/* ========================================
   水利机械设备行业网站 - 全局样式表
   版本: 2.0
   特点: 语义化、SEO友好、响应式设计
   ======================================== */

/* CSS变量定义 */
:root {
    --primary-color: #1a5fb4;
    --primary-dark: #154a8c;
    --primary-light: #3584e4;
    --secondary-color: #26a269;
    --accent-color: #e01b24;
    --text-dark: #1c1c1c;
    --text-medium: #4a4a4a;
    --text-light: #6e6e6e;
    --bg-light: #f6f8fa;
    --bg-white: #ffffff;
    --border-color: #e1e4e8;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --container-width: 1200px;
}

/* 重置样式 */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

ul, ol {
    list-style: none;
}

/* 容器 */
.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* ========================================
   头部样式
   ======================================== */
.site-header {
    background: var(--bg-white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-top {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: #fff;
    padding: 8px 0;
    font-size: 14px;
}

.header-top .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-top-left {
    display: flex;
    align-items: center;
    gap: 20px;
}

.header-top-right {
    display: flex;
    align-items: center;
    gap: 15px;
}

.header-phone {
    font-weight: 600;
    font-size: 15px;
}

.header-phone strong {
    font-size: 18px;
    margin-left: 5px;
}

.header-main {
    padding: 15px 0;
}

.header-main .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Logo */
.site-logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-text h1 {
    font-size: 22px;
    font-weight: 700;
    color: var(--primary-color);
    line-height: 1.2;
}

.logo-text p {
    font-size: 13px;
    color: var(--text-light);
    margin-top: 2px;
}

/* 主导航 */
.main-navigation {
    display: flex;
    align-items: center;
}

.main-navigation ul {
    display: flex;
    gap: 5px;
}

.main-navigation a {
    display: block;
    padding: 12px 20px;
    color: var(--text-dark);
    font-weight: 500;
    font-size: 15px;
    border-radius: var(--radius-sm);
    position: relative;
}

.main-navigation a::after {
    content: '';
    position: absolute;
    bottom: 8px;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
    transform: translateX(-50%);
}

.main-navigation a:hover,
.main-navigation a.active {
    color: var(--primary-color);
    background: rgba(26, 95, 180, 0.05);
}

.main-navigation a:hover::after,
.main-navigation a.active::after {
    width: 60%;
}

/* 移动端菜单按钮 */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    padding: 10px;
    cursor: pointer;
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    margin: 5px 0;
    transition: var(--transition);
}

/* ========================================
   面包屑导航
   ======================================== */
.breadcrumb-nav {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    padding: 12px 0;
}

.breadcrumb-nav ol {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
    font-size: 14px;
}

.breadcrumb-nav li {
    display: flex;
    align-items: center;
    gap: 8px;
}

.breadcrumb-nav li:not(:last-child)::after {
    content: '/';
    color: var(--text-light);
}

.breadcrumb-nav a {
    color: var(--text-medium);
}

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

.breadcrumb-nav li:last-child {
    color: var(--text-light);
}

/* ========================================
   Banner区域
   ======================================== */
.hero-banner {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 50%, #0d3a6e 100%);
    color: #fff;
    padding: 80px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero-banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="50" cy="50" r="40" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="0.5"/></svg>');
    background-size: 100px 100px;
    opacity: 0.5;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-content h2 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 20px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.hero-content p {
    font-size: 18px;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* ========================================
   区块标题
   ======================================== */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 15px;
    position: relative;
    display: inline-block;
}

.section-header h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.section-header p {
    color: var(--text-light);
    font-size: 16px;
    margin-top: 25px;
}

/* ========================================
   产品分类
   ======================================== */
.category-section {
    padding: 80px 0;
    background: var(--bg-white);
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 25px;
}

.category-card {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 30px 20px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.category-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 28px;
}

.category-card h3 {
    font-size: 17px;
    font-weight: 600;
    color: var(--text-dark);
}

/* ========================================
   应用场景
   ======================================== */
.application-section {
    padding: 80px 0;
    background: var(--bg-light);
}

.application-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 30px;
}

.application-card {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 40px 30px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.application-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.application-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 25px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 32px;
}

.application-card h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 15px;
}

.application-card p {
    font-size: 15px;
    color: var(--text-medium);
    line-height: 1.6;
    margin: 0;
}

/* 响应式样式 */
@media (max-width: 768px) {
    .application-section {
        padding: 60px 0;
    }
    
    .application-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .application-card {
        padding: 30px 20px;
    }
    
    .application-icon {
        width: 60px;
        height: 60px;
        font-size: 24px;
        margin-bottom: 20px;
    }
    
    .application-card h3 {
        font-size: 16px;
        margin-bottom: 12px;
    }
    
    .application-card p {
        font-size: 14px;
        line-height: 1.5;
    }
}

/* ========================================
   产品列表
   ======================================== */
.products-section {
    padding: 80px 0;
}

.products-section:nth-child(even) {
    background: var(--bg-white);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 30px;
}

.product-card {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.product-image {
    position: relative;
    overflow: hidden;
    aspect-ratio: 4/3;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.product-card:hover .product-image img {
    transform: scale(1.05);
}

.product-info {
    padding: 20px;
}

.product-info h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-dark);
    line-height: 1.5;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

.product-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid var(--border-color);
    font-size: 13px;
    color: var(--text-light);
}

/* ========================================
   产品详情页
   ======================================== */
.product-detail-section {
    padding: 40px 0 80px;
}

.product-detail-main {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    margin-bottom: 60px;
}

.product-gallery {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.product-gallery img {
    width: 100%;
    height: 450px;
    object-fit: cover;
}

.product-details {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.product-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-dark);
    line-height: 1.3;
}

.product-params {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 25px;
    box-shadow: var(--shadow-sm);
}

.product-params dl {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 15px 20px;
}

.product-params dt {
    color: var(--text-light);
    font-weight: 500;
}

.product-params dd {
    color: var(--text-dark);
    font-weight: 600;
}

.product-contact-box {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: #fff;
    padding: 30px;
    border-radius: var(--radius-md);
    text-align: center;
}

.product-contact-box h4 {
    font-size: 18px;
    margin-bottom: 15px;
}

.product-contact-box .phone {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 15px;
    line-height: 1.2;
}

/* 产品介绍 */
.product-intro {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 25px;
    margin-top: 20px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.product-intro h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
}

.product-intro p {
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-medium);
    margin: 0;
}

/* 响应式样式 */
@media (max-width: 768px) {
    .product-intro {
        padding: 20px;
        margin-top: 15px;
    }
    
    .product-intro h3 {
        font-size: 16px;
        margin-bottom: 12px;
    }
    
    .product-intro p {
        font-size: 14px;
        line-height: 1.5;
    }
    
    .product-contact-box .phone {
        font-size: 24px;
    }
}

.product-description {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 40px;
    box-shadow: var(--shadow-sm);
}

.product-description h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border-color);
}

.product-description-content {
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-medium);
}

.product-description-content p {
    margin-bottom: 12px;
}

/* ========================================
   产品应用场景
   ======================================== */
.product-application {
    margin-top: 40px;
    padding: 30px;
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.product-application h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 25px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border-color);
}

.product-application .application-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.product-application .application-card {
    background: var(--bg-light);
    border-radius: var(--radius-md);
    padding: 30px 20px;
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.product-application .application-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.product-application .application-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 15px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 24px;
}

.product-application .application-card h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 10px;
}

.product-application .application-card p {
    font-size: 14px;
    color: var(--text-medium);
    line-height: 1.5;
    margin: 0;
}

/* 响应式样式 */
@media (max-width: 768px) {
    .product-application {
        padding: 20px;
        margin-top: 30px;
    }
    
    .product-application .application-grid {
        grid-template-columns: 1fr;
        gap: 15px;
    }
    
    .product-application .application-card {
        padding: 25px 15px;
    }
    
    .product-application .application-icon {
        width: 50px;
        height: 50px;
        font-size: 20px;
        margin-bottom: 12px;
    }
    
    .product-application .application-card h4 {
        font-size: 15px;
        margin-bottom: 8px;
    }
    
    .product-application .application-card p {
        font-size: 13px;
        line-height: 1.4;
    }
}

/* ========================================
   新闻列表
   ======================================== */
.news-section {
    padding: 80px 0;
    background: var(--bg-white);
}

.news-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.news-item {
    display: flex;
    gap: 25px;
    padding: 25px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.news-item:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.news-date {
    flex-shrink: 0;
    width: 80px;
    text-align: center;
    padding: 15px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: #fff;
    border-radius: var(--radius-sm);
}

.news-date .day {
    display: block;
    font-size: 28px;
    font-weight: 700;
    line-height: 1;
}

.news-date .month {
    display: block;
    font-size: 13px;
    margin-top: 5px;
}

.news-content {
    flex: 1;
}

.news-content h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 10px;
    line-height: 1.4;
}

.news-content p {
    color: var(--text-light);
    font-size: 14px;
    line-height: 1.6;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

/* ========================================
   新闻详情
   ======================================== */
.article-section {
    padding: 40px 0 80px;
}

.article-header {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 30px;
    border-bottom: 1px solid var(--border-color);
}

.article-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 20px;
    line-height: 1.4;
}

.article-meta {
    display: flex;
    justify-content: center;
    gap: 30px;
    color: var(--text-light);
    font-size: 14px;
}

.article-content {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 40px;
    box-shadow: var(--shadow-sm);
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-medium);
}

.article-content p {
    margin-bottom: 20px;
}

.article-content img {
    max-width: 100%;
    border-radius: var(--radius-md);
    margin: 20px 0;
}

/* ========================================
   分页
   ======================================== */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    margin-top: 50px;
    list-style: none;
}

.pagination ul,
.pagination li {
    list-style: none;
    margin: 0;
    padding: 0;
}

.pagination a,
.pagination span {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 15px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
}

.pagination a {
    background: var(--bg-white);
    color: var(--text-dark);
    border: 1px solid var(--border-color);
}

.pagination a:hover {
    background: var(--primary-color);
    color: #fff;
    border-color: var(--primary-color);
}

.pagination .current {
    background: var(--primary-color);
    color: #fff;
}

.pagination .disabled {
    color: var(--text-light);
    cursor: not-allowed;
}

/* ========================================
   页脚
   ======================================== */
.site-footer {
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    color: #fff;
    padding: 60px 0 0;
}

.footer-main {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 50px;
    margin-bottom: 40px;
}

.footer-brand h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 15px;
}

.footer-brand p {
    color: rgba(255,255,255,0.7);
    line-height: 1.8;
    margin-bottom: 20px;
}

.footer-contact p {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 10px;
    color: rgba(255,255,255,0.8);
}

.footer-links h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 20px;
    color: #fff;
}

.footer-links ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-links a {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
}

.footer-links a:hover {
    color: #fff;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding: 20px 0;
    text-align: center;
    color: rgba(255,255,255,0.6);
    font-size: 14px;
}

/* ========================================
   栏目介绍区域
   ======================================== */
.class-intro-section {
    background: var(--bg-light);
    padding: 40px 0;
    border-bottom: 1px solid var(--border-color);
}

.class-intro-content {
    background: var(--bg-white);
    padding: 40px 50px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.class-intro-content h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 20px;
    padding-bottom: 0;
    border-bottom: none;
    display: block;
}

.class-intro-content h2::after {
    display: none;
}

.class-intro-content p {
    color: var(--text-medium);
    line-height: 1.9;
    font-size: 16px;
    margin-bottom: 20px;
}

.class-intro-content p:last-child {
    margin-bottom: 0;
}

.class-intro-content strong {
    color: var(--primary-color);
    font-weight: 600;
}

.class-intro-content a {
    color: var(--primary-color);
    text-decoration: underline;
    transition: var(--transition);
}

.class-intro-content a:hover {
    color: var(--primary-dark);
}

/* ========================================
   响应式设计
   ======================================== */
@media (max-width: 1024px) {
    .product-detail-main {
        grid-template-columns: 1fr;
    }
    
    .product-gallery img {
        height: 350px;
    }
    
    .footer-main {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .header-main .container {
        flex-wrap: wrap;
    }
    
    .main-navigation {
        display: none;
        width: 100%;
        margin-top: 15px;
    }
    
    .main-navigation.active {
        display: block;
    }
    
    .main-navigation ul {
        flex-direction: column;
        gap: 0;
    }
    
    .main-navigation a {
        padding: 15px;
        border-bottom: 1px solid var(--border-color);
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .hero-banner {
        padding: 60px 0;
    }
    
    .hero-content h2 {
        font-size: 28px;
    }
    
    .class-intro-section {
        padding: 30px 0;
    }
    
    .class-intro-content {
        padding: 30px 25px;
    }
    
    .class-intro-content h2 {
        font-size: 16px;
    }
    
    .class-intro-content p {
        font-size: 15px;
    }
    
    .section-header h2 {
        font-size: 24px;
    }
    
    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 20px;
    }
    
    .news-item {
        flex-direction: column;
        gap: 15px;
    }
    
    .news-date {
        width: 100%;
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 10px;
        padding: 10px;
    }
    
    .footer-main {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .article-title {
        font-size: 22px;
    }
    
    .article-content {
        padding: 25px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .header-top .container {
        flex-direction: column;
        gap: 8px;
        text-align: center;
    }
    
    .logo-text h1 {
        font-size: 18px;
    }
    
    .hero-content h2 {
        font-size: 24px;
    }
    
    .products-grid {
        grid-template-columns: 1fr;
    }
    
    .category-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
    }
    
    .category-card {
        padding: 20px 15px;
    }
    
    .product-gallery img {
        height: 250px;
    }
    
    .product-title {
        font-size: 22px;
    }
    
    .product-params dl {
        grid-template-columns: 1fr;
        gap: 10px;
    }
    
    .pagination {
        flex-wrap: wrap;
    }
}

/* ========================================
   辅助类
   ======================================== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 10px; }
.mt-2 { margin-top: 20px; }
.mt-3 { margin-top: 30px; }
.mt-4 { margin-top: 40px; }

.mb-1 { margin-bottom: 10px; }
.mb-2 { margin-bottom: 20px; }
.mb-3 { margin-bottom: 30px; }
.mb-4 { margin-bottom: 40px; }

.hidden { display: none !important; }
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

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

.animate-fade-in {
    animation: fadeIn 0.6s ease-out forwards;
}