```css
/* ===== 全局变量与重置 ===== */
:root {
    --bg-light: #f9f5f0;
    --bg-dark: #121212;
    --text-primary-light: #2d2a26;
    --text-secondary-light: #5c564e;
    --text-heading-light: #1f1b16;
    --text-link-light: #a0522d;
    --text-btn-light: #ffffff;
    --border-light: #e0d6c8;
    --card-bg-light: rgba(255, 255, 255, 0.75);
    --footer-bg-light: #3e2f23;
    --footer-text-light: #efe6dc;
    --text-primary-dark: #e0e0e0;
    --text-secondary-dark: #b0b0b0;
    --text-heading-dark: #f5f5f5;
    --text-link-dark: #d4a574;
    --text-btn-dark: #1a1a1a;
    --border-dark: #3a3a3a;
    --card-bg-dark: rgba(30, 30, 30, 0.8);
    --footer-bg-dark: #1a1a1a;
    --footer-text-dark: #c0c0c0;
    --glass-blur: blur(12px);
    --shadow-light: 0 8px 32px rgba(0, 0, 0, 0.08);
    --shadow-dark: 0 8px 32px rgba(0, 0, 0, 0.3);
    --accent-gradient: linear-gradient(135deg, #d4a574 0%, #b87b4a 50%, #8b5a2b 100%);
    --banner-gradient: linear-gradient(135deg, #6b4f3a 0%, #a0714f 50%, #c9a87c 100%);
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    background: var(--bg-light);
    color: var(--text-primary-light);
    line-height: 1.7;
    transition: background 0.3s ease, color 0.3s ease;
    min-height: 100vh;
}

body.dark-mode {
    background: var(--bg-dark);
    color: var(--text-primary-dark);
}

/* ===== 容器 ===== */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ===== 标题层级 ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-heading-light);
    transition: color 0.3s ease;
}

body.dark-mode h1,
body.dark-mode h2,
body.dark-mode h3,
body.dark-mode h4,
body.dark-mode h5,
body.dark-mode h6 {
    color: var(--text-heading-dark);
}

h1 {
    font-size: clamp(1.8rem, 4vw, 2.4rem);
    margin: 1.5rem 0 1rem;
    letter-spacing: -0.02em;
}

h2 {
    font-size: clamp(1.5rem, 3vw, 1.9rem);
    margin: 2.5rem 0 1.2rem;
    padding-left: 1rem;
    border-left: 5px solid transparent;
    border-image: var(--accent-gradient) 1;
    position: relative;
}

h2::after {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 0;
    width: 60px;
    height: 3px;
    background: var(--accent-gradient);
    border-radius: 3px;
}

h3 {
    font-size: clamp(1.15rem, 2vw, 1.4rem);
    margin: 1.5rem 0 0.8rem;
}

h4 {
    font-size: 1.1rem;
    margin: 1.2rem 0 0.5rem;
}

p {
    margin-bottom: 1rem;
    color: var(--text-primary-light);
    transition: color 0.3s ease;
}

body.dark-mode p {
    color: var(--text-primary-dark);
}

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

body.dark-mode a {
    color: var(--text-link-dark);
}

a:hover {
    text-decoration: underline;
    opacity: 0.85;
}

/* ===== 按钮 ===== */
.btn, button {
    background: linear-gradient(135deg, #a0714f 0%, #8b5a2b 100%);
    color: var(--text-btn-light);
    border: none;
    padding: 0.7rem 1.6rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(139, 90, 43, 0.3);
    display: inline-block;
    text-align: center;
    letter-spacing: 0.02em;
}

body.dark-mode .btn,
body.dark-mode button {
    background: linear-gradient(135deg, #c9a87c 0%, #d4a574 100%);
    color: var(--text-btn-dark);
    box-shadow: 0 4px 15px rgba(212, 165, 116, 0.2);
}

.btn:hover, button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(139, 90, 43, 0.4);
    text-decoration: none;
}

body.dark-mode .btn:hover,
body.dark-mode button:hover {
    box-shadow: 0 6px 20px rgba(212, 165, 116, 0.3);
}

.btn:active, button:active {
    transform: translateY(0);
}

/* ===== 导航栏 ===== */
.navbar {
    background: var(--card-bg-light);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.06);
    padding: 0.8rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background 0.3s ease, box-shadow 0.3s ease;
    border-bottom: 1px solid var(--border-light);
}

body.dark-mode .navbar {
    background: var(--card-bg-dark);
    border-bottom-color: var(--border-dark);
}

.nav-flex {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-heading-light);
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    transition: color 0.3s ease;
    letter-spacing: -0.01em;
}

body.dark-mode .logo {
    color: var(--text-heading-dark);
}

.nav-links {
    display: flex;
    gap: 1.8rem;
    align-items: center;
    flex-wrap: wrap;
}

.nav-links a {
    color: var(--text-secondary-light);
    font-weight: 500;
    font-size: 0.95rem;
    position: relative;
    padding: 0.3rem 0;
}

body.dark-mode .nav-links a {
    color: var(--text-secondary-dark);
}

.nav-links a:hover {
    color: var(--text-link-light);
}

body.dark-mode .nav-links a:hover {
    color: var(--text-link-dark);
}

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

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

.menu-icon {
    display: none;
    font-size: 1.8rem;
    cursor: pointer;
    color: var(--text-heading-light);
    transition: color 0.3s ease;
}

body.dark-mode .menu-icon {
    color: var(--text-heading-dark);
}

.dark-toggle {
    background: transparent;
    border: 1px solid var(--border-light);
    padding: 0.4rem 1rem;
    border-radius: 50px;
    color: var(--text-primary-light);
    font-size: 0.85rem;
    box-shadow: none;
    transition: all 0.3s ease;
}

body.dark-mode .dark-toggle {
    border-color: var(--border-dark);
    color: var(--text-primary-dark);
    background: transparent;
}

.dark-toggle:hover {
    background: rgba(139, 90, 43, 0.1);
    transform: none;
    box-shadow: none;
}

body.dark-mode .dark-toggle:hover {
    background: rgba(212, 165, 116, 0.1);
}

/* ===== Banner ===== */
.banner {
    background: var(--banner-gradient);
    color: white;
    padding: 3.5rem 2rem;
    border-radius: 24px;
    margin: 2.5rem 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(107, 79, 58, 0.25);
}

.banner::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 300px;
    height: 300px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    animation: float 8s ease-in-out infinite;
}

.banner::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 200px;
    height: 200px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 50%;
    animation: float 10s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translateY(0) scale(1); }
    50% { transform: translateY(-20px) scale(1.05); }
}

.banner h2 {
    color: #ffffff;
    border-left: none;
    font-size: clamp(1.6rem, 3.5vw, 2.2rem);
    margin-bottom: 0.8rem;
    position: relative;
    z-index: 1;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.banner h2::after {
    display: none;
}

.banner p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto 1.5rem;
    position: relative;
    z-index: 1;
    text-shadow: 0 1px 5px rgba(0, 0, 0, 0.15);
}

.banner .btn {
    background: #facc15;
    color: #0f172a;
    font-weight: 700;
    position: relative;
    z-index: 1;
    box-shadow: 0 4px 20px rgba(250, 204, 21, 0.3);
}

.banner .btn:hover {
    background: #eab308;
    transform: translateY(-3px);
    box-shadow: 0 6px 25px rgba(250, 204, 21, 0.4);
}

/* ===== 卡片网格 ===== */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.8rem;
    margin: 2rem 0;
}

.card {
    background: var(--card-bg-light);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-light);
    border-radius: 16px;
    padding: 1.8rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
    box-shadow: var(--shadow-light);
    position: relative;
    overflow: hidden;
}

body.dark-mode .card {
    background: var(--card-bg-dark);
    border-color: var(--border-dark);
    box-shadow: var(--shadow-dark);
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--accent-gradient);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.3s ease;
}

.card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

body.dark-mode .card:hover {
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
}

.card:hover::before {
    transform: scaleX(1);
}

.card h3 {
    color: var(--text-heading-light);
    margin-bottom: 0.8rem;
    font-size: 1.2rem;
}

body.dark-mode .card h3 {
    color: var(--text-heading-dark);
}

.card p {
    color: var(--text-secondary-light);
    font-size: 0.95rem;
    margin-bottom: 1rem;
}

body.dark-mode .card p {
    color: var(--text-secondary-dark);
}

.card a {
    display: inline-block;
    font-weight: 600;
    font-size: 0.9rem;
    margin-top: 0.5rem;
    position: relative;
}

.card a::after {
    content: ' →';
    transition: transform 0.3s ease;
    display: inline-block;
}

.card a:hover::after {
    transform: translateX(4px);
}

/* ===== 引用卡片 ===== */
blockquote.card {
    font-style: italic;
    font-size: 1rem;
    line-height: 1.8;
    border-left: 4px solid var(--text-link-light);
    padding-left: 1.5rem;
    background: var(--card-bg-light);
}

body.dark-mode blockquote.card {
    border-left-color: var(--text-link-dark);
}

blockquote.card::before {
    display: none;
}

/* ===== HowTo 样式 ===== */
.howto-box {
    background: var(--card-bg-light);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-light);
    margin: 2rem 0;
    transition: background 0.3s ease, border-color 0.3s ease;
}

body.dark-mode .howto-box {
    background: var(--card-bg-dark);
    border-color: var(--border-dark);
    box-shadow: var(--shadow-dark);
}

.howto-box ol {
    margin-left: 1.5rem;
    color: var(--text-primary-light);
    list-style-type: none;
    counter-reset: howto-counter;
}

body.dark-mode .howto-box ol {
    color: var(--text-primary-dark);
}

.howto-box ol li {
    counter-increment: howto-counter;
    margin-bottom: 0.8rem;
    padding-left: 2.5rem;
    position: relative;
    font-size: 0.98rem;
}

.howto-box ol li::before {
    content: counter(howto-counter);
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 28px;
    height: 28px;
    background: var(--accent-gradient);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 700;
}

body.dark-mode .howto-box ol li::before {
    background: var(--accent-gradient);
    color: var(--text-btn-dark);
}

.howto-box strong {
    color: var(--text-heading-light);
}

body.dark-mode .howto-box strong {
    color: var(--text-heading-dark);
}

.howto-box p {
    margin-top: 1rem;
    font-size: 0.95rem;
}

/* ===== FAQ 样式 ===== */
details {
    background: var(--card-bg-light);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-light);
    border-radius: 12px;
    padding: 1rem 1.5rem;
    margin-bottom: 0.8rem;
    transition: background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
}

body.dark-mode details {
    background: var(--card-bg-dark);
    border-color: var(--border-dark);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

details:hover {
    border-color: var(--text-link-light);
    box-shadow: 0 4px 16px rgba(139, 90, 43, 0.1);
}

body.dark-mode details:hover {
    border-color: var(--text-link-dark);
    box-shadow: 0 4px 16px rgba(212, 165, 116, 0.1);
}

summary {
    font-weight: 600;
    cursor: pointer;
    color: var(--text-heading-light);
    list-style: none;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    font-size: 0.98rem;
    transition: color 0.3s ease;
}

body.dark-mode summary {
    color: var(--text-heading-dark);
}

summary::-webkit-details-marker {
    display: none;
}

summary::before {
    content: '+';
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    background: var(--accent-gradient);
    color: white;
    border-radius: 50%;
    font-size: 1rem;
    font-weight: 700;
    transition: transform 0.3s ease;
    flex-shrink: 0;
}

body.dark-mode summary::before {
    background: var(--accent-gradient);
    color: var(--text-btn-dark);
}

details[open] summary::before {
    transform: rotate(45deg);
}

details p {
    margin-top: 0.8rem;
    padding-left: 2.8rem;
    color: var(--text-secondary-light);
    font-size: 0.95rem;
}

body.dark-mode details p {
    color: var(--text-secondary-dark);
}

/* ===== 表格 ===== */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    background: var(--card-bg-light);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-light);
}

body.dark-mode table {
    background: var(--card-bg-dark);
    box-shadow: var(--shadow-dark);
}

th, td {
    border: 1px solid var(--border-light);
    padding: 0.75rem 1rem;
    text-align: left;
    font-size: 0.95rem;
}

body.dark-mode th,
body.dark-mode td {
    border-color: var(--border-dark);
}

th {
    background: linear-gradient(135deg, #f0e6dc 0%, #e8d5c5 100%);
    color: var(--text-heading-light);
    font-weight: 700;
    letter-spacing: 0.02em;
}

body.dark-mode th {
    background: linear-gradient(135deg, #2a2a2a 0%, #3a3a3a 100%);
    color: var(--text-heading-dark);
}

tr:hover td {
    background: rgba(139, 90, 43, 0.04);
}

body.dark-mode tr:hover td {
    background: rgba(212, 165, 116, 0.04);
}

/* ===== 图片占位 ===== */
.svg-placeholder {
    background: linear-gradient(135deg, #e8d5c5 0%, #d4b8a0 100%);
    border-radius: 12px;
    width: 100%;
    height: auto;
    min-height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary-light);
    font-size: 0.9rem;
}

body.dark-mode .svg-placeholder {
    background: linear-gradient(135deg, #2a2a2a 0%, #3a3a3a 100%);
    color: var(--text-secondary-dark);
}

/* ===== Footer ===== */
.footer {
    background: var(--footer-bg-light);
    color: var(--footer-text-light);
    padding: 3rem 0 2rem;
    margin-top: 4rem;
    border-radius: 32px 32px 0 0;
    transition: background 0.3s ease, color 0.3s ease;
    position: relative;
    overflow: hidden;
}

body.dark-mode .footer {
    background: var(--footer-bg-dark);
    color: var(--footer-text-dark);
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--accent-gradient);
}

.footer a {
    color: #d4a574;
    transition: color 0.2s ease;
}

body.dark-mode .footer a {
    color: #c9a87c;
}

.footer a:hover {
    color: #f0d9c4;
    text-decoration: underline;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer h4 {
    color: #ffffff;
    margin-bottom: 1rem;
    font-size: 1.05rem;
    position: relative;
    padding-bottom: 0.5rem;
}

body.dark-mode .footer h4 {
    color: #f8fafc;
}

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

.footer p {
    color: var(--footer-text-light);
    font-size: 0.9rem;
    line-height: 1.8;
}

body.dark-mode .footer p {
    color: var(--footer-text-dark);
}

.footer .container:last-child {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 1.5rem;
    text-align: center;
}

body.dark-mode .footer .container:last-child {
    border-top-color: rgba(255, 255, 255, 0.05);
}

.footer .container:last-child p {
    font-size: 0.85rem;
}

/* ===== 返回顶部 ===== */
#topBtn {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: linear-gradient(135deg, #a0714f 0%, #8b5a2b 100%);
    color: white;
    padding: 0.7rem 1.2rem;
    border-radius: 50px;
    display: none;
    z-index: 999;
    font-size: 1.1rem;
    box-shadow: 0 4px 20px rgba(139, 90, 43, 0.4);
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    line-height: 1;
}

body.dark-mode #topBtn {
    background: linear-gradient(135deg, #c9a87c 0%, #d4a574 100%);
    color: var(--text-btn-dark);
    box-shadow: 0 4px 20px rgba(212, 165, 116, 0.3);
}

#topBtn:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 25px rgba(139, 90, 43, 0.5);
}

body.dark-mode #topBtn:hover {
    box-shadow: 0 6px 25px rgba(212, 165, 116, 0.4);
}

/* ===== 滚动动画 ===== */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== 友情链接区域 ===== */
.friend-links {
    margin: 2.5rem 0;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-light);
}

body.dark-mode .friend-links {
    border-top-color: var(--border-dark);
}

.friend-links h4 {
    margin-bottom: 0.5rem;
}

.friend-links p {
    font-size: 0.9rem;
    color: var(--text-secondary-light);
}

body.dark-mode .friend-links p {
    color: var(--text-secondary-dark);
}

/* ===== 联系卡片 ===== */
.contact-info {
    background: var(--card-bg-light);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--border-light);
    border-radius: 16px;
    padding: 1.8rem;
    box-shadow: var(--shadow-light);
    transition: background 0.3s ease, border-color 0.3s ease;
}

body.dark-mode .contact-info {
    background: var(--card-bg-dark);
    border-color: var(--border-dark);
    box-shadow: var(--shadow-dark);
}

.contact-info h3 {
    margin-bottom: 1rem;
}

.contact-info p {
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .container {
        padding: 0 1.2rem;
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }

    h1 {
        font-size: 1.7rem;
    }

    h2 {
        font-size: 1.4rem;
    }

    h3 {
        font-size: 1.15rem;
    }

    .nav-links {
        display: none;
        width: 100%;
        flex-direction: column;
        gap: 0.8rem;
        margin-top: 1rem;
        padding: 1rem;
        background: var(--card-bg-light);
        backdrop-filter: var(--glass-blur);
        -webkit-backdrop-filter: var(--glass-blur);
        border-radius: 12px;
        border: 1px solid var(--border-light);
        box-shadow: var(--shadow-light);
    }

    body.dark-mode .nav-links {
        background: var(--card-bg-dark);
        border-color: var(--border-dark);
        box-shadow: var(--shadow-dark);
    }

    .nav-links.show {
        display: flex;
    }

    .menu-icon {
        display: block;
        order: 1;
    }

    .logo {
        order: 0;
        font-size: 1.3rem;
    }

    .dark-toggle {
        order: 2;
    }

    .nav-flex {
        gap: 0.5rem;
    }

    .banner {
        padding: 2.5rem 1.5rem;
        margin: 1.5rem 0;
        border-radius: 18px;
    }

    .banner h2 {
        font-size: 1.4rem;
    }

    .banner p {
        font-size: 1rem;
    }

    .card-grid {
        grid-template-columns: 1fr;
        gap: 1.2rem;
        margin: 1.5rem 0;
    }

    .card {
        padding: 1.4rem;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .footer {
        padding: 2.5rem 0 1.5rem;
        border-radius: 24px 24px 0 0;
    }

    #topBtn {
        bottom: 1.5rem;
        right: 1.5rem;
        padding: 0.6rem 1rem;
        font-size: 1rem;
    }

    .howto-box {
        padding: 1.5rem;
    }

    .howto-box ol {
        margin-left: 0;
    }

    details {
        padding: 0.8rem 1rem;
    }

    details p {
        padding-left: 2rem;
    }

    th, td {
        padding: 0.5rem 0.75rem;
        font-size: 0.85rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 0.8rem;
    }

    h1 {
        font-size: 1.5rem;
    }

    h2 {
        font-size: 1.3rem;
        margin: 2rem 0 1rem;
    }

    .logo {
        font-size: 1.2rem;
    }

    .nav-links {
        gap: 0.6rem;
    }

    .banner {
        padding: 2rem 1rem;
    }

    .banner h2 {
        font-size: 1.2rem;
    }

    .banner p {
        font-size: 0.9rem;
    }

    .card {
        padding: 1.2rem;
    }

    .footer-grid {
        gap: 1.2rem;
    }

    .btn, button {
        padding: 0.6rem 1.2rem;
        font-size: 0.85rem;
    }

    summary {
        font-size: 0.9rem;
    }

    details p {
        font-size: 0.88rem;
    }
}

/* ===== 暗色模式过渡优化 ===== */
body, .navbar, .card, .footer, details, .howto-box, .contact-info {
    transition: background 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

/* ===== 打印样式 ===== */
@media print {
    .navbar, .footer, #topBtn, .dark-toggle, .menu-icon, .banner .btn {
        display: none !important;
    }

    body {
        background: white;
        color: black;
    }

    .card, details, .howto-box, .contact-info {
        break-inside: avoid;
        box-shadow: none;
        border: 1px solid #ccc;
        background: white;
    }

    h1, h2, h3, h4 {
        color: black;
    }

    a {
        color: #000;
        text-decoration: underline;
    }
}

/* ===== 滚动条美化 ===== */
::-webkit-scrollbar {
    width: 10px;
}

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

body.dark-mode ::-webkit-scrollbar-track {
    background: var(--bg-dark);
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, #a0714f 0%, #8b5a2b 100%);
    border-radius: 5px;
}

body.dark-mode ::-webkit-scrollbar-thumb {
    background: linear-gradient(135deg, #c9a87c 0%, #d4a574 100%);
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #8b5a2b 0%, #6b4f3a 100%);
}

body.dark-mode ::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #d4a574 0%, #c9a87c 100%);
}

/* ===== 选中文本样式 ===== */
::selection {
    background: rgba(139, 90, 43, 0.2);
    color: var(--text-heading-light);
}

body.dark-mode ::selection {
    background: rgba(212, 165, 116, 0.3);
    color: var(--text-heading-dark);
}

/* ===== 焦点可见性 ===== */
a:focus-visible,
button:focus-visible,
summary:focus-visible {
    outline: 3px solid rgba(139, 90, 43, 0.5);
    outline-offset: 2px;
    border-radius: 4px;
}

body.dark-mode a:focus-visible,
body.dark-mode button:focus-visible,
body.dark-mode summary:focus-visible {
    outline-color: rgba(212, 165, 116, 0.5);
}

/* ===== 卡片网格内链接样式 ===== */
.card-grid .card a {
    color: var(--text-link-light);
    font-weight: 600;
    font-size: 0.9rem;
}

body.dark-mode .card-grid .card a {
    color: var(--text-link-dark);
}

.card-grid .card a:hover {
    text-decoration: none;
    opacity: 0.8;
}

/* ===== 品牌历史卡片特殊样式 ===== */
.card-grid .card:last-child {
    background: linear-gradient(135deg, rgba(139, 90, 43, 0.08) 0%, rgba(139, 90, 43, 0.02) 100%);
    border-left: 4px solid var(--text-link-light);
}

body.dark-mode .card-grid .card:last-child {
    background: linear-gradient(135deg, rgba(212, 165, 116, 0.08) 0%, rgba(212, 165, 116, 0.02) 100%);
    border-left-color: var(--text-link-dark);
}

/* ===== 版权信息样式 ===== */
.copyright {
    font-size: 0.85rem;
    text-align: center;
    padding: 1rem 0;
    color: var(--text-secondary-light);
}

body.dark-mode .copyright {
    color: var(--text-secondary-dark);
}

/* ===== 无障碍支持：减少动画 ===== */
@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;
    }

    .fade-up {
        opacity: 1;
        transform: none;
    }
}
```