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

body {
    font-family: 'Noto Sans SC', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8f0 100%);
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部导航 */
header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 3px solid #4a6fa5;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 0;
}

.logo h1 {
    font-family: 'Source Serif Pro', serif;
    font-size: 1.8rem;
    color: #2c3e50;
    margin-bottom: 0.3rem;
}

.logo h1 i {
    color: #4a6fa5;
    margin-right: 10px;
}

.subtitle {
    font-size: 0.9rem;
    color: #7f8c8d;
    font-weight: 300;
}

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

.nav-links a {
    text-decoration: none;
    color: #34495e;
    font-weight: 500;
    font-size: 1rem;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-links a:hover {
    background: #f8f9fa;
    color: #4a6fa5;
}

.nav-links a.active {
    background: #4a6fa5;
    color: white;
}

.mobile-menu {
    display: none;
    font-size: 1.5rem;
    color: #2c3e50;
    cursor: pointer;
}

/* 英雄区域 */
.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
    padding: 4rem 0;
    margin-top: 2rem;
}

.hero-content h1 {
    font-family: 'Source Serif Pro', serif;
    font-size: 2.8rem;
    color: #2c3e50;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-content h1 i {
    color: #4a6fa5;
    margin-right: 15px;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: #4a6fa5;
    font-weight: 500;
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.1rem;
    color: #555;
    margin-bottom: 2rem;
    line-height: 1.8;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 0.9rem 1.8rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.btn-primary {
    background: #4a6fa5;
    color: white;
}

.btn-primary:hover {
    background: #3a5a8c;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(74, 111, 165, 0.3);
}

.btn-secondary {
    background: transparent;
    color: #4a6fa5;
    border-color: #4a6fa5;
}

.btn-secondary:hover {
    background: #4a6fa5;
    color: white;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: #4a6fa5;
    border: 2px solid #4a6fa5;
    padding: 0.7rem 1.5rem;
    font-size: 0.9rem;
}

.btn-outline:hover {
    background: #4a6fa5;
    color: white;
}

/* 拓扑图形 */
.topology-graphic {
    position: relative;
    width: 300px;
    height: 300px;
    margin: 0 auto;
}

.node {
    position: absolute;
    width: 60px;
    height: 60px;
    background: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: #4a6fa5;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border: 3px solid #4a6fa5;
    animation: float 6s ease-in-out infinite;
}

.node1 {
    top: 20%;
    left: 20%;
    animation-delay: 0s;
}

.node2 {
    top: 20%;
    right: 20%;
    animation-delay: 1s;
}

.node3 {
    bottom: 20%;
    left: 20%;
    animation-delay: 2s;
}

.node4 {
    bottom: 20%;
    right: 20%;
    animation-delay: 3s;
}

.connection {
    position: absolute;
    background: #4a6fa5;
    height: 3px;
    border-radius: 3px;
}

.conn1 {
    width: 120px;
    top: 50px;
    left: 80px;
    transform: rotate(45deg);
}

.conn2 {
    width: 120px;
    top: 50px;
    right: 80px;
    transform: rotate(-45deg);
}

.conn3 {
    width: 120px;
    bottom: 50px;
    left: 80px;
    transform: rotate(-45deg);
}

.conn4 {
    width: 120px;
    bottom: 50px;
    right: 80px;
    transform: rotate(45deg);
}

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

/* 特性卡片 */
.features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    padding: 3rem 0;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
}

.feature-icon {
    font-size: 2.5rem;
    color: #4a6fa5;
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.feature-card p {
    color: #666;
    font-size: 0.95rem;
}

/* 文档区域 */
.documents {
    padding: 3rem 0;
}

.documents h2 {
    font-family: 'Source Serif Pro', serif;
    font-size: 2.2rem;
    color: #2c3e50;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 15px;
}

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

.document-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    border-left: 5px solid #4a6fa5;
}

.document-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.document-header i {
    color: #4a6fa5;
}

.document-header h3 {
    font-size: 1.6rem;
    color: #2c3e50;
}

.document-card p {
    color: #666;
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.document-meta {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
    color: #7f8c8d;
    font-size: 0.9rem;
}

.document-meta i {
    margin-right: 5px;
}

/* 页脚 */
footer {
    background: #2c3e50;
    color: white;
    padding: 3rem 0 1.5rem;
    margin-top: 4rem;
}

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

.footer-logo h3 {
    font-family: 'Source Serif Pro', serif;
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-logo p {
    color: #bdc3c7;
    font-size: 0.9rem;
}

.footer-links h4,
.footer-info h4 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: #ecf0f1;
}

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

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

.footer-links a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #4a6fa5;
}

.footer-info p {
    color: #bdc3c7;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.footer-bottom {
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid #34495e;
    color: #95a5a6;
    font-size: 0.9rem;
}

/* 内容页面样式 */
.content-page {
    padding: 3rem 0;
}

.content-header {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    margin-bottom: 2rem;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.05);
}

.content-header h1 {
    font-family: 'Source Serif Pro', serif;
    font-size: 2.5rem;
    color: #2c3e50;
    margin-bottom: 1rem;
}

.content-header .subtitle {
    font-size: 1.1rem;
    color: #4a6fa5;
    font-style: italic;
    margin-bottom: 1.5rem;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #7f8c8d;
    font-size: 0.9rem;
    margin-bottom: 2rem;
}

.breadcrumb a {
    color: #4a6fa5;
    text-decoration: none;
}

.content-body {
    background: white;
    padding: 3rem;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.05);
    line-height: 1.8;
}

.content-body h1,
.content-body h2,
.content-body h3,
.content-body h4 {
    font-family: 'Source Serif Pro', serif;
    color: #2c3e50;
    margin: 2rem 0 1rem;
}

.content-body h1 { font-size: 2.2rem; }
.content-body h2 { font-size: 1.8rem; border-bottom: 2px solid #f0f0f0; padding-bottom: 0.5rem; }
.content-body h3 { font-size: 1.5rem; }
.content-body h4 { font-size: 1.2rem; }

.content-body p {
    margin-bottom: 1.5rem;
    color: #444;
    font-size: 1.05rem;
}

.content-body table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
    background: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    border-radius: 8px;
    overflow: hidden;
}

.content-body th,
.content-body td {
    padding: 1rem;
    border: 1px solid #e0e0e0;
    text-align: left;
}

.content-body th {
    background: #f8f9fa;
    font-weight: 600;
    color: #2c3e50;
}

.content-body tr:nth-child(even) {
    background: #fafafa;
}

.content-body blockquote {
    border-left: 4px solid #4a6fa5;
    padding-left: 1.5rem;
    margin: 2rem 0;
    font-style: italic;
    color: #555;
    background: #f9f9f9;
    padding: 1.5rem;
    border-radius: 0 8px 8px 0;
}

.content-body code {
    background: #f4f4f4;
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    color: #d63384;
}

.content-body pre {
    background: #2c3e50;
    color: #ecf0f1;
    padding: 1.5rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 2rem 0;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.5;
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: #4a6fa5;
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    box-shadow: 0 5px 15px rgba(74, 111, 165, 0.3);
    transition: all 0.3s ease;
    z-index: 1000;
    border: none;
    outline: none;
}

.back-to-top:hover {
    background: #3a5a8c;
    transform: translateY(-3px);
}

/* 响应式设计 */
@media (max-width: 992px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
    }

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

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

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

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .mobile-menu {
        display: block;
    }

    .hero-content h1 {
        font-size: 2.2rem;
    }

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

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

    .content-body {
        padding: 2rem 1rem;
    }

    .topology-graphic {
        width: 250px;
        height: 250px;
    }

    .node {
        width: 50px;
        height: 50px;
        font-size: 1.2rem;
    }
}