/* 全局样式 */
:root {
    --primary-color: #2c3e50;
    --accent-color: #3498db;
    --accent-light: #5dade2;
    --text-color: #2c3e50;
    --text-light: #7f8c8d;
    --bg-color: #ffffff;
    --bg-light: #f8f9fa;
    --bg-dark: #1a1a2e;
    --border-color: #ecf0f1;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.12);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    /* 系统字体优先，避免等待Google Fonts */
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
    /* 防止页面加载时的布局抖动 */
    overflow-x: hidden;
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.05);
    transition: var(--transition);
    /* 性能优化：提示浏览器将要变化的属性 */
    will-change: background, box-shadow;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 700;
    font-size: 1.3rem;
}

.logo-icon {
    font-size: 1.8rem;
    color: var(--accent-color);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 35px;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    font-size: 0.95rem;
    position: relative;
    padding: 5px 0;
    transition: var(--transition);
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--accent-color);
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 2px;
    background: var(--text-color);
    transition: var(--transition);
}

/* 主横幅 */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    opacity: 0.9;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: white;
    padding: 20px;
}

.hero-title {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 15px;
    letter-spacing: 8px;
    text-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
    animation: fadeInUp 1s ease;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 20px;
    letter-spacing: 4px;
    animation: fadeInUp 1s ease 0.2s backwards;
}

.hero-desc {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 40px;
    animation: fadeInUp 1s ease 0.4s backwards;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    animation: fadeInUp 1s ease 0.6s backwards;
}

.btn {
    display: inline-block;
    padding: 14px 35px;
    border-radius: 50px;
    font-weight: 500;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

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

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

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

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

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-indicator span {
    display: block;
    width: 20px;
    height: 30px;
    border: 2px solid white;
    border-radius: 15px;
    position: relative;
}

.scroll-indicator span::before {
    content: '';
    position: absolute;
    top: 5px;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 8px;
    background: white;
    border-radius: 2px;
    animation: scroll 2s infinite;
}

/* 区块样式 */
.section {
    padding: 100px 0;
}

.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    color: var(--primary-color);
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: var(--accent-color);
    margin: 20px auto 0;
}

/* 核心理念 */
.concepts {
    background: var(--bg-light);
}

.concept-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.concept-card {
    background: white;
    padding: 40px 30px;
    border-radius: 15px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.concept-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.concept-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.concept-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* 主要业务 */
.business-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 40px;
}

.business-card {
    display: flex;
    gap: 30px;
    padding: 40px;
    background: white;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
    border: 1px solid var(--border-color);
}

.business-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
    border-color: var(--accent-color);
}

.business-icon {
    font-size: 3rem;
    flex-shrink: 0;
}

.business-content h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.business-content p {
    color: var(--text-light);
    margin-bottom: 15px;
    font-size: 0.95rem;
}

.business-link {
    color: var(--accent-color);
    font-weight: 500;
    font-size: 0.9rem;
}

/* 数据统计 */
.stats {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    text-align: center;
}

.stat-item {
    padding: 20px;
}

.stat-number {
    display: block;
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 10px;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
}

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

.article-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.article-image {
    height: 180px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
}

.article-content {
    padding: 25px;
}

.article-tag {
    display: inline-block;
    padding: 5px 12px;
    background: var(--bg-light);
    color: var(--accent-color);
    border-radius: 20px;
    font-size: 0.8rem;
    margin-bottom: 15px;
}

.article-title {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.article-excerpt {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 15px;
}

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

.section-footer {
    text-align: center;
    margin-top: 50px;
}

/* 页脚 */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 80px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 50px;
    margin-bottom: 50px;
}

.footer-brand .logo-icon {
    color: var(--accent-light);
}

.footer-brand p {
    margin-top: 15px;
    opacity: 0.7;
}

.footer-links h4,
.footer-contact h4 {
    font-size: 1.1rem;
    margin-bottom: 20px;
    color: white;
}

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

.footer-links li {
    margin-bottom: 12px;
}

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

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

.footer-contact p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 10px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.9rem;
}

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

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    40% {
        transform: translateX(-50%) translateY(-10px);
    }
    60% {
        transform: translateX(-50%) translateY(-5px);
    }
}

@keyframes scroll {
    0% {
        opacity: 1;
        top: 5px;
    }
    100% {
        opacity: 0;
        top: 15px;
    }
}

/* 响应式设计 */
@media (max-width: 992px) {
    .hero-title {
        font-size: 3rem;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 40px;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        gap: 15px;
        box-shadow: var(--shadow);
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 2.5rem;
        letter-spacing: 4px;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        gap: 15px;
    }
    
    .business-grid {
        grid-template-columns: 1fr;
    }
    
    .business-card {
        flex-direction: column;
        text-align: center;
    }
    
    .section {
        padding: 60px 0;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .stat-number {
        font-size: 2.5rem;
    }
}

/* 页面特定样式 */
.page-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 150px 0 80px;
    color: white;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.page-header p {
    opacity: 0.9;
    font-size: 1.1rem;
}

/* 文章列表页 */
.article-list {
    padding: 80px 0;
}

.article-group {
    margin-bottom: 60px;
}

.article-group h2 {
    font-size: 1.8rem;
    margin-bottom: 30px;
    padding-bottom: 15px;
    border-bottom: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 15px;
}

.article-group h2::before {
    content: '';
    width: 4px;
    height: 30px;
    background: var(--accent-color);
    border-radius: 2px;
}

.monthly-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
}

.monthly-item {
    background: white;
    border-radius: 10px;
    padding: 25px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
    border: 2px solid transparent;
}

.monthly-item:hover {
    transform: translateY(-5px);
    border-color: var(--accent-color);
}

.monthly-item .issue-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent-color);
    margin-bottom: 10px;
}

.monthly-item .issue-title {
    font-size: 1rem;
    color: var(--text-color);
}

/* 关于页面 */
.about-section {
    padding: 80px 0;
}

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

.about-text h2 {
    font-size: 2rem;
    margin-bottom: 20px;
    color: var(--primary-color);
}

.about-text p {
    color: var(--text-light);
    margin-bottom: 20px;
    font-size: 1.05rem;
}

.about-image {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 20px;
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 5rem;
}

/* 联系页面 */
.contact-section {
    padding: 80px 0;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-info h2 {
    font-size: 2rem;
    margin-bottom: 30px;
    color: var(--primary-color);
}

.contact-item {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
    padding: 25px;
    background: var(--bg-light);
    border-radius: 15px;
}

.contact-icon {
    font-size: 2rem;
}

.contact-details h3 {
    font-size: 1.1rem;
    margin-bottom: 5px;
}

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

.contact-form h2 {
    font-size: 2rem;
    margin-bottom: 30px;
    color: var(--primary-color);
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

/* 使命页面 */
.mission-section {
    padding: 80px 0;
}

.mission-block {
    margin-bottom: 80px;
}

.mission-block h2 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 15px;
}

.mission-block h2 .icon {
    font-size: 2rem;
}

.mission-block p {
    color: var(--text-light);
    font-size: 1.05rem;
    line-height: 1.8;
}

.mission-values {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.value-card {
    background: var(--bg-light);
    padding: 30px;
    border-radius: 15px;
    text-align: center;
}

.value-card .icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.value-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.value-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* 服务人群页面 */
.audience-section {
    padding: 80px 0;
}

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

.audience-card {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.audience-card:hover {
    transform: translateY(-5px);
    border-color: var(--accent-color);
}

.audience-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.audience-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--primary-color);
}

.audience-card p {
    color: var(--text-light);
    margin-bottom: 15px;
}

.audience-card ul {
    list-style: none;
}

.audience-card li {
    padding: 8px 0;
    color: var(--text-light);
    position: relative;
    padding-left: 20px;
}

.audience-card li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent-color);
}