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

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #64748b;
    --accent-color: #06b6d4;
    --background-light: #f8fafc;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --white: #ffffff;
}

body {
    font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
}

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

/* 导航栏 */
.navbar {
    background-color: var(--white);
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s;
}

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

.btn-login {
    background-color: var(--primary-color);
    color: var(--white) !important;
    padding: 8px 20px;
    border-radius: 6px;
    transition: background-color 0.3s;
}

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

/* Hero部分 */
.hero {
    height: 100vh;
    background: linear-gradient(rgba(0,0,0,0.6), rgba(0,0,0,0.6)), url('../images/hero-bg.jpg');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    text-align: center;
    color: var(--white);
    margin-top: 70px;
    position: relative;
}

.hero-content {
    width: 100%;
    padding: 0 20px;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 56px;
    margin-bottom: 20px;
    line-height: 1.2;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.hero p {
    font-size: 24px;
    margin-bottom: 40px;
    opacity: 0.9;
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
}

.cta-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-top: 30px;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 15px 35px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s;
    font-size: 18px;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

.btn-secondary:hover {
    background-color: var(--white);
    color: var(--text-dark);
    transform: translateY(-2px);
}

.btn-outline {
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    background: transparent;
}

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

.btn-large {
    padding: 18px 40px;
    font-size: 20px;
}

/* AI特色部分 */
.ai-features {
    padding: 100px 0;
    background-color: var(--background-light);
}

.ai-features h2 {
    text-align: center;
    font-size: 42px;
    margin-bottom: 60px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card {
    text-align: center;
    padding: 40px;
    background: var(--white);
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-10px);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 24px;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.feature-card p {
    color: var(--text-light);
    font-size: 16px;
}

/* 用户分类 */
.user-types {
    padding: 100px 0;
}

.user-types h2 {
    text-align: center;
    font-size: 42px;
    margin-bottom: 60px;
}

.type-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.type-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.type-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.type-card h3 {
    font-size: 24px;
    padding: 20px;
    margin: 0;
    color: var(--primary-color);
}

.type-card ul {
    list-style: none;
    padding: 0 20px;
    margin-bottom: 20px;
}

.type-card li {
    padding: 10px 0;
    color: var(--text-light);
    border-bottom: 1px solid #e2e8f0;
}

.type-card li:last-child {
    border-bottom: none;
}

.type-card .btn {
    margin: 20px;
}

/* AI演示部分 */
.ai-demo {
    padding: 100px 0;
    background-color: var(--background-light);
}

.ai-demo h2 {
    text-align: center;
    font-size: 42px;
    margin-bottom: 60px;
}

.demo-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 40px;
    align-items: center;
}

.demo-video {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.demo-video video {
    width: 100%;
    display: block;
}

.demo-features {
    display: grid;
    gap: 30px;
}

.demo-feature {
    padding: 20px;
    background: var(--white);
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.demo-feature h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

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

/* 社区预览 */
.community-preview {
    padding: 100px 0;
}

.community-preview h2 {
    text-align: center;
    font-size: 42px;
    margin-bottom: 60px;
}

.community-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.community-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.user-story {
    display: flex;
    align-items: center;
    padding: 30px;
}

.story-image {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    margin-right: 20px;
}

.story-content h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.community-stats {
    padding: 60px 0;
    background-color: var(--background-light);
    display: flex;
    justify-content: center;
}

.stats-grid {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin: 3rem 0;
    text-align: center;
    max-width: 1000px;
}

.stat-item h3 {
    font-size: 36px;
    color: var(--primary-color);
    margin-bottom: 10px;
}

/* 开始使用 */
.get-started {
    padding: 100px 0;
    background-color: var(--background-light);
    text-align: center;
}

.get-started h2 {
    font-size: 42px;
    margin-bottom: 60px;
}

.start-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

.step {
    background: var(--white);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.step-number {
    width: 50px;
    height: 50px;
    background-color: var(--primary-color);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: bold;
    margin: 0 auto 20px;
}

/* 页脚 */
.footer {
    background-color: var(--text-dark);
    color: var(--white);
    padding: 80px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 18px;
    margin-bottom: 20px;
}

.footer-section ul {
    list-style: none;
    padding: 0;
}

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

.footer-section a {
    color: var(--white);
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s;
}

.footer-section a:hover {
    opacity: 1;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-link {
    color: var(--white);
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s;
}

.social-link:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
    opacity: 0.8;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hero {
        margin-top: 60px;
        height: auto;
        min-height: 100vh;
        padding: 60px 0;
    }
    
    .hero h1 {
        font-size: 36px;
    }
    
    .hero p {
        font-size: 18px;
    }
    
    .cta-buttons {
        flex-direction: column;
        gap: 15px;
    }
    
    .demo-content {
        grid-template-columns: 1fr;
    }
    
    .community-grid {
        grid-template-columns: 1fr;
    }
    
    .user-story {
        flex-direction: column;
        text-align: center;
    }
    
    .story-image {
        margin: 0 0 20px 0;
    }
    
    .community-stats {
        grid-template-columns: 1fr;
    }
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-content {
    animation: fadeIn 1s ease-out;
}

.feature-card {
    animation: fadeIn 0.5s ease-out;
    animation-fill-mode: both;
}

.feature-card:nth-child(2) {
    animation-delay: 0.2s;
}

.feature-card:nth-child(3) {
    animation-delay: 0.4s;
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--background-light);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}

/* 页面标题 */
.page-header {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 100px 0 60px;
    text-align: center;
    margin-top: 70px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.page-header .container {
    max-width: 800px;
    margin: 0 auto;
}

.page-header h1 {
    font-size: 48px;
    margin-bottom: 20px;
}

.page-header p {
    font-size: 20px;
    opacity: 0.8;
}

/* 训练计划页面 */
.filters {
    padding: 40px 0;
    background-color: var(--background-light);
}

.filter-options {
    display: flex;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 8px 20px;
    border: 2px solid var(--primary-color);
    border-radius: 30px;
    background: transparent;
    color: var(--primary-color);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
}

.filter-btn:hover,
.filter-btn.active {
    background-color: var(--primary-color);
    color: var(--white);
}

.program-list {
    padding: 60px 0;
}

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

.program-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.program-card:hover {
    transform: translateY(-5px);
}

.program-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
}

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

.program-card h3 {
    padding: 20px 20px 10px;
    color: var(--primary-color);
}

.program-card p {
    padding: 0 20px;
    color: var(--text-light);
}

.program-features {
    list-style: none;
    padding: 20px;
    margin: 0;
}

.program-features li {
    padding: 10px 0;
    color: var(--text-light);
    border-bottom: 1px solid #e2e8f0;
}

.program-features li:last-child {
    border-bottom: none;
}

.program-card .price {
    padding: 20px;
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-color);
}

.program-card .btn {
    margin: 20px;
    display: block;
    text-align: center;
}

/* 社区页面 */
.community-stats {
    padding: 60px 0;
    background-color: var(--background-light);
}

.stats-grid {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin: 3rem 0;
    text-align: center;
}

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

.stat-item h3 {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-item p {
    font-size: 1.2rem;
    color: var(--text-color);
}

.user-stories {
    padding: 60px 0;
}

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

.story-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.story-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.story-content {
    padding: 20px;
}

.story-content h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.story-time {
    color: var(--text-light);
    margin-bottom: 10px;
}

.story-text {
    color: var(--text-dark);
    line-height: 1.6;
}

.community-events {
    padding: 60px 0;
    background-color: var(--background-light);
}

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

.event-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    display: flex;
}

.event-date {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 20px;
    text-align: center;
    min-width: 100px;
}

.event-date .day {
    font-size: 36px;
    font-weight: bold;
    display: block;
}

.event-date .month {
    font-size: 16px;
}

.event-content {
    padding: 20px;
    flex: 1;
}

.event-content h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.event-content p {
    color: var(--text-light);
    margin-bottom: 20px;
}

/* 知识库页面 */
.knowledge-categories {
    padding: 60px 0;
}

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

.category-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.category-card:hover {
    transform: translateY(-5px);
}

.category-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.category-card h3 {
    padding: 20px 20px 10px;
    color: var(--primary-color);
}

.category-card p {
    padding: 0 20px 20px;
    color: var(--text-light);
}

.category-card .btn {
    margin: 0 20px 20px;
}

.popular-articles {
    padding: 60px 0;
    background-color: var(--background-light);
}

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

.article-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.article-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.article-content {
    padding: 20px;
}

.article-content h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.article-meta {
    color: var(--text-light);
    margin-bottom: 10px;
    font-size: 14px;
}

.article-excerpt {
    color: var(--text-dark);
    margin-bottom: 20px;
    line-height: 1.6;
}

/* 登录页面 */
.login-section {
    padding: 100px 0;
    min-height: calc(100vh - 70px);
    display: flex;
    align-items: center;
    background-color: var(--background-light);
}

.login-container {
    max-width: 400px;
    margin: 0 auto;
    background: var(--white);
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.login-container h2 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 30px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-dark);
}

.form-group input {
    width: 100%;
    padding: 12px;
    border: 1px solid #e2e8f0;
    border-radius: 6px;
    font-size: 16px;
}

.form-options {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.remember-me {
    display: flex;
    align-items: center;
    gap: 8px;
}

.forgot-password {
    color: var(--primary-color);
    text-decoration: none;
}

.btn-block {
    width: 100%;
    padding: 12px;
}

.login-divider {
    text-align: center;
    margin: 30px 0;
    position: relative;
}

.login-divider::before,
.login-divider::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 45%;
    height: 1px;
    background-color: #e2e8f0;
}

.login-divider::before {
    left: 0;
}

.login-divider::after {
    right: 0;
}

.login-divider span {
    background: var(--white);
    padding: 0 10px;
    color: var(--text-light);
}

.social-login {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.btn-social {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background: var(--white);
    border: 1px solid #e2e8f0;
    color: var(--text-dark);
}

.btn-social img {
    width: 24px;
    height: 24px;
}

.register-link {
    text-align: center;
    margin-top: 20px;
    color: var(--text-light);
}

.register-link a {
    color: var(--primary-color);
    text-decoration: none;
}

/* 响应式设计补充 */
@media (max-width: 768px) {
    .page-header {
        padding: 80px 0 40px;
    }
    
    .page-header h1 {
        font-size: 36px;
    }
    
    .page-header p {
        font-size: 18px;
    }
    
    .filter-options {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-btn {
        width: 100%;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .event-card {
        flex-direction: column;
    }
    
    .event-date {
        min-width: 100%;
        padding: 10px;
    }
    
    .login-container {
        padding: 30px 20px;
    }
}