/* 全局基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: #333;
    background-color: #f5f5f5;
    line-height: 1.6;
}

a {
    color: #0066cc;
    text-decoration: none;
    transition: color 0.3s;
}

a:hover {
    color: #004499;
    text-decoration: underline;
}

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

/* 屏幕阅读器专用 */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* 头部 */
header {
    background-color: #fff;
    border-bottom: 1px solid #e0e0e0;
    padding: 12px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 20px;
    font-weight: bold;
    color: #333;
}

.logo a {
    color: #333;
    display: flex;
    align-items: center;
    gap: 8px;
}

/* 搜索框 */
.search-box {
    display: flex;
    gap: 4px;
}

.search-box input {
    padding: 8px 12px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
    min-width: 200px;
}

.search-box button {
    padding: 8px 16px;
    background-color: #0066cc;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}

.search-box button:hover {
    background-color: #004499;
}

/* 导航 */
nav {
    background-color: #fff;
    border-bottom: 1px solid #e0e0e0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

nav ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0;
}

nav li {
    flex: 0 0 auto;
}

nav a {
    display: block;
    padding: 12px 16px;
    color: #333;
    transition: background-color 0.3s, color 0.3s;
}

nav a:hover {
    background-color: #f0f0f0;
    color: #0066cc;
    text-decoration: none;
}

/* 主容器 */
main {
    max-width: 1200px;
    margin: 20px auto;
    padding: 0 15px;
}

/* 面包屑 */
.breadcrumb {
    font-size: 14px;
    margin: 15px 0;
    padding: 12px;
    background-color: #fafafa;
    border-radius: 4px;
    border-left: 3px solid #0066cc;
}

.breadcrumb ol {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0;
}

.breadcrumb li {
    display: inline-flex;
    align-items: center;
}

.breadcrumb a {
    padding: 0 4px;
    color: #0066cc;
    text-decoration: none;
    transition: color 0.3s;
}

.breadcrumb a:hover {
    color: #004499;
    text-decoration: underline;
}

.breadcrumb span {
    padding: 0 4px;
    color: #666;
}

.breadcrumb li:not(:last-child)::after {
    content: ">";
    padding: 0 6px;
    color: #999;
}

/* 页脚 */
footer {
    background-color: #333;
    color: #fff;
    margin-top: 40px;
    padding: 30px 0;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 20px;
}

.footer-section h3 {
    margin-bottom: 12px;
    font-size: 16px;
    font-weight: 600;
}

.footer-section p {
    font-size: 14px;
    line-height: 1.6;
    color: #ccc;
}

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

.footer-links li {
    margin-bottom: 8px;
}

.footer-links a {
    color: #ccc;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    border-top: 1px solid #555;
    padding-top: 20px;
    font-size: 13px;
    color: #aaa;
}

.footer-bottom a {
    color: #aaa;
    text-decoration: none;
}

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

/* SEO 内容区 */
.seo-content {
    max-width: 1200px;
    margin: 30px auto;
    padding: 20px 15px;
    background-color: #fafafa;
    border-radius: 4px;
}

.seo-content-wrapper h2 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #333;
}

.seo-content-wrapper p {
    font-size: 14px;
    line-height: 1.6;
    color: #666;
    margin-bottom: 15px;
}

.seo-keywords p {
    font-size: 14px;
    color: #666;
}

.seo-keywords a {
    margin-right: 12px;
    color: #0066cc;
    text-decoration: none;
}

.seo-keywords a:hover {
    text-decoration: underline;
    color: #004499;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        gap: 12px;
    }

    .search-box {
        width: 100%;
    }

    .search-box input {
        flex: 1;
        min-width: unset;
    }

    nav a {
        padding: 10px 12px;
        font-size: 14px;
    }

    .breadcrumb {
        font-size: 13px;
    }

    .breadcrumb a,
    .breadcrumb span {
        padding: 0 2px;
    }

    .breadcrumb li:not(:last-child)::after {
        padding: 0 4px;
    }

    .footer-container {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .footer-section {
        text-align: center;
    }
}