/* 武汉易考复读学校 - 主样式文件 */
/* 基础样式重置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: #333;
  background-color: #fff;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease;
}

ul, ol {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* CSS变量定义 */
:root {
  --primary-color: #1a5fb4;
  --primary-dark: #0d3a7d;
  --primary-light: #3584e4;
  --secondary-color: #26a269;
  --accent-color: #e5a50a;
  --text-primary: #1c1c1c;
  --text-secondary: #5e5c64;
  --text-muted: #77767b;
  --bg-light: #fafafa;
  --bg-gray: #f0f0f0;
  --border-color: #deddda;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.16);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --transition: all 0.3s ease;
}

/* 容器 */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ========== 页头样式 ========== */
.header {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  color: #fff;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  box-shadow: var(--shadow-md);
}

.header-top {
  background: rgba(0, 0, 0, 0.15);
  padding: 8px 0;
  font-size: 13px;
}

.header-top .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.header-top-left {
  display: flex;
  align-items: center;
  gap: 20px;
}

.header-top-left i {
  margin-right: 5px;
}

.header-main {
  padding: 15px 0;
}

.header-main .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

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

.logo-icon {
  width: 50px;
  height: 50px;
  background: var(--accent-color);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: bold;
  color: var(--primary-dark);
}

.logo-text h1 {
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 2px;
}

.logo-text p {
  font-size: 12px;
  opacity: 0.85;
}

/* 导航菜单 */
.nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  gap: 5px;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 12px 20px;
  font-size: 15px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.9);
  border-radius: var(--radius-md);
  transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 10px;
  cursor: pointer;
  background: none;
  border: none;
}

.menu-toggle span {
  width: 25px;
  height: 3px;
  background: #fff;
  border-radius: 2px;
  transition: var(--transition);
}

/* ========== 页脚样式 ========== */
.footer {
  background: linear-gradient(135deg, var(--primary-dark) 0%, #0a2647 100%);
  color: #fff;
  padding: 50px 0 0;
}

.footer-main {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-section h3 {
  font-size: 18px;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 10px;
}

.footer-section h3::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 3px;
  background: var(--accent-color);
  border-radius: 2px;
}

.footer-section p {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 10px;
}

.footer-section ul li {
  margin-bottom: 10px;
}

.footer-section ul li a {
  color: rgba(255, 255, 255, 0.8);
  font-size: 14px;
  transition: var(--transition);
}

.footer-section ul li a:hover {
  color: var(--accent-color);
  padding-left: 5px;
}

.footer-contact i {
  margin-right: 8px;
  color: var(--accent-color);
}

.footer-bottom {
  padding: 20px 0;
  text-align: center;
}

.footer-info {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 10px;
}

.footer-info span {
  margin: 0 15px;
}

.footer-copyright {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
}

.footer-icp {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.4);
  margin-top: 8px;
}

.footer-icp a {
  color: rgba(255, 255, 255, 0.5);
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-icp a:hover {
  color: var(--accent-color);
}

.footer-icp span {
  margin: 0 8px;
}

/* ========== 主内容区域 ========== */
.main-content {
  margin-top: 120px;
  min-height: calc(100vh - 400px);
}

/* ========== Banner轮播 ========== */
.banner {
  position: relative;
  height: 500px;
  overflow: hidden;
}

.banner-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  transition: opacity 0.8s ease;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

/* 使用CSS渐变背景作为fallback，确保即使图片加载失败也能正常显示 */
.banner-slide:nth-child(1) {
  background: linear-gradient(135deg, #1a5fb4 0%, #0d3a7d 50%, #1a5fb4 100%);
}

.banner-slide:nth-child(2) {
  background: linear-gradient(135deg, #0d3a7d 0%, #1a5fb4 50%, #26a269 100%);
}

.banner-slide:nth-child(3) {
  background: linear-gradient(135deg, #1a5fb4 0%, #3584e4 50%, #0d3a7d 100%);
}

.banner-slide.active {
  opacity: 1;
}

.banner-slide img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: absolute;
  top: 0;
  left: 0;
}

.banner-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(to right, rgba(26, 95, 180, 0.85), rgba(26, 95, 180, 0.4));
  display: flex;
  align-items: center;
}

.banner-content {
  color: #fff;
  max-width: 600px;
  padding: 0 50px;
}

.banner-content h2 {
  font-size: 42px;
  margin-bottom: 20px;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.banner-content p {
  font-size: 18px;
  margin-bottom: 30px;
  opacity: 0.95;
}

.banner-dots {
  position: absolute;
  bottom: 30px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 10px;
}

.banner-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.5);
  cursor: pointer;
  transition: var(--transition);
}

.banner-dot.active {
  background: #fff;
  width: 30px;
  border-radius: 6px;
}

/* ========== 按钮样式 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 30px;
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition);
  border: none;
  gap: 8px;
}

.btn-primary {
  background: var(--accent-color);
  color: var(--primary-dark);
}

.btn-primary:hover {
  background: #f5b82e;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

.btn-outline:hover {
  background: #fff;
  color: var(--primary-color);
}

.btn-secondary {
  background: var(--primary-color);
  color: #fff;
}

.btn-secondary:hover {
  background: var(--primary-dark);
}

/* ========== 区块标题 ========== */
.section {
  padding: 80px 0;
}

.section-gray {
  background: var(--bg-light);
}

.section-header {
  text-align: center;
  margin-bottom: 50px;
}

.section-title {
  font-size: 32px;
  color: var(--text-primary);
  margin-bottom: 15px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
  border-radius: 2px;
}

.section-subtitle {
  font-size: 16px;
  color: var(--text-muted);
  margin-top: 20px;
}

/* ========== 特色模块 ========== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
}

.feature-card {
  background: #fff;
  padding: 40px 30px;
  border-radius: var(--radius-lg);
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-lg);
}

.feature-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 25px;
  background: linear-gradient(135deg, var(--primary-light), var(--primary-color));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 36px;
  color: #fff;
}

.feature-card h3 {
  font-size: 20px;
  color: var(--text-primary);
  margin-bottom: 15px;
}

.feature-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ========== 统计数据 ========== */
.stats {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  padding: 60px 0;
  color: #fff;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 30px;
  text-align: center;
}

.stat-item h3 {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--accent-color);
}

.stat-item p {
  font-size: 16px;
  opacity: 0.9;
}

/* ========== 卡片网格 ========== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 30px;
}

.card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.card-image {
  height: 200px;
  overflow: hidden;
}

.card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.card:hover .card-image img {
  transform: scale(1.1);
}

.card-body {
  padding: 25px;
}

.card-title {
  font-size: 18px;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.card-text {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
}

.card-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 15px;
  padding-top: 15px;
  border-top: 1px solid var(--border-color);
  font-size: 13px;
  color: var(--text-muted);
}

/* ========== 新闻列表 ========== */
.news-list {
  display: flex;
  flex-direction: column;
  gap: 25px;
}

.news-item {
  display: flex;
  gap: 25px;
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.news-item:hover {
  box-shadow: var(--shadow-md);
}

.news-image {
  flex-shrink: 0;
  width: 280px;
  height: 180px;
}

.news-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.news-content {
  flex: 1;
  padding: 20px 25px 20px 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.news-title {
  font-size: 18px;
  color: var(--text-primary);
  margin-bottom: 12px;
  line-height: 1.5;
}

.news-title:hover {
  color: var(--primary-color);
}

.news-excerpt {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 15px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.news-date {
  font-size: 13px;
  color: var(--text-muted);
}

/* ========== 图片展示 ========== */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.gallery-item {
  position: relative;
  height: 220px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  cursor: pointer;
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.gallery-item:hover img {
  transform: scale(1.1);
}

.gallery-overlay {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 20px;
  background: linear-gradient(transparent, rgba(0, 0, 0, 0.7));
  color: #fff;
  transform: translateY(100%);
  transition: var(--transition);
}

.gallery-item:hover .gallery-overlay {
  transform: translateY(0);
}

/* ========== 案例展示 ========== */
.case-card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.case-header {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 25px;
  background: linear-gradient(135deg, var(--primary-light), var(--primary-color));
  color: #fff;
}

.case-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  overflow: hidden;
  border: 3px solid #fff;
}

.case-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.case-info h3 {
  font-size: 20px;
  margin-bottom: 5px;
}

.case-info p {
  opacity: 0.9;
  font-size: 14px;
}

.case-body {
  padding: 25px;
}

.case-stats {
  display: flex;
  justify-content: space-around;
  margin-bottom: 20px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.case-stat {
  text-align: center;
}

.case-stat h4 {
  font-size: 28px;
  color: var(--primary-color);
  margin-bottom: 5px;
}

.case-stat p {
  font-size: 13px;
  color: var(--text-muted);
}

.case-story {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.9;
}

/* ========== 表单样式 ========== */
.form-group {
  margin-bottom: 20px;
}

.form-label {
  display: block;
  margin-bottom: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
}

.form-label.required::after {
  content: '*';
  color: #e74c3c;
  margin-left: 4px;
}

.form-control {
  width: 100%;
  padding: 12px 16px;
  font-size: 14px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: var(--transition);
  background: #fff;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(26, 95, 180, 0.1);
}

.form-control::placeholder {
  color: var(--text-muted);
}

textarea.form-control {
  min-height: 120px;
  resize: vertical;
}

/* ========== 联系信息 ========== */
.contact-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 50px;
}

.contact-info {
  padding: 40px;
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: #fff;
  border-radius: var(--radius-lg);
}

.contact-info h3 {
  font-size: 24px;
  margin-bottom: 30px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 15px;
  margin-bottom: 25px;
}

.contact-item i {
  font-size: 20px;
  color: var(--accent-color);
  margin-top: 3px;
}

.contact-item h4 {
  font-size: 16px;
  margin-bottom: 5px;
}

.contact-item p {
  font-size: 14px;
  opacity: 0.9;
}

.contact-form {
  padding: 40px;
  background: #fff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

/* ========== 关于我们页面 ========== */
.about-hero {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: #fff;
  padding: 80px 0;
  text-align: center;
}

.about-hero h1 {
  font-size: 36px;
  margin-bottom: 15px;
}

.about-hero p {
  font-size: 18px;
  opacity: 0.9;
}

.about-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-text h2 {
  font-size: 28px;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.about-text p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 2;
  margin-bottom: 15px;
}

.about-image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

/* ========== 师资团队 ========== */
.team-stats {
  display: flex;
  justify-content: center;
  gap: 60px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.team-stat-item {
  text-align: center;
}

.team-stat-num {
  display: block;
  font-size: 36px;
  font-weight: 700;
  color: var(--primary-color);
  line-height: 1.2;
}

.team-stat-label {
  display: block;
  font-size: 14px;
  color: var(--text-secondary);
  margin-top: 5px;
}

.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 30px;
}

.team-card {
  background: #fff;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: var(--transition);
}

.team-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.team-photo {
  height: 280px;
  overflow: hidden;
}

.team-photo img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.team-info {
  padding: 25px;
}

.team-name {
  font-size: 20px;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.team-title {
  font-size: 14px;
  color: var(--primary-color);
  margin-bottom: 15px;
}

.team-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ========== 面包屑导航 ========== */
.breadcrumb {
  background: linear-gradient(135deg, rgba(26, 95, 180, 0.08) 0%, rgba(13, 58, 125, 0.12) 100%);
  padding: 15px 0;
  font-size: 14px;
  border-bottom: 1px solid rgba(26, 95, 180, 0.15);
}

.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 10px;
}

.breadcrumb-item a {
  color: var(--primary-color);
  transition: color 0.3s ease;
}

.breadcrumb-item a:hover {
  color: var(--primary-dark);
}

.breadcrumb-item.active {
  color: var(--text-primary);
  font-weight: 500;
}

.breadcrumb-separator {
  color: var(--primary-light);
  opacity: 0.6;
}

/* ========== 响应式设计 ========== */
@media (max-width: 992px) {
  .header-main .container {
    flex-wrap: wrap;
  }

  .nav {
    position: fixed;
    top: 120px;
    left: 0;
    right: 0;
    background: var(--primary-dark);
    padding: 20px;
    transform: translateY(-150%);
    transition: transform 0.3s ease;
    box-shadow: var(--shadow-lg);
  }

  .nav.active {
    transform: translateY(0);
  }

  .nav-list {
    flex-direction: column;
  }

  .nav-link {
    padding: 15px 20px;
  }

  .menu-toggle {
    display: flex;
  }

  .banner {
    height: 400px;
  }

  .banner-content h2 {
    font-size: 32px;
  }

  .about-content,
  .contact-section {
    grid-template-columns: 1fr;
  }

  .news-item {
    flex-direction: column;
  }

  .news-image {
    width: 100%;
    height: 200px;
  }

  .news-content {
    padding: 20px;
  }
}

@media (max-width: 768px) {
  .header-top {
    display: none;
  }

  .header-main {
    padding: 12px 0;
  }

  .logo-icon {
    width: 40px;
    height: 40px;
    font-size: 18px;
  }

  .logo-text h1 {
    font-size: 18px;
  }

  .logo-text p {
    font-size: 11px;
  }

  .main-content {
    margin-top: 70px;
  }

  .banner {
    height: 350px;
  }

  .banner-content {
    padding: 0 25px;
  }

  .banner-content h2 {
    font-size: 26px;
  }

  .banner-content p {
    font-size: 15px;
  }

  .section {
    padding: 50px 0;
  }

  .section-title {
    font-size: 26px;
  }

  .stat-item h3 {
    font-size: 36px;
  }

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

  .footer-info span {
    display: block;
    margin: 5px 0;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }

  .banner {
    height: 300px;
  }

  .banner-content h2 {
    font-size: 22px;
  }

  .btn {
    padding: 10px 20px;
    font-size: 14px;
  }

  .feature-card {
    padding: 30px 20px;
  }

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

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

/* ========== Layui样式覆盖 ========== */
.layui-tab {
  margin: 0;
}

.layui-tab-title {
  border-bottom: 2px solid var(--border-color);
}

.layui-tab-title li {
  margin: 0 15px;
  padding: 0 5px;
  line-height: 50px;
}

.layui-tab-title .layui-this {
  color: var(--primary-color);
  border-bottom: 2px solid var(--primary-color);
}

.layui-form-label {
  width: 100px;
}

.layui-layer {
  border-radius: var(--radius-lg) !important;
}

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

.animate-fadeInUp {
  animation: fadeInUp 0.6s ease forwards;
}

/* ========== 懒加载图片 ========== */
.lazy-image {
  opacity: 0;
  transition: opacity 0.3s ease;
}

.lazy-image.loaded {
  opacity: 1;
}

/* ========== 空状态 ========== */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-muted);
}

.empty-state i {
  font-size: 64px;
  margin-bottom: 20px;
  opacity: 0.5;
}

.empty-state p {
  font-size: 16px;
}

/* ========== 加载状态 ========== */
.loading {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 40px;
}

.loading-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border-color);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* ========== 返回顶部按钮 ========== */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  background: var(--primary-color);
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
  box-shadow: var(--shadow-md);
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: var(--primary-dark);
  transform: translateY(-5px);
}

/* ========== 页面内导航高亮 ========== */
.page-nav {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.page-nav .btn {
  min-width: 140px;
}

.page-nav .btn.active {
  background: var(--primary-color);
  color: #fff;
}