/* 金乌编程网站样式表 */

/* ===== 基础样式 ===== */
:root {
  /* 主题颜色 - 亮色模式 */
  --primary-color: #ff6b35;
  --primary-light: #ff8a5c;
  --primary-dark: #e85a2a;
  --secondary-color: #2ec4b6;
  --accent-color: #ffca3a;
  --text-color: #333333;
  --text-light: #666666;
  --background-primary: #ffffff;
  --background-secondary: #f8f9fa;
  --background-tertiary: #edf2f7;
  --border-color: #e2e8f0;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --success-color: #48bb78;
  --error-color: #e53e3e;
  --warning-color: #f6ad55;
  --info-color: #4299e1;
  
  /* 字体 - 使用系统默认字体 */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
  
  /* 间距 */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-xxl: 3rem;
  
  /* 边框 */
  --border-radius-sm: 0.25rem;
  --border-radius-md: 0.5rem;
  --border-radius-lg: 1rem;
  --border-radius-full: 9999px;
  
  /* 过渡 */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* 容器宽度 */
  --container-max-width: 1200px;
}

/* 暗色模式 */
[data-theme="dark"] {
  --primary-color: #ff6b35;
  --primary-light: #ff8a5c;
  --primary-dark: #e85a2a;
  --secondary-color: #2ec4b6;
  --accent-color: #ffca3a;
  --text-color: #f7fafc;
  --text-light: #cbd5e0;
  --background-primary: #1a202c;
  --background-secondary: #2d3748;
  --background-tertiary: #4a5568;
  --border-color: #4a5568;
  --shadow-color: rgba(0, 0, 0, 0.3);
}

/* 重置样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  color: var(--text-color);
  background-color: var(--background-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

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

ul, ol {
  list-style: none;
}

button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

/* ===== 布局 ===== */
.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-xxl);
}

.section-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 100px;
  height: 4px;
  background: var(--primary-color);
  border-radius: var(--border-radius-full);
}

.section-description {
  font-size: 1.1rem;
  color: var(--text-light);
  max-width: 700px;
  margin: 0 auto;
}

/* ===== 主题切换 ===== */
#theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 1000;
  width: 40px;
  height: 40px;
  border-radius: var(--border-radius-full);
  background-color: var(--background-secondary);
  box-shadow: 0 2px 10px var(--shadow-color);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition-fast);
}

#theme-toggle:hover {
  background-color: var(--background-tertiary);
}

#theme-toggle i {
  font-size: 1.5rem;
  color: var(--text-color);
}

#light-icon {
  display: none;
}

#dark-icon {
  display: block;
}

[data-theme="dark"] #light-icon {
  display: block;
}

[data-theme="dark"] #dark-icon {
  display: none;
}

/* ===== 导航栏 ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background-color: var(--background-primary);
  box-shadow: 0 2px 10px var(--shadow-color);
  transition: background-color var(--transition-normal), box-shadow var(--transition-normal);
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

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

.logo a {
  display: flex;
  align-items: center;
  color: var(--text-color);
}

.logo-image {
  width: 40px;
  height: 40px;
  margin-right: var(--spacing-sm);
}

.logo-text {
  font-size: 1.5rem;
  font-weight: 700;
}

.nav-list {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-link {
  color: var(--text-color);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--border-radius-md);
  transition: all var(--transition-fast);
}

.nav-link:hover, .nav-link.active {
  color: var(--primary-color);
  background-color: var(--background-secondary);
}

.nav-link.highlight {
  color: white;
  background-color: var(--primary-color);
}

.nav-link.highlight:hover {
  background-color: var(--primary-dark);
}

.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 30px;
  height: 20px;
}

.bar {
  height: 3px;
  width: 100%;
  background-color: var(--text-color);
  border-radius: var(--border-radius-full);
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* 移动端菜单激活状态 */
.mobile-menu-toggle.active .bar:nth-child(1) {
  transform: translateY(8.5px) rotate(45deg);
}

.mobile-menu-toggle.active .bar:nth-child(2) {
  opacity: 0;
}

.mobile-menu-toggle.active .bar:nth-child(3) {
  transform: translateY(-8.5px) rotate(-45deg);
}

.nav.active {
  display: block;
  position: absolute;
  top: 80px;
  left: 0;
  width: 100%;
  background-color: var(--background-primary);
  box-shadow: 0 5px 10px var(--shadow-color);
  padding: var(--spacing-lg);
  z-index: 99;
}

.nav.active .nav-list {
  flex-direction: column;
  gap: var(--spacing-md);
}

.nav.active .nav-link {
  display: block;
  padding: var(--spacing-md);
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: var(--border-radius-md);
  font-weight: 500;
  transition: all var(--transition-fast);
  text-align: center;
}

.btn i {
  margin-right: var(--spacing-sm);
  font-size: 1.2em;
}

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

.btn-primary:hover {
  background-color: var(--primary-dark);
  color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(255, 107, 53, 0.3);
}

.btn-secondary {
  background-color: var(--background-secondary);
  color: var(--text-color);
}

.btn-secondary:hover {
  background-color: var(--background-tertiary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px var(--shadow-color);
}

.btn-cta {
  background-color: white;
  color: var(--primary-color);
  font-size: 1.1rem;
  padding: 1rem 2rem;
  border: 2px solid transparent;
  transition: all var(--transition-fast);
}

.btn-cta:hover {
  background-color: transparent;
  color: white;
  border-color: white;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(255, 255, 255, 0.2);
}

/* ===== 英雄区域 ===== */
.hero {
  padding: 160px 0 0;
  position: relative;
  overflow: hidden;
  background-color: var(--background-primary);
}

.hero .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-xxl);
  position: relative;
  z-index: 5;
  padding-bottom: 80px;
}

.hero-content {
  flex: 1;
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-lg);
}

.gradient-text {
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  
}
/*规则定义了一个名为 glowing 的动画，在动画的不同阶段（0%、50%、100%），text-shadow 的模糊半径有所变化。*/
@keyframes glowing {
  0% {
      text-shadow: 0 0 5px rgb(113, 195, 240), 0 0 20px rgb(76, 182, 248), 0 0 30px rgb(46, 164, 249);
  }
  50% {
      text-shadow: 0 0 10px rgb(59, 200, 247), 0 0 30px rgb(37, 176, 240), 0 0 40px rgb(48, 208, 244);
  }
  100% {
      text-shadow: 0 0 5px rgb(64, 123, 251), 0 0 20px rgb(35, 124, 249), 0 0 30px rgb(39, 130, 243);
  }
} 

.solid-text {
  font-family: 'Open Sans', sans-serif;
  color: #131616; /* 黑色 */
  font-weight: 700;
   /* 设置 text-shadow 属性，实现淡光特效.*/
   /*text-shadow: h-shadow v-shadow blur-radius color;，其中 h-shadow 是水平偏移量，v-shadow 是垂直偏移量，blur-radius 是模糊半径，color 是阴影颜色。*/
   text-shadow: 0 0 3px rgb(40, 101, 105), 0 0 0px rgb(33, 156, 227), 0 0 0px rgb(25, 137, 212);
   /*背景光闪烁特效*/
   /*animation: glowing 1.5s ease-in-out infinite alternate;*/
} 

.hero-description {
  font-size: 1.2rem;
  margin-bottom: var(--spacing-xl);
  color: var(--text-light);
  max-width: 600px;
}

.hero-buttons {
  display: flex;
  gap: var(--spacing-md);
}

.hero-image {
  flex: 1;
  display: flex;
  justify-content: center;
}

/* 新的分隔符样式 */
.hero-divider {
  position: relative;
  height: 100px;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  margin-top: -50px;
  z-index: 2;
  overflow: hidden;
}

.hero-divider::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 1200 120' preserveAspectRatio='none'%3E%3Cpath d='M0,60 L1200,60 L1200,120 C1000,80 800,100 600,90 C400,80 200,20 0,120 L0,60 Z' fill='white' opacity='0.3'%3E%3C/path%3E%3Cpath d='M0,60 L1200,60 L1200,100 C1050,60 850,80 650,70 C450,60 250,10 0,100 L0,60 Z' fill='white' opacity='0.6'%3E%3C/path%3E%3C/svg%3E");
  background-size: 100% 100%;
  background-position: bottom;
}

/* 浮动动画 */
.floating {
  animation: floating 3s ease-in-out infinite;
}

@keyframes floating {
  0% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-20px);
  }
  100% {
    transform: translateY(0px);
  }
}

/* ===== 数据统计 ===== */
.stats {
  padding: var(--spacing-xxl) 0;
  background-color: var(--background-secondary);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-xl);
}

.stat-item {
  text-align: center;
  padding: var(--spacing-lg);
  background-color: var(--background-primary);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 4px 20px var(--shadow-color);
  transition: transform var(--transition-fast);
}

.stat-item:hover {
  transform: translateY(-5px);
}

.stat-icon {
  font-size: 2.5rem;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.stat-number {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
  color: var(--text-color);
}

.stat-label {
  font-size: 1rem;
  color: var(--text-light);
}

/* ===== 课程体系 ===== */
.courses {
  padding: var(--spacing-xxl) 0;
}

.courses-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-xl);
}

.course-card {
  background-color: var(--background-primary);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-xl);
  box-shadow: 0 4px 20px var(--shadow-color);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.course-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.course-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 10px 30px var(--shadow-color);
}

.course-icon {
  font-size: 2.5rem;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.course-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.course-age {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: var(--spacing-md);
}

.course-description {
  margin-bottom: var(--spacing-lg);
  color: var(--text-light);
}

.course-link {
  display: inline-flex;
  align-items: center;
  font-weight: 500;
  color: var(--primary-color);
}

.course-link i {
  margin-left: var(--spacing-xs);
  transition: transform var(--transition-fast);
}

.course-link:hover i {
  transform: translateX(5px);
}

/* ===== 产品特色 ===== */
.features {
  padding: var(--spacing-xxl) 0;
  background-color: var(--background-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-xl);
}

.feature-item {
  background-color: var(--background-primary);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-xl);
  box-shadow: 0 4px 20px var(--shadow-color);
  transition: transform var(--transition-fast);
}

.feature-item:hover {
  transform: translateY(-5px);
}

.feature-icon {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.feature-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
}

.feature-description {
  color: var(--text-light);
}

/* ===== 少儿编程好处 ===== */
.benefits {
  padding: var(--spacing-xxl) 0;
  position: relative;
  background-color: var(--background-secondary);
  margin-top: 0;
}

.benefits-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-xl);
}

.benefit-item {
  background-color: var(--background-primary);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-xl);
  box-shadow: 0 4px 20px var(--shadow-color);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
  border-left: 4px solid var(--primary-color);
}

.benefit-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px var(--shadow-color);
}

.benefit-icon {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.benefit-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
}

.benefit-description {
  color: var(--text-light);
}

/* ===== 学习路径 ===== */
.learning-path {
  padding: var(--spacing-xxl) 0;
}

.path-timeline {
  position: relative;
  max-width: 800px;
  margin: 0 auto;
}

.path-timeline::before {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  left: 20px;
  width: 4px;
  background-color: var(--primary-light);
  border-radius: var(--border-radius-full);
}

.path-item {
  position: relative;
  padding-left: 60px;
  margin-bottom: var(--spacing-xl);
}

.path-icon {
  position: absolute;
  left: 0;
  top: 0;
  width: 40px;
  height: 40px;
  background-color: var(--primary-color);
  border-radius: var(--border-radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.2rem;
  z-index: 1;
}

.path-title {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
}

.path-description {
  color: var(--text-light);
}

/* 媒体查询 - 学习路径响应式 */
@media (max-width: 768px) {
  .path-timeline::before {
    left: 15px;
  }
  
  .path-item {
    padding-left: 50px;
  }
  
  .path-icon {
    width: 30px;
    height: 30px;
    font-size: 1rem;
  }
}

@media (max-width: 576px) {
  .path-timeline {
    padding-left: var(--spacing-sm);
  }
  
  .path-item {
    padding-left: 40px;
  }
}

/* ===== 用户评价 ===== */
.testimonials {
  padding: var(--spacing-xxl) 0;
  background-color: var(--background-secondary);
}

.testimonials-slider {
  display: flex;
  overflow-x: hidden;
  scroll-snap-type: x mandatory;
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

.testimonial-card {
  flex: 0 0 100%;
  scroll-snap-align: start;
  padding: var(--spacing-xl);
  background-color: var(--background-primary);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 4px 20px var(--shadow-color);
  margin-right: var(--spacing-xl);
}

.testimonial-content {
  margin-bottom: var(--spacing-lg);
}

.testimonial-text {
  font-size: 1.1rem;
  font-style: italic;
  color: var(--text-color);
  line-height: 1.8;
}

.testimonial-author {
  display: flex;
  align-items: center;
}

.testimonial-avatar {
  width: 60px;
  height: 60px;
  border-radius: var(--border-radius-full);
  object-fit: cover;
  margin-right: var(--spacing-md);
}

.testimonial-name {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.testimonial-role {
  font-size: 0.9rem;
  color: var(--text-light);
}

.testimonials-dots {
  display: flex;
  justify-content: center;
  margin-top: var(--spacing-xl);
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: var(--border-radius-full);
  background-color: var(--border-color);
  margin: 0 var(--spacing-xs);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.dot.active {
  background-color: var(--primary-color);
}

/* ===== 关于我们 ===== */
.about {
  padding: var(--spacing-xxl) 0;
}

.about-content {
  display: flex;
  align-items: center;
  gap: var(--spacing-xxl);
}

.about-text {
  flex: 1;
}

.about-description {
  margin-bottom: var(--spacing-lg);
  color: var(--text-light);
}

.about-values {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.value-item {
  text-align: center;
}

.value-icon {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.value-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
}

.value-description {
  font-size: 0.9rem;
  color: var(--text-light);
}

.about-image {
  flex: 1;
  display: flex;
  justify-content: center;
}

/* ===== 联系我们 ===== */
.contact {
  padding: var(--spacing-xxl) 0;
  background-color: var(--background-secondary);
}

.contact-content {
  display: flex;
  gap: var(--spacing-xxl);
}

.contact-info {
  flex: 1;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  margin-bottom: var(--spacing-lg);
}

.contact-icon {
  font-size: 1.5rem;
  color: var(--primary-color);
  margin-right: var(--spacing-md);
  margin-top: var(--spacing-xs);
}

.contact-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.contact-detail {
  color: var(--text-light);
}

.contact-qrcode {
  margin-top: var(--spacing-xl);
  text-align: center;
}

.contact-qrcode img {
  width: 150px;
  height: 150px;
  border-radius: var(--border-radius-md);
  margin-bottom: var(--spacing-sm);
}

.contact-form {
  flex: 1;
}

.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-group label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
}

.form-group textarea {
  width: 100%;
  padding: var(--spacing-sm);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  background-color: var(--background-primary);
  transition: border-color var(--transition-fast);
  resize: vertical;
  max-height: 100px;
  min-height: 60px;
  line-height: 1.2;
}

.form-group input {
  width: 100%;
  padding: var(--spacing-md);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-md);
  background-color: var(--background-primary);
  transition: border-color var(--transition-fast);
  height: 40px;
}

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

/* ===== 行动召唤 ===== */
.cta {
  padding: var(--spacing-xl) 0;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  text-align: center;
  position: relative;
}

.cta-content {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-lg) 0;
}

.cta-title {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  color: white;
}

.cta-description {
  font-size: 1.2rem;
  margin-bottom: var(--spacing-xl);
  color: rgba(255, 255, 255, 0.9);
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

/* ===== 页脚 ===== */
.footer {
  background-color: var(--background-tertiary);
  padding-top: var(--spacing-xxl);
  color: var(--text-color);
}

.footer-top {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-xxl);
  margin-bottom: var(--spacing-xxl);
}

.footer-logo {
  display: flex;
  align-items: center;
  margin-bottom: var(--spacing-lg);
}

.footer-nav {
  display: flex;
  flex: 1;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--spacing-xl);
}

.footer-nav-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: var(--spacing-lg);
}

.footer-nav-list li {
  margin-bottom: var(--spacing-md);
}

.footer-nav-list a {
  color: var(--text-light);
  transition: color var(--transition-fast);
}

.footer-nav-list a:hover {
  color: var(--primary-color);
}

.social-links {
  display: flex;
  gap: var(--spacing-md);
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--border-radius-full);
  background-color: var(--background-secondary);
  color: var(--text-color);
  font-size: 1.2rem;
  transition: all var(--transition-fast);
}

.social-link:hover {
  background-color: var(--primary-color);
  color: white;
  transform: translateY(-3px);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-lg) 0;
  border-top: 1px solid var(--border-color);
}

.copyright {
  font-size: 0.9rem;
  color: var(--text-light);
}

.footer-links {
  display: flex;
  gap: var(--spacing-lg);
}

.footer-links a {
  font-size: 0.9rem;
  color: var(--text-light);
}

/* ===== 返回顶部按钮 ===== */
#back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 50px;
  height: 50px;
  border-radius: var(--border-radius-full);
  background-color: var(--primary-color);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  z-index: 99;
  box-shadow: 0 4px 12px rgba(255, 107, 53, 0.3);
}

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

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

/* ===== 响应式设计 ===== */
@media (max-width: 1200px) {
  .hero-title {
    font-size: 3rem;
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .courses-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .benefits-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 992px) {
  .hero .container {
    flex-direction: column;
    text-align: center;
  }
  
  .hero-description {
    margin-left: auto;
    margin-right: auto;
  }
  
  .hero-buttons {
    justify-content: center;
  }
  
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .about-content {
    flex-direction: column;
  }
  
  .contact-content {
    flex-direction: column;
  }
}

@media (max-width: 768px) {
  .nav {
    display: none;
  }
  
  .mobile-menu-toggle {
    display: flex;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .courses-grid,
  .features-grid,
  .benefits-grid {
    grid-template-columns: 1fr;
  }
  
  .about-values {
    grid-template-columns: 1fr;
  }
  
  .footer-top {
    flex-direction: column;
  }
  
  .footer-nav {
    flex-direction: column;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--spacing-md);
  }
}

@media (max-width: 576px) {
  .hero-title {
    font-size: 2.5rem;
  }
  
  .hero-buttons {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .testimonial-author {
    flex-direction: column;
    text-align: center;
  }
  
  .testimonial-avatar {
    margin-right: 0;
    margin-bottom: var(--spacing-sm);
  }
}

/* 导航链接下划线效果 */
.nav-links .nav-link {
  position: relative;
}

.nav-links .nav-link:not(.highlight):not(.active)::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--primary-color);
  transition: var(--transition-normal);
}

.nav-links .nav-link:not(.highlight):not(.active):hover::after {
  width: 60%;
}

/* 高亮按钮不显示下划线 */
.nav-links .nav-link.highlight::after {
  display: none;
}