/* ========================================
   CSS 变量定义
   ======================================== */
:root {
    /* 主色调 - 活力橙色系 */
    --primary-color: #FF6B6B;
    --primary-light: #FF8E8E;
    --primary-dark: #E85555;
    
    /* 辅助色 - 深青色 */
    --secondary-color: #4ECDC4;
    --secondary-light: #6FD9D1;
    --secondary-dark: #3BB5AD;
    
    /* 点缀色 - 黄绿色 */
    --accent-color: #FFE66D;
    --accent-light: #FFF19F;
    --accent-dark: #F5D742;
    
    /* 中性色 */
    --bg-color: #FFFBF5;
    --bg-secondary: #FFF5E8;
    --text-primary: #2D3748;
    --text-secondary: #718096;
    --text-light: #A0AEC0;
    --white: #FFFFFF;
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #FF6B6B 0%, #FFE66D 100%);
    --gradient-secondary: linear-gradient(135deg, #4ECDC4 0%, #44A3F7 100%);
    --gradient-hero: linear-gradient(135deg, rgba(255,107,107,0.1) 0%, rgba(255,230,109,0.1) 100%);
    
    /* 阴影 */
    --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);
    --shadow-xl: 0 16px 48px rgba(0,0,0,0.2);
    
    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;
    
    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;
    
    /* 过渡 */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s ease;
    --transition-slow: all 0.5s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', 'Poppins', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-color);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

@media (min-width: 768px) {
    .container {
        padding: 0 var(--spacing-lg);
    }
}

/* ========================================
   导航栏
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: var(--shadow-md);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.logo-icon {
    font-size: 1.5rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-md);
    align-items: center;
}

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    transition: var(--transition);
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 80%;
    height: 2px;
    background: var(--gradient-primary);
    transition: transform 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    transform: translateX(-50%) scaleX(1);
}

.btn-login {
    color: var(--text-secondary) !important;
}

/* 移动端菜单切换按钮 */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

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

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

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

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* 移动端导航菜单 */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: var(--white);
        flex-direction: column;
        padding: var(--spacing-xl) var(--spacing-md);
        gap: var(--spacing-md);
        transition: left 0.3s ease;
        box-shadow: var(--shadow-lg);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-link {
        width: 100%;
        text-align: center;
        padding: var(--spacing-md);
        font-size: 1.1rem;
    }
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    text-decoration: none;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
    border: 2px solid transparent;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
}

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

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

.btn-white:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-outline-white {
    background: transparent;
    color: var(--white);
    border-color: var(--white);
}

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

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

.btn-block {
    width: 100%;
}

/* ========================================
   Hero 区域
   ======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: -1;
}

.hero-gradient {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-hero);
}

.hero-shapes {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    overflow: hidden;
}

.shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.3;
    animation: float 20s infinite ease-in-out;
}

.shape-1 {
    width: 500px;
    height: 500px;
    background: var(--primary-color);
    top: -200px;
    right: -100px;
    animation-delay: 0s;
}

.shape-2 {
    width: 400px;
    height: 400px;
    background: var(--secondary-color);
    bottom: -150px;
    left: -100px;
    animation-delay: 5s;
}

.shape-3 {
    width: 300px;
    height: 300px;
    background: var(--accent-color);
    top: 50%;
    left: 50%;
    animation-delay: 10s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(50px, 50px); }
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
    align-items: center;
}

@media (min-width: 768px) {
    .hero-content {
        grid-template-columns: 1fr 1fr;
    }
}

.hero-text {
    animation: fadeInUp 1s ease;
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 4rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: var(--spacing-md);
    display: flex;
    flex-direction: column;
}

.title-line {
    display: block;
}

.highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 3vw, 1.3rem);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

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

.hero-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    padding-top: var(--spacing-xl);
    border-top: 2px solid rgba(0,0,0,0.05);
}

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

.stat-number {
    font-size: 2rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-top: var(--spacing-xs);
}

/* Hero 图片 */
.hero-image {
    position: relative;
    animation: fadeInRight 1s ease;
}

.image-wrapper {
    position: relative;
}

.image-placeholder {
    width: 100%;
    max-width: 500px;
    margin: 0 auto;
    animation: pulse 3s infinite ease-in-out;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.floating-badge {
    position: absolute;
    background: var(--white);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-lg);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    animation: floatBadge 3s infinite ease-in-out;
}

.badge-1 {
    top: 20%;
    left: -10%;
    animation-delay: 0s;
}

.badge-2 {
    bottom: 20%;
    right: -10%;
    animation-delay: 1.5s;
}

@keyframes floatBadge {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

/* 滚动指示器 */
.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--text-secondary);
    font-size: 0.9rem;
    animation: bounce 2s infinite;
}

.scroll-arrow {
    font-size: 1.5rem;
}

@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(10px); }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* ========================================
   Section 通用样式
   ======================================== */
section {
    padding: var(--spacing-3xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.section-label {
    display: inline-block;
    color: var(--primary-color);
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: var(--spacing-sm);
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ========================================
   课程卡片
   ======================================== */
.courses {
    background: var(--bg-secondary);
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
}

.course-card {
    background: var(--white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    position: relative;
}

.course-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.course-card.featured {
    border: 3px solid var(--primary-color);
}

.featured-badge {
    position: absolute;
    top: 20px;
    right: -35px;
    background: var(--gradient-primary);
    color: var(--white);
    padding: 0.5rem 3rem;
    transform: rotate(45deg);
    font-weight: 600;
    font-size: 0.85rem;
    z-index: 10;
    box-shadow: var(--shadow-md);
}

.course-image {
    position: relative;
    height: 250px;
    overflow: hidden;
}

.course-image-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

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

.course-emoji {
    font-size: 5rem;
}

.course-badge {
    position: absolute;
    top: var(--spacing-md);
    left: var(--spacing-md);
    background: rgba(255,255,255,0.95);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 600;
    box-shadow: var(--shadow-sm);
}

.course-content {
    padding: var(--spacing-xl);
}

.course-category {
    color: var(--primary-color);
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: var(--spacing-sm);
}

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

.course-description {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.course-features {
    list-style: none;
    margin-bottom: var(--spacing-xl);
}

.course-features li {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-xs) 0;
    color: var(--text-secondary);
}

.course-features li span {
    color: var(--secondary-color);
    font-weight: 700;
}

.course-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--spacing-md);
    border-top: 2px solid var(--bg-secondary);
}

.course-price {
    display: flex;
    align-items: baseline;
    gap: 0.25rem;
}

.price-label {
    font-size: 0.85rem;
    color: var(--text-light);
}

.price-value {
    font-size: 2rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.price-unit {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ========================================
   特色功能
   ======================================== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
}

.feature-item {
    text-align: center;
    padding: var(--spacing-xl);
    background: var(--white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

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

.feature-icon {
    font-size: 3.5rem;
    margin-bottom: var(--spacing-md);
}

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

.feature-description {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ========================================
   教练卡片
   ======================================== */
.coaches {
    background: var(--bg-secondary);
}

.coaches-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.coach-card {
    background: var(--white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

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

.coach-image {
    position: relative;
    height: 320px;
    overflow: hidden;
}

.coach-image-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.coach-card:hover .coach-image-placeholder {
    transform: scale(1.05);
}

.coach-social {
    position: absolute;
    bottom: var(--spacing-md);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: var(--spacing-sm);
    opacity: 0;
    transition: var(--transition);
}

.coach-card:hover .coach-social {
    opacity: 1;
}

.coach-social a {
    width: 40px;
    height: 40px;
    background: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    text-decoration: none;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.coach-social a:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.coach-info {
    padding: var(--spacing-xl);
    text-align: center;
}

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

.coach-title {
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.coach-description {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.coach-stats {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 2px solid var(--bg-secondary);
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ========================================
   学员评价
   ======================================== */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
}

.testimonial-card {
    background: var(--white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

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

.testimonial-rating {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-md);
}

.testimonial-text {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-xl);
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.author-avatar {
    width: 50px;
    height: 50px;
    background: var(--bg-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.author-name {
    font-weight: 700;
    margin-bottom: 0.25rem;
}

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

/* ========================================
   CTA 区域
   ======================================== */
.cta {
    position: relative;
    padding: var(--spacing-3xl) 0;
    overflow: hidden;
}

.cta-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: -1;
}

.cta-gradient {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-primary);
}

.cta-content {
    text-align: center;
    color: var(--white);
}

.cta-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.cta-subtitle {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-xl);
    opacity: 0.95;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
}

.cta-note {
    font-size: 0.95rem;
    opacity: 0.9;
}

/* ========================================
   联系我们
   ======================================== */
.contact {
    background: var(--bg-secondary);
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-2xl);
}

@media (min-width: 768px) {
    .contact-wrapper {
        grid-template-columns: 1fr 1.2fr;
    }
}

.contact-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.contact-description {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-xl);
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.contact-item {
    display: flex;
    gap: var(--spacing-md);
}

.contact-icon {
    font-size: 2rem;
    width: 50px;
    height: 50px;
    background: var(--white);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.contact-label {
    font-weight: 600;
    margin-bottom: 0.25rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.contact-value {
    color: var(--text-primary);
    font-size: 1.1rem;
}

/* 表单 */
.contact-form-wrapper {
    background: var(--white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.form-group label {
    font-weight: 600;
    color: var(--text-primary);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: var(--spacing-md);
    border: 2px solid var(--bg-secondary);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(255,107,107,0.1);
}

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

/* ========================================
   页脚
   ======================================== */
.footer {
    background: var(--text-primary);
    color: var(--white);
    padding: var(--spacing-3xl) 0 var(--spacing-xl) 0;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.footer-description {
    color: rgba(255,255,255,0.7);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.footer-social {
    display: flex;
    gap: var(--spacing-sm);
}

.footer-social a {
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    text-decoration: none;
    transition: var(--transition);
}

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

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

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--white);
    padding-left: var(--spacing-xs);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-xl);
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.5);
}

/* ========================================
   动画 - AOS (Animate On Scroll)
   ======================================== */
[data-aos] {
    opacity: 0;
    transition: opacity 0.8s ease, transform 0.8s ease;
}

[data-aos].aos-animate {
    opacity: 1;
}

[data-aos="fade-up"] {
    transform: translateY(30px);
}

[data-aos="fade-up"].aos-animate {
    transform: translateY(0);
}

[data-aos="zoom-in"] {
    transform: scale(0.9);
}

[data-aos="zoom-in"].aos-animate {
    transform: scale(1);
}

[data-aos="flip-left"] {
    transform: perspective(1000px) rotateY(-30deg);
}

[data-aos="flip-left"].aos-animate {
    transform: perspective(1000px) rotateY(0);
}

/* ========================================
   响应式优化
   ======================================== */
@media (max-width: 768px) {
    .hero {
        min-height: auto;
        padding: 100px 0 50px;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
    }
    
    .hero-image {
        order: -1;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .hero-buttons .btn {
        width: 100%;
    }
    
    .hero-stats {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .stat-number {
        font-size: 1.5rem;
    }
    
    .floating-badge {
        position: static;
        margin: var(--spacing-sm) auto;
        width: fit-content;
    }
    
    .course-grid,
    .coaches-grid,
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    section {
        padding: var(--spacing-2xl) 0;
    }
    
    .cta-buttons {
        flex-direction: column;
    }
    
    .cta-buttons .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.75rem;
    }
    
    .course-card,
    .testimonial-card {
        border-radius: var(--radius-md);
    }
}