #4a7ba7;
  --accent-color: #d4af37;
  --bg-color: #f8f9fa;
  --text-color: #2c3e50;
  --card-bg: #ffffff;
  --border-color: #e1e4e8;
  --hover-bg: #f0f4f8;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background-color: var(--bg-color);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 1.5rem 0;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.logo {
  font-size: 1.8rem;
  font-weight: bold;
  color: white;
  text-decoration: none;
  letter-spacing: 2px;
}

.main-nav ul {
  display: flex;
  list-style: none;
  gap: 0;
  flex-wrap: nowrap;
  align-items: center;
}

.main-nav li {
  flex: 1 1 0;
  min-width: 0;
  text-align: center;
}

.main-nav a {
  color: white;
  text-decoration: none;
  padding: 0.5rem 0.8rem;
  display: block;
  border-radius: 4px;
  transition: all 0.3s;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.main-nav a:hover {
  background: rgba(255,255,255,0.2);
  transform: translateY(-2px);
}

/* Main Content */
.main-content {
  padding: 2rem 0;
  min-height: 60vh;
}

.page-title {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: var(--primary-color);
  border-left: 4px solid var(--accent-color);
  padding-left: 1rem;
}

.intro-section {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  line-height: 1.8;
}

.section {
  margin-bottom: 3rem;
}

.section-title {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-title::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 1.5rem;
  background: var(--accent-color);
}

/* Cards */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.video-card {
  background: var(--card-bg);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: all 0.3s;
  border: 1px solid var(--border-color);
}

.video-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}

.video-card-content {
  padding: 1.5rem;
}

.video-title {
  font-size: 1.2rem;
  margin-bottom: 0.8rem;
  color: var(--primary-color);
}

.video-title a {
  color: inherit;
  text-decoration: none;
  transition: color 0.3s;
}

.video-title a:hover {
  color: var(--secondary-color);
}

.video-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 0.8rem;
  font-size: 0.9rem;
  color: #666;
}

.video-meta span {
  background: var(--hover-bg);
  padding: 0.2rem 0.6rem;
  border-radius: 4px;
}

.video-description {
  color: #555;
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 0.8rem;
}

.video-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.tag {
  background: var(--primary-color);
  color: white;
  padding: 0.2rem 0.6rem;
  border-radius: 12px;
  font-size: 0.85rem;
}

/* List Pages */
.video-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.video-list-item {
  background: var(--card-bg);
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  transition: all 0.3s;
  border-left: 4px solid transparent;
}

.video-list-item:hover {
  border-left-color: var(--accent-color);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.list-item-header {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: 0.8rem;
  flex-wrap: wrap;
}

.rank-number {
  font-size: 2rem;
  font-weight: bold;
  color: var(--accent-color);
  min-width: 50px;
}

.date-tag {
  background: var(--accent-color);
  color: white;
  padding: 0.3rem 0.8rem;
  border-radius: 4px;
  font-size: 0.9rem;
  font-weight: bold;
}

/* Detail Page */
.detail-header {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
}

.detail-title {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.detail-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  font-size: 1.1rem;
}

.detail-section {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.detail-section h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
  border-bottom: 2px solid var(--accent-color);
  padding-bottom: 0.5rem;
}

.detail-section p {
  line-height: 1.8;
  margin-bottom: 1rem;
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.info-item {
  display: flex;
  gap: 0.5rem;
}

.info-label {
  font-weight: bold;
  color: var(--primary-color);
}

/* Footer */
.site-footer {
  background: var(--text-color);
  color: white;
  padding: 2rem 0;
  margin-top: 3rem;
}

.footer-content {
  text-align: center;
}

.footer-nav {
  margin-bottom: 1rem;
}

.footer-nav ul {
  display: flex;
  justify-content: center;
  list-style: none;
  gap: 2rem;
  flex-wrap: wrap;
}

.footer-nav a {
  color: white;
  text-decoration: none;
  transition: opacity 0.3s;
}

.footer-nav a:hover {
  opacity: 0.8;
}

.copyright {
  font-size: 0.9rem;
  opacity: 0.8;
}

/* Group Sections */
.group-section {
  margin-bottom: 3rem;
}

.group-title {
  font-size: 1.3rem;
  color: var(--secondary-color);
  margin-bottom: 1rem;
  padding: 0.5rem 1rem;
  background: var(--hover-bg);
  border-left: 4px solid var(--accent-color);
}

/* Responsive */
@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    align-items: stretch;
  }

  .logo {
    text-align: center;
    font-size: 1.5rem;
  }

  .main-nav ul {
    justify-content: space-between;
    flex-wrap: nowrap;
  }

  .main-nav li {
    flex: 1 1 0;
    min-width: 0;
  }

  .main-nav a {
    padding: 0.5rem 0.3rem;
    font-size: 0.85rem;
  }

  .page-title {
    font-size: 1.5rem;
  }

  .video-grid {
    grid-template-columns: 1fr;
  }

  .detail-title {
    font-size: 1.8rem;
  }

  .rank-number {
    font-size: 1.5rem;
    min-width: 40px;
  }
}

@media (max-width: 480px) {
  .main-nav a {
    font-size: 0.75rem;
    padding: 0.4rem 0.2rem;
  }

  .logo {
    font-size: 1.3rem;
  }
}