/* 公共样式 - 老宝贝陪诊网站 */
:root {
    /* 颜色系统 */
    --primary-color: #3B82F6;
    --secondary-color: #10B981;
    --accent-color: #F59E0B;
    --danger-color: #EF4444;
    --warning-color: #F59E0B;
    --success-color: #10B981;
    --text-dark: #1F2937;
    --text-light: #6B7280;
    --bg-light: #F9FAFB;
    --white: #FFFFFF;
    
    /* 阴影系统 */
    --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.05);
    --shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 25px 50px rgba(0, 0, 0, 0.2);
    
    /* 渐变系统 */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-accent: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-card: linear-gradient(135deg, rgba(255, 255, 255, 0.9), rgba(255, 255, 255, 0.7));
    
    /* 流体尺寸系统 */
    --container-fluid: min(95vw, 1400px);
    --container-lg: min(90vw, 1200px);
    --container-md: min(85vw, 1000px);
    --container-sm: min(80vw, 800px);
    
    /* 间距系统 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* 边框圆角系统 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    
    /* 过渡动画 */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

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

/* 确保最小字体大小 */
* {
    font-size: clamp(18px, 1rem, 24px);
}

/* 允许特定元素覆盖最小字体大小 */
h1, h2, h3, h4, h5, h6, .service-icon, .hero-icon, .stat-number {
    font-size: revert;
}

/* body 使用固定最小字体 */
body {
    font-size: 18px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: hidden;
    background: var(--bg-light);
    font-size: 18px;
}

/* 流体容器系统 */
.fluid-container {
    width: var(--container-fluid);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.container-lg {
    width: var(--container-lg);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

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

.container-sm {
    width: var(--container-sm);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* 现代网格系统 */
.grid {
    display: grid;
    gap: var(--spacing-lg);
    transition: gap var(--transition-base);
}

.grid-fluid {
    display: grid;
    gap: var(--spacing-lg);
    grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
}

.grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
    grid-template-columns: repeat(4, 1fr);
}

.grid-auto {
    grid-template-columns: repeat(auto-fit, minmax(min(280px, 100%), 1fr));
}

/* Flexbox 系统 */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-center {
    align-items: center;
    justify-content: center;
}

.flex-between {
    justify-content: space-between;
}

.flex-around {
    justify-content: space-around;
}

.flex-1 {
    flex: 1;
}

/* 流体卡片系统 */
.fluid-card {
    background: var(--white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow);
    padding: var(--spacing-xl);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.8);
    font-size: 18px;
}

.fluid-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.fluid-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.fluid-card:hover::before {
    opacity: 1;
}

.fluid-card-glass {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.fluid-card-gradient {
    background: var(--gradient-card);
    color: var(--text-dark);
}

/* 按钮系统 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-full);
    font-weight: 600;
    text-decoration: none;
    transition: all var(--transition-base);
    cursor: pointer;
    border: none;
    position: relative;
    overflow: hidden;
    font-size: 20px;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width var(--transition-slow), height var(--transition-slow);
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn-primary {
    background: var(--primary-color);
    color: var(--white);
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
}

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

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

/* 微交互效果 */
.interactive {
    transition: all var(--transition-base);
    cursor: pointer;
}

.interactive:hover {
    transform: translateY(-2px);
}

.interactive:active {
    transform: translateY(0) scale(0.98);
}

/* 脉冲动画 */
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

.pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* 漂浮动画 */
@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

.float {
    animation: float 3s ease-in-out infinite;
}

/* 响应式断点系统 */
/* 超小屏 (0-575px) */
@media (max-width: 575px) {
    :root {
        --container-fluid: 100vw;
        --container-lg: 95vw;
        --container-md: 90vw;
        --container-sm: 85vw;
        --spacing-lg: 1rem;
        --spacing-xl: 1.5rem;
    }
    
    .grid-fluid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .fluid-card {
        padding: var(--spacing-lg);
    }
    
    .btn {
        padding: var(--spacing-sm) var(--spacing-lg);
    }
}

/* 小屏 (576px-767px) */
@media (min-width: 576px) and (max-width: 767px) {
    :root {
        --container-fluid: min(95vw, 1200px);
        --container-lg: min(90vw, 1100px);
        --container-md: min(85vw, 1000px);
        --container-sm: min(80vw, 900px);
    }
    
    .grid-3,
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content,
    .footer-container {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 中屏 (768px-1023px) */
@media (min-width: 768px) and (max-width: 1023px) {
    :root {
        --container-fluid: min(90vw, 1300px);
        --container-lg: min(85vw, 1200px);
        --container-md: min(80vw, 1100px);
        --container-sm: min(75vw, 1000px);
    }
    
    .grid-4 {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .footer-content,
    .footer-container {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* 大屏 (1024px-1439px) */
@media (min-width: 1024px) and (max-width: 1439px) {
    :root {
        --container-fluid: min(85vw, 1400px);
        --container-lg: min(80vw, 1300px);
        --container-md: min(75vw, 1200px);
        --container-sm: min(70vw, 1100px);
        --spacing-lg: 1.5rem;
        --spacing-xl: 2.5rem;
    }
    
    .footer-content,
    .footer-container {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* 超大屏 (1440px+) */
@media (min-width: 1440px) and (max-width: 1919px) {
    :root {
        --container-fluid: min(80vw, 1600px);
        --container-lg: min(75vw, 1400px);
        --container-md: min(70vw, 1200px);
        --container-sm: min(65vw, 1000px);
        --spacing-lg: 2rem;
        --spacing-xl: 3rem;
        --spacing-2xl: 4rem;
    }
    
    .grid-auto {
        grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    }
    
    .footer-content,
    .footer-container {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* 4K+ 超大屏 (1920px+) */
@media (min-width: 1920px) {
    :root {
        --container-fluid: min(75vw, 1800px);
        --container-lg: min(70vw, 1600px);
        --container-md: min(65vw, 1400px);
        --container-sm: min(60vw, 1200px);
        --spacing-lg: 2.5rem;
        --spacing-xl: 4rem;
        --spacing-2xl: 5rem;
    }
    
    .grid-auto {
        grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    }
    
    .fluid-card {
        padding: var(--spacing-2xl);
    }
    
    .footer-content,
    .footer-container {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* 高宽比优化 */
@media (orientation: landscape) and (max-height: 600px) {
    .fluid-card {
        padding: var(--spacing-lg) var(--spacing-xl);
    }
}

@media (orientation: portrait) {
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: all var(--transition-base);
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    font-size: 18px;
}

.nav-container {
    width: var(--container-fluid);
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 var(--spacing-lg);
}

.logo {
    display: flex;
    align-items: center;
    font-size: 28px;
    font-weight: bold;
    color: var(--text-dark);
    text-decoration: none;
    transition: transform 0.3s ease;
}

.logo:hover {
    transform: scale(1.05);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
    padding: 0.5rem 0;
    font-size: 18px;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.contact-btn {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
    font-size: 18px;
}

.contact-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

/* 移动端菜单 */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--primary-color);
}

/* 流体容器 */
.services-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* 响应式容器最大宽度 */
@media (min-width: 1919px) and (max-width: 1919px) {
    .services-container {
        max-width: 1919px;
    }
}

@media (min-width: 1440px) and (max-width: 1919px) {
    .services-container {
        max-width: 1300px;
        padding: 0 2.5rem;
    }
}

@media (min-width: 1920px) {
    .services-container {
        max-width: 1400px;
        padding: 0 3rem;
    }
}

@media (min-width: 2560px) {
    .services-container {
        max-width: 1600px;
        padding: 0 4rem;
    }
}

/* 通用卡片样式 */
.service-card,
.about-card,
.news-card,
.faq-item {
    background: white;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    overflow: hidden;
    font-size: 18px;
}

.service-card:hover,
.about-card:hover,
.news-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

/* 按钮样式 */
.btn-primary,
.btn-secondary,
.btn-outline {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    text-align: center;
    font-size: 20px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    box-shadow: 0 10px 25px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 35px rgba(59, 130, 246, 0.4);
}

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

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

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

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

/* 标题样式 */
.section-title {
    font-size: 2.5rem;
    font-weight: bold;
    color: var(--text-dark);
    margin-bottom: 1rem;
    text-align: center;
}

.section-subtitle {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-bottom: 3rem;
    text-align: center;
}

/* 页脚样式 */
.footer {
    background: linear-gradient(135deg, #1a1a1a, #2d2d2d);
    color: white;
    padding: 4rem 0 2rem;
    margin-top: 6rem;
    position: relative;
    overflow: hidden;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--primary-color), transparent);
    animation: footerShine 3s ease-in-out infinite;
}

@keyframes footerShine {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.8; }
}

.footer-content,
.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 3rem;
    padding: 0 2rem;
    position: relative;
    z-index: 1;
}

.footer-section h3 {
    font-size: 24px;
    margin-bottom: 1.5rem;
    color: white;
    font-weight: 700;
    position: relative;
    padding-bottom: 0.5rem;
}

.footer-section h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 2px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 1px;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.8;
    margin-bottom: 1rem;
    font-size: 18px;
}

.footer-section a {
    display: block;
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    margin-bottom: 0.75rem;
    transition: all 0.3s ease;
    padding: 0.25rem 0;
    border-radius: 4px;
    position: relative;
    font-size: 18px;
}

.footer-section a:hover {
    color: var(--primary-color);
    transform: translateX(8px);
    background: rgba(59, 130, 246, 0.1);
    padding-left: 0.5rem;
}

.footer-section a::before {
    content: '▸';
    position: absolute;
    left: -15px;
    opacity: 0;
    transition: all 0.3s ease;
    color: var(--primary-color);
}

.footer-section a:hover::before {
    opacity: 1;
    left: -5px;
}

.footer-bottom {
    text-align: center;
    padding: 2rem 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    margin-top: 3rem;
    color: rgba(255, 255, 255, 0.6);
    position: relative;
    z-index: 1;
}

.footer-bottom p {
    margin: 0;
    font-size: 18px;
}

/* 社交媒体链接 */
.footer-social {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.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;
    transition: all 0.3s ease;
    color: white;
    text-decoration: none;
}

.footer-social a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(59, 130, 246, 0.4);
}

/* 联系信息样式 */
.footer-contact {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.footer-contact .contact-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: rgba(255, 255, 255, 0.8);
}

.footer-contact .contact-item:hover {
    color: var(--primary-color);
    transform: translateX(5px);
}

/* 页脚徽章 */
.footer-badges {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

.footer-badge {
    background: rgba(59, 130, 246, 0.2);
    color: var(--primary-color);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    border: 1px solid rgba(59, 130, 246, 0.3);
}

/* 动画效果 */
.fade-in-section {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease;
}

.fade-in-section.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 流体布局优化 - 超大屏幕 */
@media (min-width: 1920px) {
    .nav-container {
        max-width: 1400px;
        padding: 0 3rem;
    }
    
    .services-container {
        max-width: 1400px;
        padding: 0 3rem;
    }
    
    .footer-content,
    .footer-container {
        max-width: 1400px;
        gap: 4rem;
        padding: 0 3rem;
    }
    
    .stats-container {
        max-width: 1400px;
    }
    
.service-icon {
    width: 100px;
    height: 100px;
    font-size: 48px;
}
    
    .section-title {
        font-size: 3rem;
    }
}

/* 大屏幕优化 */
@media (min-width: 1440px) and (max-width: 1919px) {
    .nav-container {
        max-width: 1300px;
    }
    
    .services-container {
        max-width: 1300px;
    }
    
    .footer-content {
        max-width: 1300px;
    }
}

/* 中大屏幕优化 */
@media (min-width: 1200px) and (max-width: 1439px) {
    .nav-container {
        max-width: 1200px;
    }
    
    .services-container {
        max-width: 1200px;
    }
    
    .footer-content {
        max-width: 1200px;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 2rem;
        box-shadow: var(--shadow-lg);
        border-radius: 0 0 20px 20px;
    }

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

    .mobile-menu-btn {
        display: block;
    }

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

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

    .btn-primary,
    .btn-secondary,
    .btn-outline {
        padding: 0.875rem 1.75rem;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    .section-title {
        font-size: 1.75rem;
    }

    .nav-container {
        padding: 0 1rem;
    }

    .services-container {
        padding: 0 1rem;
    }
}

/* 服务图标样式 */
.service-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 40px;
    transition: transform 0.3s ease;
}

.service-card:hover .service-icon {
    transform: scale(1.1) rotate(5deg);
}

/* 面包屑导航 */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
    padding: 1rem;
    background: var(--bg-light);
    border-radius: 10px;
}

.breadcrumb-item {
    color: var(--text-light);
}

.breadcrumb-item a {
    color: var(--primary-color);
    text-decoration: none;
}

.breadcrumb-item a:hover {
    text-decoration: underline;
}

/* 统计数据样式 */
.stats {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 4rem 2rem;
}

.stats-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

.stat-item {
    transition: transform 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-10px);
}

.stat-number {
    font-size: 3rem;
    font-weight: bold;
    margin-bottom: 0.5rem;
    display: block;
}

.stat-label {
    font-size: 1.1rem;
    opacity: 0.9;
}


/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
    box-shadow: var(--shadow);
    font-size: 1.2rem;
}

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

.back-to-top:hover {
    transform: translateY(-5px) rotate(360deg);
    box-shadow: var(--shadow-lg);
}

/* 流体间距控制 */
section {
    padding: 6rem 2rem;
}

@media (min-width: 1440px) {
    section {
        padding: 8rem 2rem;
    }
}

@media (min-width: 1920px) {
    section {
        padding: 10rem 2rem;
    }
}

/* 文本样式 */
h1, h2, h3, h4, h5, h6 {
    margin-bottom: 1rem;
    line-height: 1.2;
}

h1 {
    font-size: clamp(32px, 5vw, 48px);
}

h2 {
    font-size: clamp(28px, 4vw, 38px);
}

h3 {
    font-size: clamp(24px, 3vw, 32px);
}

h4 {
    font-size: clamp(20px, 2.5vw, 26px);
}

h5 {
    font-size: clamp(18px, 2vw, 22px);
}

h6 {
    font-size: clamp(18px, 1.8vw, 20px);
}

p {
    margin-bottom: 1rem;
    font-size: 18px;
}

a {
    color: var(--primary-color);
    transition: color 0.3s ease;
}

a:hover {
    color: var(--secondary-color);
}

/* 列表样式 */
ul, ol {
    margin-bottom: 1.5rem;
    padding-left: 2rem;
}

li {
    margin-bottom: 0.5rem;
    font-size: 18px;
}

/* 表单样式 */
input, textarea, select {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e5e7eb;
    border-radius: 10px;
    font-size: 18px;
    transition: border-color 0.3s ease;
    margin-bottom: 1rem;
}

input:focus, textarea:focus, select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* 流体网格布局 */
.grid {
    display: grid;
    gap: 2rem;
}

.grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
}

.grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
}

.grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

/* 超大屏幕网格优化 */
@media (min-width: 1920px) {
    .grid {
        gap: 3rem;
    }
    
    .grid-2 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .grid-3 {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .grid-4 {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* 大屏幕网格优化 */
@media (min-width: 1440px) and (max-width: 1919px) {
    .grid-2 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .grid-3 {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* 文本对齐 */
.text-center {
    text-align: center;
}

.text-left {
    text-align: left;
}

.text-right {
    text-align: right;
}

/* 边距工具类 */
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mt-3 { margin-top: 3rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }
.p-1 { padding: 1rem; }
.p-2 { padding: 2rem; }
.p-3 { padding: 3rem; }

/* 隐藏元素 */
.hidden {
    display: none;
}

/* 显示元素 */
.show {
    display: block;
}

/* 过渡效果 */
.transition {
    transition: all 0.3s ease;
}

/* 阴影效果 */
.shadow {
    box-shadow: var(--shadow);
}

.shadow-lg {
    box-shadow: var(--shadow-lg);
}