```css
/* ===== 设计变量 ===== */
:root {
    --bg-primary: #f8fafc;
    --bg-card: #ffffff;
    --bg-footer: #0f172a;
    --text-primary: #1F2937;
    --text-secondary: #334155;
    --text-heading: #0B1E33;
    --text-link: #1D4ED8;
    --text-btn: #ffffff;
    --btn-bg: #1A3A5F;
    --border-light: #cbd5e1;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --nav-bg: rgba(255,255,255,0.95);
    --hero-overlay: linear-gradient(135deg, #0b1e33cc 0%, #1a3a5fdd 100%);
    --code-bg: #eef2f6;
    --accent: #F1C40F;
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --glass-bg: rgba(255,255,255,0.1);
    --glass-border: rgba(255,255,255,0.2);
    --card-hover-shadow: 0 20px 40px rgba(0,0,0,0.15);
    --transition-default: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    --bg-primary: #0B1322;
    --bg-card: #1e293b;
    --bg-footer: #020617;
    --text-primary: #E2E8F0;
    --text-secondary: #CBD5E1;
    --text-heading: #F8FAFC;
    --text-link: #93C5FD;
    --text-btn: #0f172a;
    --btn-bg: #F1C40F;
    --border-light: #334155;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.7);
    --nav-bg: rgba(2, 6, 23, 0.9);
    --hero-overlay: linear-gradient(135deg, #020617dd, #1a3a5fbb);
    --code-bg: #1e293b;
    --glass-bg: rgba(0,0,0,0.2);
    --glass-border: rgba(255,255,255,0.1);
    --card-hover-shadow: 0 20px 40px rgba(0,0,0,0.5);
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    transition: background-color 0.3s ease, color 0.3s ease;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    color: var(--text-heading);
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 0.75rem;
    transition: color 0.3s;
}

p {
    color: var(--text-primary);
    margin-bottom: 1.2rem;
}

a {
    color: var(--text-link);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

a:hover {
    text-decoration: underline;
    color: var(--accent);
}

ul, ol {
    padding-left: 1.5rem;
    margin-bottom: 1rem;
}

img, svg {
    max-width: 100%;
    height: auto;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== 导航栏 ===== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--nav-bg);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid var(--border-light);
    box-shadow: 0 4px 30px rgba(0,0,0,0.1);
    transition: background 0.3s ease;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 70px;
    gap: 20px;
}

.logo a {
    font-size: 1.9rem;
    font-weight: 800;
    color: var(--text-heading);
    letter-spacing: -0.5px;
    transition: color 0.3s;
}

.logo span {
    color: #F1C40F;
    background: #1A3A5F;
    padding: 2px 10px;
    border-radius: 40px;
    font-size: 1.2rem;
    margin-left: 6px;
    display: inline-block;
    transform: rotate(-2deg);
    transition: transform 0.3s ease;
}

.logo span:hover {
    transform: rotate(2deg) scale(1.05);
}

.nav-links {
    display: flex;
    gap: 28px;
    align-items: center;
}

.nav-links a {
    color: var(--text-primary);
    font-weight: 500;
    font-size: 1.05rem;
    position: relative;
    padding: 5px 0;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s ease;
}

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

.theme-toggle, .mobile-menu {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-primary);
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 6px 10px;
    border-radius: 30px;
    transition: background 0.2s ease, transform 0.2s ease;
}

.theme-toggle:hover, .mobile-menu:hover {
    background: var(--code-bg);
    transform: scale(1.1);
}

.mobile-menu {
    display: none;
}

/* ===== 搜索框 ===== */
.search-bar {
    display: flex;
    border: 1px solid var(--border-light);
    border-radius: 40px;
    overflow: hidden;
    background: var(--bg-card);
    transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

.search-bar:focus-within {
    box-shadow: 0 0 0 3px rgba(241, 196, 15, 0.2);
    border-color: var(--accent);
}

.search-bar input {
    border: none;
    padding: 8px 16px;
    background: transparent;
    color: var(--text-primary);
    width: 180px;
    outline: none;
    font-size: 0.95rem;
}

.search-bar button {
    background: var(--btn-bg);
    color: var(--text-btn);
    border: none;
    padding: 6px 18px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.3s ease;
}

.search-bar button:hover {
    background: var(--accent);
    color: #0f172a;
}

.search-bar input::placeholder {
    color: var(--text-secondary);
    opacity: 0.8;
}

/* ===== 移动导航 ===== */
.mobile-nav {
    display: none;
    flex-direction: column;
    background: var(--bg-card);
    padding: 20px;
    gap: 16px;
    border-top: 1px solid var(--border-light);
    animation: slideDown 0.3s ease;
}

.mobile-nav.open {
    display: flex;
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

.mobile-nav a {
    color: var(--text-primary);
    padding: 10px;
    border-radius: 8px;
    transition: background 0.2s ease, padding-left 0.3s ease;
}

.mobile-nav a:hover {
    background: var(--code-bg);
    padding-left: 20px;
}

@media (max-width: 900px) {
    .nav-links, .search-bar {
        display: none;
    }
    .mobile-menu {
        display: block;
    }
    .header-inner {
        gap: 10px;
    }
}

/* ===== Hero 区域 ===== */
.hero {
    background: var(--hero-overlay), url('data:image/svg+xml,%3Csvg width="100%" height="100%" viewBox="0 0 800 400" xmlns="http://www.w3.org/2000/svg"%3E%3Cdefs%3E%3Cpattern id="a" width="60" height="60" patternUnits="userSpaceOnUse"%3E%3Cpath d="M20 20h40v40H20z" fill="none" stroke="%23f1c40f22" stroke-width="2"/%3E%3C/pattern%3E%3C/defs%3E%3Crect width="100%" height="100%" fill="url(%23a)"/%3E%3C/svg%3E');
    background-size: cover, auto;
    padding: 100px 0;
    color: white;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(241,196,15,0.15) 0%, transparent 70%);
    animation: rotate 20s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

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

.hero h1 {
    font-size: clamp(2.5rem, 6vw, 4rem);
    color: #ffffff;
    text-shadow: 0 4px 30px rgba(0,0,0,0.5);
    margin-bottom: 20px;
    animation: fadeInUp 0.8s ease;
}

.hero p {
    font-size: clamp(1.1rem, 2.5vw, 1.4rem);
    color: #f0f9ff;
    max-width: 800px;
    margin: 0 auto 30px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.6);
    font-weight: 400;
    animation: fadeInUp 0.8s ease 0.2s both;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.btn-group {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
    animation: fadeInUp 0.8s ease 0.4s both;
}

.btn {
    background: var(--accent);
    color: #0f172a;
    font-weight: 700;
    padding: 14px 32px;
    border-radius: 60px;
    font-size: 1.1rem;
    border: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: inline-flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 15px rgba(241, 196, 15, 0.3);
}

.btn:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 8px 25px rgba(241, 196, 15, 0.4);
    text-decoration: none;
}

.btn-outline {
    background: transparent;
    border: 2px solid white;
    color: white;
    box-shadow: none;
    backdrop-filter: blur(10px);
}

.btn-outline:hover {
    background: rgba(255,255,255,0.1);
    border-color: var(--accent);
    color: var(--accent);
    box-shadow: 0 8px 25px rgba(255,255,255,0.1);
}

/* ===== 通用区块 ===== */
.section-title {
    font-size: clamp(1.8rem, 4vw, 2.5rem);
    text-align: center;
    margin: 4rem 0 2.5rem;
    position: relative;
    font-weight: 800;
}

.section-title::after {
    content: "";
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), #e67e22);
    margin: 12px auto 0;
    border-radius: 4px;
    transition: width 0.5s ease;
}

.section-title:hover::after {
    width: 120px;
}

.grid-2, .grid-3 {
    display: grid;
    gap: 30px;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }

@media (max-width: 800px) {
    .grid-2, .grid-3 { grid-template-columns: 1fr; }
    .section-title { margin: 3rem 0 2rem; }
}

/* ===== 卡片 ===== */
.card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 30px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-light);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s ease, border-color 0.3s ease;
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--card-hover-shadow);
    border-color: var(--accent);
}

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

.card h3 {
    font-size: 1.4rem;
    margin-bottom: 12px;
    font-weight: 700;
}

.card h4 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    font-weight: 600;
}

.card p:last-child {
    margin-bottom: 0;
}

/* ===== 文章列表 ===== */
.article-list {
    list-style: none;
}

.article-list li {
    padding: 12px 0;
    border-bottom: 1px dashed var(--border-light);
    transition: padding-left 0.3s ease;
}

.article-list li:hover {
    padding-left: 10px;
}

.article-list a {
    font-weight: 600;
    font-size: 1.1rem;
    color: var(--text-heading);
}

.article-list a:hover {
    color: var(--accent);
    text-decoration: none;
}

.article-meta {
    color: var(--text-secondary);
    font-size: 0.9rem;
    display: block;
    margin-top: 5px;
}

/* ===== 表格 ===== */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    border-radius: 12px;
    overflow: hidden;
}

th, td {
    padding: 12px 16px;
    border: 1px solid var(--border-light);
    text-align: left;
    background: var(--bg-card);
    transition: background 0.2s ease;
}

th {
    background: var(--btn-bg);
    color: var(--text-btn);
    font-weight: 600;
}

tr:hover td {
    background: var(--code-bg);
}

/* ===== FAQ ===== */
.faq-item {
    background: var(--bg-card);
    border-radius: 14px;
    margin-bottom: 16px;
    padding: 6px 24px;
    border: 1px solid var(--border-light);
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.faq-item:hover {
    border-color: var(--accent);
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
}

.faq-question {
    cursor: pointer;
    font-weight: 700;
    font-size: 1.2rem;
    padding: 16px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-heading);
    transition: color 0.3s ease;
}

.faq-question:hover {
    color: var(--accent);
}

.faq-question span {
    font-size: 1.8rem;
    font-weight: 400;
    color: var(--accent);
    transition: transform 0.3s ease;
}

.faq-answer {
    padding-bottom: 20px;
    color: var(--text-primary);
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===== HowTo ===== */
.howto-step {
    display: flex;
    gap: 24px;
    margin: 24px 0;
    padding: 20px;
    border-radius: 16px;
    background: var(--code-bg);
    transition: transform 0.3s ease, background 0.3s ease;
}

.howto-step:hover {
    transform: translateX(10px);
    background: var(--bg-card);
}

.howto-num {
    background: linear-gradient(135deg, var(--btn-bg), var(--accent));
    color: white;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.4rem;
    flex-shrink: 0;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
}

/* ===== 页脚 ===== */
footer {
    background: var(--bg-footer);
    color: #cbd5e1;
    padding: 60px 0 20px;
    margin-top: 80px;
}

footer a {
    color: #93C5FD;
    transition: color 0.3s ease;
}

footer a:hover {
    color: var(--accent);
    text-decoration: none;
}

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

@media (max-width: 800px) {
    .footer-grid { grid-template-columns: 1fr; gap: 30px; }
    footer { padding: 40px 0 20px; }
}

.footer-bottom {
    border-top: 1px solid #1e293b;
    padding-top: 20px;
    font-size: 0.9rem;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
}

footer h4 {
    color: white !important;
    font-weight: 700;
    margin-bottom: 15px;
    position: relative;
    padding-bottom: 10px;
}

footer h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 30px;
    height: 2px;
    background: var(--accent);
}

/* ===== 返回顶部 ===== */
.back-to-top {
    position: fixed;
    bottom: 40px;
    right: 40px;
    background: linear-gradient(135deg, var(--btn-bg), var(--accent));
    color: white;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    border: none;
    box-shadow: 0 8px 24px rgba(0,0,0,0.3);
    z-index: 1000;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    opacity: 0.8;
}

.back-to-top:hover {
    transform: translateY(-5px) scale(1.1);
    opacity: 1;
    box-shadow: 0 12px 30px rgba(0,0,0,0.4);
}

@media (max-width: 768px) {
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }
}

/* ===== 滚动动画 ===== */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s cubic-bezier(0.4, 0, 0.2, 1), transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== 自定义滚动条 ===== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--btn-bg), var(--accent));
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, var(--accent), var(--btn-bg));
}

/* ===== 选中文本 ===== */
::selection {
    background: var(--accent);
    color: #0f172a;
}

/* ===== 焦点可访问性 ===== */
:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 2px;
}

/* ===== 响应式细节 ===== */
@media (max-width: 600px) {
    .container {
        padding: 0 16px;
    }
    
    .hero {
        padding: 60px 0;
    }
    
    .card {
        padding: 20px;
        border-radius: 16px;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 1rem;
    }
    
    .howto-step {
        flex-direction: column;
        gap: 15px;
    }
    
    .faq-item {
        padding: 6px 16px;
    }
    
    .logo a {
        font-size: 1.5rem;
    }
    
    .logo span {
        font-size: 0.9rem;
        padding: 2px 8px;
    }
}

/* ===== 打印样式 ===== */
@media print {
    .site-header, .back-to-top, .btn-group, .search-bar, .theme-toggle, .mobile-menu, .mobile-nav {
        display: none !important;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .card, .faq-item {
        box-shadow: none;
        border: 1px solid #ddd;
        break-inside: avoid;
    }
    
    .hero {
        background: none !important;
        color: black;
        padding: 20px 0;
    }
    
    .hero h1, .hero p {
        color: black;
        text-shadow: none;
    }
}

/* ===== 性能优化：动画只在需要时运行 ===== */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    .reveal {
        opacity: 1;
        transform: none;
    }
}
```