/* ===== 货运公司主题样式 (修正版) ===== */
/* 设计理念：可靠、专业、高效、全球化 */
/* 颜色主题：深蓝代表可靠，绿色代表环保高效，橙色代表活力 */

/* --- 1. 全局与基础样式 --- */
:root {
    --primary-color: #1a3c8b;      /* 深蓝 - 可靠专业 */
    --secondary-color: #2e7d32;    /* 深绿 - 环保高效 */
    --accent-color: #ff6d00;       /* 橙色 - 活力行动 */
    --dark-color: #1a237e;         /* 深蓝黑 */
    --light-color: #f5f9ff;        /* 浅蓝白 */
    --text-color: #2c3e50;         /* 深灰文本 */
    --border-color: #c5d1e6;       /* 浅蓝灰边框 */
    --white-color: #ffffff;
    --shadow: 0 6px 20px rgba(26, 60, 139, 0.12);
    /* 渐变定义 */
    --gradient-blue: linear-gradient(135deg, #1a3c8b 0%, #2c5aa0 100%);
    --gradient-green: linear-gradient(135deg, #2e7d32 0%, #4caf50 100%);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--white-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    overflow-x: hidden;
}

main {
    flex: 1;
}

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

h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--dark-color);
    margin-bottom: 1.2rem;
}

h2 {
    font-size: 2.8rem;
    text-align: center;
    margin-bottom: 3.5rem;
    position: relative;
    padding-bottom: 20px;
}

h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 5px;
    background: var(--gradient-green);
    border-radius: 3px;
}

h3 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

section {
    padding: 90px 0;
}

section:nth-of-type(odd) {
    background-color: var(--light-color);
}

/* [修正] 按钮样式重构 - 修复背景遮挡hover效果的问题 */
.btn {
    display: inline-block;
    padding: 14px 32px;
    /* 使用 background-size 技术实现滑动效果，确保文字可见 */
    background-image: linear-gradient(to right, 
        #1a3c8b 0%, 
        #2c5aa0 50%, 
        #2e7d32 50%, 
        #4caf50 100%);
    background-size: 200% 100%;
    background-position: 0 0;
    color: var(--white-color);
    text-decoration: none;
    border-radius: 6px;
    font-weight: 700;
    font-size: 1rem;
    letter-spacing: 0.5px;
    transition: all 0.4s ease;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(26, 60, 139, 0.2);
    text-align: center;
    z-index: 1;
}

.btn:hover {
    background-position: 100% 0; /* 背景向左滑动，显示绿色部分 */
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(26, 60, 139, 0.3);
    color: var(--white-color);
}

/* --- 2. 头部与导航 --- */
.main-header {
    background-color: var(--white-color);
    box-shadow: 0 4px 20px rgba(26, 60, 139, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
    transition: all 0.3s ease;
}

.main-header.scrolled {
    padding: 5px 0;
    background-color: rgba(255, 255, 255, 0.98);
    box-shadow: 0 5px 25px rgba(26, 60, 139, 0.15);
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
    transition: height 0.3s ease;
    position: relative; /* 为移动端菜单定位做准备 */
}

.main-header.scrolled .container {
    height: 70px;
}

.logo {
    font-size: 1.9rem;
    font-weight: 900;
    color: var(--primary-color);
    text-decoration: none;
    letter-spacing: 1px;
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.logo::before {
    content: '';
    display: inline-block;
    width: 36px;
    height: 36px;
    margin-right: 12px;
    background: var(--gradient-blue);
    border-radius: 50%;
    position: relative;
}

.logo::after {
    content: '→';
    display: inline-block;
    color: var(--accent-color);
    font-weight: 700;
    margin-left: 8px;
    transform: translateY(-2px);
}

.main-nav ul {
    display: flex;
    list-style: none;
}

.main-nav ul li {
    margin-left: 35px;
    position: relative;
}

.main-nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 600;
    font-size: 1.05rem;
    padding: 8px 0;
    position: relative;
    transition: color 0.3s ease;
}

.main-nav ul li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 3px;
    background: var(--gradient-green);
    border-radius: 2px;
    transition: width 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.main-nav ul li a:hover::after,
.main-nav ul li a.active::after {
    width: 100%;
}

.main-nav ul li a:hover {
    color: var(--primary-color);
}

.main-nav ul li a.active {
    color: var(--primary-color);
    font-weight: 700;
}

.menu-toggle {
    display: none;
    cursor: pointer;
    background: none;
    border: none;
    font-size: 1.8rem;
    color: var(--primary-color);
    padding: 5px;
}

/* --- 3. 英雄区域 --- */
#hero {
    background: var(--dark-color); /* 兜底色 */
    background: var(--gradient-blue);
    color: var(--white-color);
    min-height: 85vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 0 20px;
    position: relative;
    overflow: hidden;
}

#hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    /* 增加世界地图或网格纹理感 */
    background-image: 
        radial-gradient(circle at 20% 80%, rgba(255, 255, 255, 0.1) 2px, transparent 2px),
        radial-gradient(circle at 80% 20%, rgba(255, 255, 255, 0.1) 2px, transparent 2px);
    background-size: 60px 60px;
    opacity: 0.3;
}

.hero-content {
    max-width: 850px;
    position: relative;
    z-index: 2;
}

#hero h1 {
    font-size: 3.8rem;
    color: var(--white-color);
    margin-bottom: 1.5rem;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

#hero p {
    font-size: 1.35rem;
    max-width: 750px;
    margin: 0 auto 3rem;
    opacity: 0.95;
    line-height: 1.8;
}

/* Hero区域按钮特殊样式：默认绿色 */
#hero .btn {
    background-image: linear-gradient(to right, 
        #2e7d32 0%, 
        #4caf50 50%, 
        #1a3c8b 50%, 
        #2c5aa0 100%);
}
#hero .btn:hover {
    background-position: 100% 0; /* 滑动变蓝 */
}

/* --- 4. 解决方案 --- */
#solutions h2::after {
    background: var(--gradient-blue);
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 35px;
}

.solution-card {
    background-color: var(--white-color);
    padding: 35px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.4s ease;
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

.solution-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: var(--gradient-blue);
}

.solution-card:hover {
    transform: translateY(-12px);
    box-shadow: 0 15px 35px rgba(26, 60, 139, 0.2);
    border-color: var(--border-color);
}

.solution-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 25px;
    background: var(--light-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    box-shadow: 0 8px 20px rgba(26, 60, 139, 0.15);
}

/* PHP类名与CSS图标映射 
   (注意：PHP类名目前是科技类的，但CSS样式已对应为货运图标，等待PHP内容更新即可)
*/
.icon-cloud::before { content: '🚚'; font-size: 2.5rem; }    /* 对应 PHP: 云服务 -> CSS: 陆运 */
.icon-data::before { content: '🌐'; font-size: 2.5rem; }     /* 对应 PHP: 大数据 -> CSS: 全球网络 */
.icon-ai::before { content: '📦'; font-size: 2.5rem; }       /* 对应 PHP: AI -> CSS: 仓储 */
.icon-security::before { content: '🛡️'; font-size: 2.5rem; } /* 对应 PHP: 安全 -> CSS: 货物保险 */
.icon-iot::before { content: '🚢'; font-size: 2.5rem; }      /* 对应 PHP: IoT -> CSS: 海运 */
.icon-consult::before { content: '⚡'; font-size: 2.5rem; }  /* 对应 PHP: 咨询 -> CSS: 极速快递 */

.solution-card h3 {
    font-size: 1.6rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.solution-card p {
    color: #5a6c7d;
    font-size: 1rem;
    line-height: 1.7;
}

/* --- 5. 关于我们 --- */
#about .about-content {
    display: flex;
    align-items: center;
    gap: 60px;
}

.about-text {
    flex: 1;
}

.about-text p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.8;
    color: #4a5568;
}

.about-action {
    margin-top: 2.5rem;
}

.about-visual {
    flex: 1;
    height: 380px;
    background: var(--gradient-blue);
    border-radius: 15px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--white-color);
    font-size: 1.8rem;
    font-weight: 700;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.about-visual::before {
    content: '🚛 🚢 ✈️ 🚂';
    font-size: 4rem;
    letter-spacing: 20px;
    opacity: 0.7;
    animation: moveIcons 30s linear infinite;
}

@keyframes moveIcons {
    0% { transform: translateX(0); }
    100% { transform: translateX(-100px); }
}

.about-visual span {
    z-index: 1;
    margin-top: 20px;
    font-size: 1.3rem;
    letter-spacing: 2px;
}

/* --- 6. 最新动态/内容区域 --- */
.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 35px;
}

.news-card {
    background-color: var(--white-color);
    border-radius: 12px;
    box-shadow: var(--shadow);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: all 0.4s ease;
    border: 1px solid var(--border-color);
}

.news-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 35px rgba(26, 60, 139, 0.15);
}

/* 图片容器 */
.news-cover {
    height: 220px;
    width: 100%;
    overflow: hidden;
    position: relative;
    background: var(--gradient-blue);
}

.news-card:nth-child(2n) .news-cover {
    background: var(--gradient-green);
}

.news-card:nth-child(3n) .news-cover {
    background: linear-gradient(135deg, #ff6d00 0%, #ff9e40 100%);
}

/* 图片样式 */
.news-cover img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.7s ease;
}

.news-card:hover .news-cover img {
    transform: scale(1.1);
}

.news-content {
    padding: 25px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.news-content h4 {
    font-size: 1.35rem;
    margin-bottom: 0.8rem;
    line-height: 1.4;
}

.news-content h4 a {
    text-decoration: none;
    color: var(--dark-color);
    transition: color 0.3s;
}

.news-content h4 a:hover {
    color: var(--primary-color);
}

.news-meta {
    font-size: 0.9rem;
    color: #718096;
    margin-bottom: 1.2rem;
    display: flex;
    gap: 15px;
    align-items: center;
}

.news-meta a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
}

.news-meta a:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

.news-content p {
    flex-grow: 1;
    margin-bottom: 1.5rem;
    font-size: 1rem;
    color: #5a6c7d;
    line-height: 1.7;
}

.read-more-link {
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 700;
    align-self: flex-start;
    position: relative;
    padding-bottom: 5px;
    display: flex;
    align-items: center;
}

.read-more-link::after {
    content: '→';
    margin-left: 8px;
    transition: transform 0.3s ease;
}

.read-more-link:hover {
    color: var(--secondary-color);
}

.read-more-link:hover::after {
    transform: translateX(5px);
}

/* --- 分页样式 --- */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 15px;
    margin-top: 60px;
}

.page-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    color: var(--text-color);
    text-decoration: none;
    transition: all 0.3s;
    font-weight: 700;
    font-size: 1.1rem;
}

.page-btn:hover {
    background: var(--gradient-blue);
    color: #fff;
    border-color: var(--primary-color);
    transform: translateY(-3px);
}

.page-current {
    display: inline-flex;
    align-items: center;
    height: 40px;
    padding: 0 20px;
    font-weight: bold;
    color: var(--dark-color);
    background: var(--light-color);
    border-radius: 8px;
}

/* --- 7. FAQ --- */
.faq-accordion {
    max-width: 900px;
    margin: 0 auto;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.faq-item {
    border-bottom: 1px solid var(--border-color);
    background: var(--white-color);
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-question {
    width: 100%;
    background: var(--white-color);
    border: none;
    text-align: left;
    padding: 25px 30px;
    font-size: 1.2rem;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--dark-color);
    transition: all 0.3s ease;
}

.faq-question:hover {
    background-color: var(--light-color);
    color: var(--primary-color);
}

.faq-question::after {
    content: '+';
    font-size: 1.8rem;
    color: var(--primary-color);
    transition: transform 0.4s ease;
    font-weight: 300;
}

.faq-item.active .faq-question {
    background-color: var(--light-color);
    color: var(--primary-color);
}

.faq-item.active .faq-question::after {
    transform: rotate(45deg);
    color: var(--secondary-color);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease, padding 0.3s ease;
    padding: 0 30px;
}

.faq-item.active .faq-answer {
    padding: 0 30px 30px;
}

.faq-answer p {
    color: #5a6c7d;
    font-size: 1.05rem;
    line-height: 1.8;
    border-top: 1px dashed rgba(46, 125, 50, 0.3);
    padding: 20px 0;
    margin-top: 15px;
}

/* --- 8. Footer --- */
.main-footer {
    background: var(--dark-color);
    color: var(--light-color);
    padding: 70px 0 25px;
    margin-top: auto;
    position: relative;
}

.main-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 5px;
    background: var(--gradient-green);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 40px;
    margin-bottom: 50px;
}

.footer-column {
    flex: 1;
    min-width: 220px;
}

.footer-column h4 {
    color: var(--white-color);
    margin-bottom: 1.5rem;
    font-size: 1.3rem;
    position: relative;
    padding-bottom: 12px;
}

.footer-column h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 3px;
    background: var(--gradient-green);
    border-radius: 2px;
}

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

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

.footer-column ul li a {
    color: #cbd5e0;
    text-decoration: none;
    transition: all 0.3s ease;
    display: inline-block;
    padding: 3px 0;
}

.footer-column ul li a:hover {
    color: var(--white-color);
    transform: translateX(5px);
}

.footer-bottom {
    text-align: center;
    padding-top: 25px;
    border-top: 1px solid #374151;
    font-size: 0.95rem;
    color: #9ca3af;
}

.footer-bottom a {
    color: #cbd5e0;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-bottom a:hover {
    color: var(--white-color);
    text-decoration: underline;
}

/* --- CMS 页面样式 --- */
.breadcrumb {
    padding: 20px 0;
    font-size: 0.95rem;
    color: #718096;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 35px;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
}

.breadcrumb a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
}

.breadcrumb a:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

.breadcrumb span {
    margin: 0 12px;
    color: #cbd5e0;
}

.page-container {
    padding: 70px 0 110px;
}

.page-header {
    text-align: left;
    margin-bottom: 45px;
}

.page-header.center-header {
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    color: var(--dark-color);
}

.page-meta {
    color: #718096;
    font-size: 1rem;
    margin-top: 12px;
}

.page-meta a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
}

.page-meta a:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

/* [修正] 单页容器样式兜底 */
.single-post-wrapper {
    /* 配合PHP中的内联样式，这里做响应式兜底 */
    width: 100%;
    padding: 0 5px;
}

.markdown-body {
    color: var(--text-color);
    font-size: 1.1rem;
    line-height: 1.8;
    max-width: 100%;
    overflow-x: hidden;
}

.markdown-body h2 {
    font-size: 2rem;
    margin-top: 3rem;
    margin-bottom: 1.8rem;
    padding-bottom: 15px;
    border-bottom: 3px solid var(--light-color);
    text-align: left;
}

.markdown-body h2::after {
    display: none;
}

.markdown-body h3 {
    font-size: 1.6rem;
    margin-top: 2.5rem;
    margin-bottom: 1.2rem;
    color: var(--primary-color);
}

.markdown-body p {
    margin-bottom: 1.8rem;
}

.markdown-body ul,
.markdown-body ol {
    padding-left: 25px;
    margin-bottom: 1.8rem;
}

.markdown-body li {
    margin-bottom: 0.8rem;
}

.markdown-body img {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    margin: 25px auto; /* 修改为auto实现居中 */
    box-shadow: var(--shadow);
    display: block; /* 确保margin auto生效 */
}

.markdown-body blockquote {
    border-left: 5px solid var(--primary-color);
    background-color: #f0f7ff;
    padding: 25px;
    margin: 25px 0;
    border-radius: 0 10px 10px 0;
    font-style: italic;
    color: #4a5568;
    font-size: 1.1rem;
}

.markdown-body a {
    color: var(--primary-color);
    text-decoration: none;
    border-bottom: 1px dashed var(--primary-color);
    font-weight: 600;
}

.markdown-body a:hover {
    border-bottom-style: solid;
    color: var(--secondary-color);
}

.markdown-body hr {
    border: 0;
    height: 2px;
    background: linear-gradient(to right, transparent, var(--border-color), transparent);
    margin: 45px 0;
}

.markdown-body pre {
    background: #1a3c8b;
    color: #fff;
    padding: 25px;
    border-radius: 10px;
    overflow-x: auto;
    margin-bottom: 25px;
    font-size: 0.95rem;
}

/* [新增] 货运公司必备：表格样式 (运费表等) */
.markdown-body table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.markdown-body table th,
.markdown-body table td {
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    text-align: left;
}

.markdown-body table th {
    background-color: var(--light-color);
    color: var(--primary-color);
    font-weight: 700;
}

.markdown-body table tr:nth-child(even) {
    background-color: #fafbfc;
}

.post-tags {
    margin-top: 45px;
    padding-top: 25px;
    border-top: 2px solid var(--border-color);
}

.tag-pill {
    display: inline-block;
    background: var(--light-color);
    padding: 8px 18px;
    border-radius: 25px;
    color: var(--primary-color);
    text-decoration: none;
    font-size: 0.9rem;
    margin-right: 12px;
    margin-bottom: 12px;
    border: 2px solid var(--border-color);
    transition: all 0.3s;
    font-weight: 600;
}

.tag-pill:hover {
    background: var(--gradient-blue);
    color: #fff;
    border-color: var(--primary-color);
    transform: translateY(-3px);
}

.post-navigation {
    display: flex;
    justify-content: space-between;
    margin-top: 45px;
    padding-top: 25px;
    border-top: 2px solid var(--border-color);
}

.nav-next,
.nav-prev {
    max-width: 48%;
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 700;
    padding: 15px;
    border-radius: 10px;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.nav-next:hover,
.nav-prev:hover {
    color: var(--primary-color);
    border-color: var(--border-color);
    background-color: var(--light-color);
}

.nav-next span,
.nav-prev span {
    display: block;
    font-size: 0.85rem;
    color: #718096;
    font-weight: normal;
    margin-bottom: 8px;
}

.error-page {
    text-align: center;
    padding: 120px 0;
    min-height: 50vh; /* 调整高度防止footer挤压 */
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.error-page h1 {
    font-size: 6rem;
    color: var(--primary-color);
    margin-bottom: 0;
    text-shadow: 3px 3px 0 rgba(26, 60, 139, 0.1);
}

.error-page p {
    font-size: 1.6rem;
    margin-bottom: 40px;
    color: #5a6c7d;
}

.no-content {
    text-align: center;
    padding: 70px;
    color: #9ca3af;
    background: var(--light-color);
    border-radius: 12px;
    font-size: 1.2rem;
    grid-column: 1/-1;
}

/* --- 响应式设计 --- */
@media (max-width: 1100px) {
    h2 {
        font-size: 2.5rem;
    }
    
    #hero h1 {
        font-size: 3.2rem;
    }
    
    .solutions-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
}

@media (max-width: 900px) {
    #about .about-content {
        flex-direction: column;
        gap: 50px;
    }
    
    .about-visual {
        width: 100%;
        height: 300px;
    }
}

@media (max-width: 768px) {
    .logo {
        font-size: 1.7rem;
    }
    
    .menu-toggle {
        display: block;
    }
    
    /* [修正] 移动端菜单定位改为 absolute */
    .main-nav {
        position: absolute; /* 改为 absolute 紧贴 header 底部 */
        top: 100%; /* 完美衔接 header 底部，无视 header 高度变化 */
        left: 0;
        width: 100%;
        background-color: var(--white-color);
        flex-direction: column;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.5s ease-in-out;
        box-shadow: 0 10px 25px rgba(26, 60, 139, 0.15);
        z-index: 999;
    }
    
    .main-nav.active {
        max-height: 500px;
    }
    
    .main-nav ul {
        flex-direction: column;
        padding: 20px 0;
    }
    
    .main-nav ul li {
        margin: 0;
        text-align: center;
    }
    
    .main-nav ul li a {
        display: block;
        padding: 15px 20px;
        font-size: 1.1rem;
    }
    
    .main-nav ul li a::after {
        display: none;
    }
    
    #hero h1 {
        font-size: 2.7rem;
    }
    
    #hero p {
        font-size: 1.15rem;
    }
    
    h2 {
        font-size: 2.2rem;
    }
    
    section {
        padding: 70px 0;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 35px;
    }
    
    .footer-column h4::after {
        left: 50%;
        transform: translateX(-50%);
    }
    
    .post-navigation {
        flex-direction: column;
        gap: 25px;
    }
    
    .nav-next,
    .nav-prev {
        max-width: 100%;
    }
}

@media (max-width: 576px) {
    #hero h1 {
        font-size: 2.2rem;
    }
    
    #hero p {
        font-size: 1rem;
    }
    
    h2 {
        font-size: 1.9rem;
    }
    
    h3 {
        font-size: 1.5rem;
    }
    
    .btn {
        padding: 12px 25px;
        font-size: 0.95rem;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .solutions-grid {
        grid-template-columns: 1fr;
    }
    
    .error-page h1 {
        font-size: 4.5rem;
    }
    
    .error-page p {
        font-size: 1.3rem;
    }
    
    section {
        padding: 60px 0;
    }
    
    .page-header h1 {
        font-size: 2rem;
    }
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 10px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}