/* 全局样式重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, 'Noto Sans', sans-serif;
  line-height: 1.6;
  color: #1a1a2e;
  background: #f0f4f8;
  overflow-x: hidden;
}

.app {
  min-height: 100vh;
}

/* 顶部通知栏 */
.top-banner {
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 100%);
  color: white;
  padding: 10px 0;
  text-align: center;
  animation: slideDown 0.5s ease-out;
}

.banner-content {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-size: 14px;
}

.banner-icon {
  font-size: 18px;
  animation: bounce 2s infinite;
}

/* 头部导航 */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: white;
  box-shadow: 0 2px 20px rgba(15, 76, 117, 0.1);
}

.header-wrapper {
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 100%);
}

.header-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 75px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  transition: transform 0.3s ease;
}

.logo:hover {
  transform: scale(1.05);
}

.logo-icon {
  font-size: 40px;
  filter: drop-shadow(0 2px 4px rgba(0,0,0,0.2));
}

.logo-info {
  display: flex;
  flex-direction: column;
}

.logo-text {
  font-size: 24px;
  font-weight: 700;
  color: white;
  letter-spacing: 1px;
}

.logo-subtitle {
  font-size: 12px;
  color: rgba(255,255,255,0.9);
  letter-spacing: 2px;
}

.nav {
  display: flex;
  gap: 8px;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 16px;
  color: rgba(255,255,255,0.9);
  text-decoration: none;
  border-radius: 10px;
  transition: all 0.3s ease;
  font-size: 15px;
  font-weight: 500;
}

.nav-link:hover {
  background: rgba(255,255,255,0.15);
  color: white;
  transform: translateY(-2px);
}

.nav-link.active {
  background: rgba(255,255,255,0.25);
  color: white;
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.nav-icon {
  font-size: 20px;
}

/* 英雄区 */
.hero-section {
  position: relative;
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 50%, #3282b8 100%);
  color: white;
  padding: 100px 20px 80px;
  overflow: hidden;
}

.hero-background {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 200px;
  overflow: hidden;
}

.wave {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 200%;
  height: 100%;
  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1200 120'%3E%3Cpath d='M0,0V46.29c47.79,22.2,103.59,32.17,158,28,70.36-5.37,136.33-33.31,206.8-37.5C438.64,32.43,512.34,53.67,583,72.05c69.27,18,138.3,24.88,209.4,13.08,36.15-6,69.85-17.84,104.45-29.34C989.49,25,1113-14.29,1200,52.47V0Z' fill='rgba(255,255,255,0.1)'/%3E%3C/svg%3E") repeat-x;
  animation: wave 25s linear infinite;
}

.wave1 {
  opacity: 0.7;
  animation-duration: 25s;
}

.wave2 {
  opacity: 0.5;
  animation-duration: 30s;
  animation-direction: reverse;
}

.wave3 {
  opacity: 0.3;
  animation-duration: 35s;
}

@keyframes wave {
  0% {
    transform: translateX(0);
  }
  100% {
    transform: translateX(-50%);
  }
}

.hero-container {
  max-width: 1400px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.hero-content {
  text-align: center;
  margin-bottom: 60px;
}

.hero-title {
  font-size: 56px;
  font-weight: 800;
  margin-bottom: 20px;
  text-shadow: 0 4px 20px rgba(0,0,0,0.3);
  animation: fadeInUp 0.8s ease-out;
}

.hero-subtitle {
  font-size: 24px;
  margin-bottom: 15px;
  opacity: 0.95;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-description {
  font-size: 16px;
  opacity: 0.9;
  margin-bottom: 40px;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

.hero-actions {
  display: flex;
  gap: 20px;
  justify-content: center;
  animation: fadeInUp 0.8s ease-out 0.6s both;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 16px 36px;
  font-size: 16px;
  font-weight: 600;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-primary {
  background: white;
  color: #0f4c75;
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 30px rgba(255,255,255,0.3);
}

.btn-outline {
  background: transparent;
  color: white;
  border: 2px solid white;
}

.btn-outline:hover {
  background: rgba(255,255,255,0.15);
  transform: translateY(-3px);
}

.btn-arrow {
  transition: transform 0.3s ease;
}

.btn:hover .btn-arrow {
  transform: translateX(5px);
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 30px;
  max-width: 1000px;
  margin: 0 auto;
}

.stat-card {
  background: rgba(255,255,255,0.15);
  backdrop-filter: blur(10px);
  padding: 30px;
  border-radius: 16px;
  display: flex;
  align-items: center;
  gap: 20px;
  transition: all 0.3s ease;
  animation: fadeInUp 0.8s ease-out 0.8s both;
}

.stat-card:hover {
  background: rgba(255,255,255,0.2);
  transform: translateY(-5px);
}

.stat-icon {
  font-size: 48px;
}

.stat-number {
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 5px;
}

.stat-label {
  font-size: 14px;
  opacity: 0.9;
}

/* 通用区块样式 */
.section {
  padding: 80px 20px;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-title-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 15px;
  margin-bottom: 15px;
}

.section-icon {
  font-size: 48px;
}

.section-title {
  font-size: 42px;
  font-weight: 700;
  color: #0f4c75;
}

.section-desc {
  font-size: 18px;
  color: #666;
  max-width: 600px;
  margin: 0 auto;
}

/* 分类区块 */
.categories-section {
  background: white;
}

.categories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 30px;
}

.category-item {
  background: white;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.08);
  transition: all 0.3s ease;
  cursor: pointer;
}

.category-item:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 40px rgba(15, 76, 117, 0.15);
}

.category-thumb {
  position: relative;
  height: 180px;
  background: linear-gradient(135deg, #3282b8 0%, #0f4c75 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.category-icon-large {
  font-size: 80px;
  filter: drop-shadow(0 4px 8px rgba(0,0,0,0.2));
}

.category-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.6), transparent);
  padding: 15px;
}

.category-count {
  color: white;
  font-size: 14px;
  font-weight: 600;
}

.category-content {
  padding: 25px;
}

.category-content h3 {
  font-size: 22px;
  color: #0f4c75;
  margin-bottom: 10px;
}

.category-content p {
  color: #666;
  font-size: 14px;
  margin-bottom: 15px;
  line-height: 1.6;
}

.category-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag {
  padding: 5px 12px;
  background: #e3f2fd;
  color: #1976d2;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
}

/* 热门榜单 */
.trending-section {
  background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
}

.trending-grid {
  display: grid;
  gap: 25px;
}

.trending-card {
  background: white;
  border-radius: 20px;
  padding: 30px;
  display: flex;
  gap: 25px;
  align-items: center;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.08);
  transition: all 0.3s ease;
}

.trending-card:hover {
  transform: translateX(10px);
  box-shadow: 0 8px 30px rgba(15, 76, 117, 0.15);
}

.trending-card.featured {
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 100%);
  color: white;
}

.trending-rank {
  font-size: 40px;
  font-weight: 700;
  color: #bbb;
  min-width: 60px;
  text-align: center;
}

.trending-rank.gold {
  color: #ffd700;
  text-shadow: 0 2px 10px rgba(255, 215, 0, 0.5);
}

.trending-rank.silver {
  color: #c0c0c0;
}

.trending-rank.bronze {
  color: #cd7f32;
}

.trending-thumbnail {
  position: relative;
  width: 140px;
  height: 105px;
  background: linear-gradient(135deg, #3282b8 0%, #0f4c75 100%);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.thumb-icon {
  font-size: 60px;
}

.thumb-badge {
  position: absolute;
  top: 8px;
  right: 8px;
  background: #ff4444;
  color: white;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
}

.trending-info {
  flex: 1;
}

.trending-title {
  font-size: 22px;
  margin-bottom: 12px;
  font-weight: 600;
}

.trending-card.featured .trending-title {
  color: white;
}

.trending-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: #888;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.trending-card.featured .trending-meta {
  color: rgba(255,255,255,0.9);
}

.meta-divider {
  color: #ccc;
}

.trending-desc {
  color: #666;
  font-size: 15px;
  line-height: 1.6;
  margin-bottom: 12px;
}

.trending-card.featured .trending-desc {
  color: rgba(255,255,255,0.95);
}

.trending-tags {
  display: flex;
  gap: 8px;
}

.tag-hot {
  padding: 5px 12px;
  background: rgba(255,255,255,0.2);
  color: white;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
}

/* 最新视频 */
.latest-section {
  background: white;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 30px;
}

.video-item {
  background: #f8fafc;
  border-radius: 16px;
  overflow: hidden;
  transition: all 0.3s ease;
  cursor: pointer;
}

.video-item:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 40px rgba(15, 76, 117, 0.15);
}

.video-cover {
  position: relative;
  height: 180px;
  background: linear-gradient(135deg, #3282b8 0%, #0f4c75 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.cover-icon {
  font-size: 70px;
}

.video-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  background: rgba(0,0,0,0.7);
  color: white;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 11px;
  font-weight: 600;
}

.video-time {
  position: absolute;
  bottom: 12px;
  right: 12px;
  background: rgba(0,0,0,0.8);
  color: white;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
}

.video-body {
  padding: 20px;
}

.video-title {
  font-size: 16px;
  font-weight: 600;
  color: #1a1a2e;
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-info {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.info-tag {
  padding: 4px 10px;
  background: #e3f2fd;
  color: #1976d2;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
}

.info-views {
  color: #888;
  font-size: 13px;
}

.video-date {
  color: #999;
  font-size: 12px;
}

/* 精选内容 */
.featured-section {
  background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
}

.featured-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 30px;
}

.featured-card {
  background: white;
  border-radius: 20px;
  padding: 30px;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.08);
  transition: all 0.3s ease;
  position: relative;
}

.featured-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 40px rgba(15, 76, 117, 0.15);
}

.featured-card.featured-large {
  grid-column: span 2;
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 100%);
  color: white;
}

.featured-badge {
  position: absolute;
  top: 20px;
  right: 20px;
  background: rgba(255,255,255,0.95);
  color: #0f4c75;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
}

.featured-thumb {
  margin-bottom: 20px;
}

.featured-icon {
  font-size: 60px;
}

.featured-content h3 {
  font-size: 24px;
  margin-bottom: 15px;
  font-weight: 600;
}

.featured-card.featured-large .featured-content h3 {
  color: white;
}

.featured-content p {
  font-size: 15px;
  line-height: 1.8;
  color: #666;
  margin-bottom: 20px;
}

.featured-card.featured-large .featured-content p {
  color: rgba(255,255,255,0.95);
}

.featured-meta {
  display: flex;
  gap: 15px;
  font-size: 14px;
  flex-wrap: wrap;
}

.meta-badge {
  padding: 6px 12px;
  background: rgba(255,255,255,0.2);
  color: white;
  border-radius: 8px;
  font-weight: 500;
}

.featured-card:not(.featured-large) .meta-badge {
  background: #e3f2fd;
  color: #1976d2;
}

.meta-views, .meta-rating {
  color: rgba(255,255,255,0.9);
}

.featured-card:not(.featured-large) .meta-views,
.featured-card:not(.featured-large) .meta-rating {
  color: #888;
}

/* 话题讨论 */
.topics-section {
  background: white;
}

.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(400px, 1fr));
  gap: 25px;
}

.topic-card {
  background: #f8fafc;
  border-radius: 16px;
  padding: 25px;
  transition: all 0.3s ease;
  cursor: pointer;
  border-left: 4px solid transparent;
}

.topic-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 30px rgba(15, 76, 117, 0.12);
  border-left-color: #3282b8;
}

.topic-card.hot {
  background: linear-gradient(135deg, #fff5f5 0%, #ffe6e6 100%);
  border-left-color: #ff4444;
}

.topic-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 15px;
}

.topic-user {
  display: flex;
  gap: 12px;
  align-items: center;
}

.user-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, #3282b8 0%, #0f4c75 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}

.user-details {
  display: flex;
  flex-direction: column;
}

.user-name {
  font-weight: 600;
  color: #1a1a2e;
  font-size: 14px;
}

.user-time {
  font-size: 12px;
  color: #888;
}

.topic-badge {
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  background: #e3f2fd;
  color: #1976d2;
}

.topic-badge.hot-badge {
  background: #ffebee;
  color: #c62828;
}

.topic-title {
  font-size: 18px;
  font-weight: 600;
  color: #1a1a2e;
  margin-bottom: 12px;
  line-height: 1.5;
}

.topic-content {
  color: #666;
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 15px;
}

.topic-images {
  display: flex;
  gap: 10px;
  margin-bottom: 15px;
}

.topic-img {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, #e0f2fe 0%, #bae6fd 100%);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
}

.topic-footer {
  display: flex;
  gap: 20px;
  font-size: 13px;
  color: #888;
}

/* 关于我们 */
.about-section {
  background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
}

.about-container {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 40px;
}

.about-card {
  background: white;
  padding: 40px;
  border-radius: 20px;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.08);
  margin-bottom: 30px;
}

.about-card h3 {
  font-size: 28px;
  color: #0f4c75;
  margin-bottom: 20px;
}

.about-card p {
  font-size: 16px;
  line-height: 1.8;
  color: #666;
  margin-bottom: 15px;
}

.about-features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.about-feature {
  background: white;
  padding: 25px;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.08);
  text-align: center;
  transition: all 0.3s ease;
}

.about-feature:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 30px rgba(15, 76, 117, 0.15);
}

.feature-icon-box {
  font-size: 48px;
  margin-bottom: 15px;
}

.about-feature h4 {
  font-size: 18px;
  color: #0f4c75;
  margin-bottom: 10px;
}

.about-feature p {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
}

.contact-card, .social-card {
  background: white;
  padding: 30px;
  border-radius: 20px;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.08);
  margin-bottom: 20px;
}

.contact-card h3, .social-card h3 {
  font-size: 22px;
  color: #0f4c75;
  margin-bottom: 20px;
}

.contact-list {
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 15px;
}

.contact-icon {
  font-size: 28px;
}

.contact-info {
  display: flex;
  flex-direction: column;
}

.contact-label {
  font-size: 12px;
  color: #888;
  margin-bottom: 2px;
}

.contact-value {
  font-size: 14px;
  color: #1a1a2e;
  font-weight: 500;
}

.social-links {
  display: grid;
  gap: 12px;
}

.social-link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  background: #f0f9ff;
  border-radius: 10px;
  text-decoration: none;
  color: #1a1a2e;
  transition: all 0.3s ease;
}

.social-link:hover {
  background: #e0f2fe;
  transform: translateX(5px);
}

.social-icon {
  font-size: 24px;
}

/* Footer */
.footer {
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 100%);
  color: white;
  padding: 60px 20px 30px;
}

.footer-container {
  max-width: 1400px;
  margin: 0 auto;
}

.footer-main {
  display: grid;
  grid-template-columns: 1.5fr 2fr;
  gap: 60px;
  margin-bottom: 40px;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 24px;
  font-weight: 700;
}

.footer-desc {
  font-size: 14px;
  opacity: 0.9;
  line-height: 1.6;
}

.footer-stats {
  display: flex;
  gap: 30px;
}

.footer-stat {
  display: flex;
  flex-direction: column;
}

.footer-stat strong {
  font-size: 20px;
  margin-bottom: 5px;
}

.footer-stat span {
  font-size: 12px;
  opacity: 0.8;
}

.footer-links-group {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

.footer-column h4 {
  font-size: 16px;
  margin-bottom: 15px;
  font-weight: 600;
}

.footer-column a {
  display: block;
  color: rgba(255,255,255,0.8);
  text-decoration: none;
  font-size: 14px;
  margin-bottom: 10px;
  transition: all 0.3s ease;
}

.footer-column a:hover {
  color: white;
  padding-left: 5px;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.2);
  padding-top: 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 20px;
}

.copyright {
  font-size: 14px;
  opacity: 0.9;
}

.footer-links-inline {
  display: flex;
  gap: 15px;
  font-size: 14px;
}

.footer-links-inline a {
  color: rgba(255,255,255,0.8);
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-links-inline a:hover {
  color: white;
}

/* 返回顶部按钮 */
.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 50px;
  height: 50px;
  background: linear-gradient(135deg, #0f4c75 0%, #1b6ca8 100%);
  color: white;
  border: none;
  border-radius: 50%;
  font-size: 24px;
  cursor: pointer;
  box-shadow: 0 4px 20px rgba(15, 76, 117, 0.3);
  transition: all 0.3s ease;
  z-index: 999;
  display: flex;
  align-items: center;
  justify-content: center;
}

.back-to-top:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 30px rgba(15, 76, 117, 0.4);
}

/* 动画效果 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    transform: translateY(-100%);
  }
  to {
    transform: translateY(0);
  }
}

@keyframes bounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-5px);
  }
}

/* 响应式设计 */
@media (max-width: 1200px) {
  .featured-card.featured-large {
    grid-column: span 1;
  }

  .about-container {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .header-container {
    flex-direction: column;
    height: auto;
    padding: 15px 20px;
    gap: 15px;
  }

  .nav {
    flex-wrap: wrap;
    justify-content: center;
  }

  .nav-link {
    padding: 8px 12px;
    font-size: 13px;
  }

  .hero-title {
    font-size: 36px;
  }

  .hero-subtitle {
    font-size: 18px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .section {
    padding: 50px 20px;
  }

  .section-title {
    font-size: 32px;
  }

  .categories-grid,
  .video-grid,
  .featured-grid,
  .topics-grid {
    grid-template-columns: 1fr;
  }

  .trending-card {
    flex-direction: column;
    text-align: center;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .footer-links-group {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

  .about-features-grid {
    grid-template-columns: 1fr;
  }
}