/* 智数站样式表 */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #7c3aed;
    --accent-color: #06b6d4;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --transition: all 0.3s ease;
}

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

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* 导航栏 */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 4rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-icon {
    font-size: 1.75rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

.nav-menu a.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--primary-color);
    border-radius: 1px;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* Hero 区域 */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 5rem 0;
    position: relative;
    overflow: hidden;
}

.hero::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='0.08'%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");
    opacity: 0.5;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1.5rem;
}

.gradient-text {
    background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 2rem;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    gap: 3rem;
    margin-bottom: 2.5rem;
}

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

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.stat-label {
    font-size: 0.875rem;
    opacity: 0.8;
}

.hero-cta {
    display: flex;
    gap: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 1.75rem;
    border-radius: var(--radius-lg);
    font-weight: 500;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

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

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

.btn-secondary {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.3);
}

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

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

/* 浮动卡片 */
.hero-visual {
    position: relative;
    height: 400px;
}

.floating-cards {
    position: relative;
    width: 100%;
    height: 100%;
}

.float-card {
    position: absolute;
    background: white;
    color: var(--text-primary);
    padding: 1rem 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    font-weight: 600;
    animation: float 3s ease-in-out infinite;
}

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

.card-2 {
    top: 30%;
    right: 5%;
    animation-delay: 0.5s;
}

.card-3 {
    bottom: 30%;
    left: 5%;
    animation-delay: 1s;
}

.card-4 {
    bottom: 10%;
    right: 15%;
    animation-delay: 1.5s;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

/* 区块标题 */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.125rem;
    margin-bottom: 3rem;
}

/* 分类区域 */
.categories {
    padding: 5rem 0;
    background: var(--bg-secondary);
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: var(--radius-xl);
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.category-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.category-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.category-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.category-card p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* 最新文章 */
.latest-articles {
    padding: 5rem 0;
}

.article-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.article-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

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

.article-tag {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.article-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    line-height: 1.4;
}

.article-card h3 a {
    color: var(--text-primary);
    text-decoration: none;
}

.article-card h3 a:hover {
    color: var(--primary-color);
}

.article-excerpt {
    color: var(--text-secondary);
    font-size: 0.9375rem;
    line-height: 1.7;
    margin-bottom: 1rem;
}

.article-meta {
    display: flex;
    gap: 1rem;
    color: var(--text-light);
    font-size: 0.875rem;
}

.view-more {
    text-align: center;
}

/* 特色服务 */
.features {
    padding: 5rem 0;
    background: var(--bg-secondary);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.feature-item {
    text-align: center;
    padding: 2rem;
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-item h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.feature-item p {
    color: var(--text-secondary);
}

/* 关于我们 */
.about {
    padding: 5rem 0;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    color: var(--text-secondary);
    font-size: 1.125rem;
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

/* 页脚 */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.footer-brand .logo-icon,
.footer-brand .logo-text {
    color: white;
}

.footer-brand p {
    color: var(--text-light);
    margin-top: 0.5rem;
}

.footer-links h4 {
    font-size: 1rem;
    margin-bottom: 1rem;
    color: white;
}

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

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: var(--text-light);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 2rem;
    text-align: center;
    color: var(--text-light);
    font-size: 0.875rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 4rem;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        box-shadow: var(--shadow-lg);
    }

    .nav-menu.active {
        display: flex;
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .hero-stats {
        justify-content: center;
    }

    .hero-visual {
        display: none;
    }

    .hero-cta {
        justify-content: center;
    }

    .section-title {
        font-size: 2rem;
    }

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

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

/* 文章页面样式 */
.page-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.page-header p {
    font-size: 1.125rem;
    opacity: 0.9;
}

.articles-list {
    padding: 3rem 0;
}

.articles-container {
    max-width: 900px;
    margin: 0 auto;
}

.article-full {
    background: white;
    border-radius: var(--radius-xl);
    padding: 2rem;
    margin-bottom: 2rem;
    border: 1px solid var(--border-color);
}

.article-full h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.article-full h2 a {
    color: var(--text-primary);
    text-decoration: none;
}

.article-full h2 a:hover {
    color: var(--primary-color);
}

.article-content-preview {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1rem;
}

.read-more {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.read-more:hover {
    text-decoration: underline;
}

/* 文章详情页 */
.article-detail {
    padding: 3rem 0;
}

.article-container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: var(--radius-xl);
    padding: 3rem;
    box-shadow: var(--shadow-md);
}

.article-header {
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
}

.article-header h1 {
    font-size: 2rem;
    line-height: 1.4;
    margin-bottom: 1rem;
}

.article-body {
    font-size: 1.0625rem;
    line-height: 1.9;
    color: var(--text-primary);
}

.article-body h2 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
    color: var(--text-primary);
}

.article-body h3 {
    font-size: 1.25rem;
    margin: 1.5rem 0 0.75rem;
    color: var(--text-primary);
}

.article-body p {
    margin-bottom: 1rem;
}

.article-body table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
}

.article-body th,
.article-body td {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    text-align: left;
}

.article-body th {
    background: var(--bg-secondary);
    font-weight: 600;
}

.article-body ul,
.article-body ol {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

.article-body li {
    margin-bottom: 0.5rem;
}

.back-link {
    display: inline-block;
    margin-top: 2rem;
    color: var(--primary-color);
    text-decoration: none;
}

.back-link:hover {
    text-decoration: underline;
}