/* ========== 变量 & 全局 ========== */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #eff6ff;
    --bg: #f8f9fb;
    --bg-white: #ffffff;
    --text: #1a1a2e;
    --text-secondary: #5a5a7a;
    --text-muted: #8888a0;
    --border: #e8eaf0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,.06);
    --shadow: 0 4px 16px rgba(0,0,0,.08);
    --shadow-lg: 0 8px 32px rgba(0,0,0,.10);
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --max-width: 1200px;
    --green: #10b981;
    --orange: #f59e0b;
    --red: #ef4444;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    min-height: 100vh;
}

a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }

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

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ========== 导航栏 ========== */
.navbar {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
}
.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
}
.navbar-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text);
}
.navbar-brand .logo-icon {
    width: 36px; height: 36px;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 16px;
    font-weight: 800;
}
.navbar-brand .version {
    font-size: 12px;
    font-weight: 400;
    color: var(--text-muted);
    margin-left: 4px;
}
.nav-links { display: flex; align-items: center; gap: 32px; list-style: none; }
.nav-links a {
    font-size: 15px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color .2s;
}
.nav-links a:hover, .nav-links a.active { color: var(--primary); }
.nav-download-btn {
    background: var(--primary) !important;
    color: #fff !important;
    padding: 8px 20px;
    border-radius: 20px;
    font-size: 14px !important;
    transition: background .2s;
}
.nav-download-btn:hover { background: var(--primary-dark) !important; }

/* 移动端汉堡菜单 */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    width: 32px; height: 32px;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
}
.menu-toggle span {
    display: block;
    width: 22px; height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: .3s;
}

/* ========== Hero ========== */
.hero {
    background: linear-gradient(160deg, #eff6ff 0%, #dbeafe 40%, #f0f7ff 100%);
    padding: 80px 0 60px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.hero::before {
    content: '';
    position: absolute;
    width: 400px; height: 400px;
    background: radial-gradient(circle, rgba(37,99,235,.08) 0%, transparent 70%);
    top: -100px; right: -100px;
    border-radius: 50%;
}
.hero::after {
    content: '';
    position: absolute;
    width: 300px; height: 300px;
    background: radial-gradient(circle, rgba(37,99,235,.06) 0%, transparent 70%);
    bottom: -80px; left: -60px;
    border-radius: 50%;
}
.hero .container { position: relative; z-index: 1; }
.hero-badge {
    display: inline-block;
    background: var(--primary-light);
    color: var(--primary);
    font-size: 14px;
    font-weight: 600;
    padding: 6px 18px;
    border-radius: 20px;
    margin-bottom: 20px;
}
.hero h1 {
    font-size: 48px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 16px;
    background: linear-gradient(135deg, var(--text) 0%, var(--primary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 32px;
    line-height: 1.7;
}
.hero-actions {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 32px;
    border-radius: 28px;
    font-size: 16px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all .25s;
    text-decoration: none;
}
.btn-primary {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 4px 14px rgba(37,99,235,.35);
}
.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(37,99,235,.4);
    color: #fff;
}
.btn-outline {
    background: var(--bg-white);
    color: var(--primary);
    border: 2px solid var(--primary);
}
.btn-outline:hover {
    background: var(--primary-light);
    color: var(--primary-dark);
}
.btn-lg { padding: 16px 40px; font-size: 18px; border-radius: 30px; }
.btn-sm { padding: 8px 20px; font-size: 14px; border-radius: 20px; }

/* ========== 数据亮点条 ========== */
.stats-bar {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border);
    padding: 24px 0;
}
.stats-list {
    display: flex;
    justify-content: center;
    gap: 48px;
    list-style: none;
    flex-wrap: wrap;
}
.stat-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
    color: var(--text-secondary);
}
.stat-item .stat-icon {
    width: 40px; height: 40px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    flex-shrink: 0;
}
.stat-icon.blue { background: #eff6ff; color: var(--primary); }
.stat-icon.green { background: #ecfdf5; color: var(--green); }
.stat-icon.orange { background: #fffbeb; color: var(--orange); }
.stat-icon.purple { background: #f5f3ff; color: #8b5cf6; }

.stat-text strong {
    display: block;
    font-size: 16px;
    color: var(--text);
    font-weight: 700;
}
.stat-text span {
    font-size: 12px;
    color: var(--text-muted);
}

/* ========== 通用 section ========== */
.section {
    padding: 72px 0;
}
.section-header {
    text-align: center;
    margin-bottom: 48px;
}
.section-header h2 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 12px;
}
.section-header p {
    font-size: 16px;
    color: var(--text-secondary);
    max-width: 560px;
    margin: 0 auto;
}

/* ========== 特性卡片 ========== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.feature-card {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 32px 28px;
    border: 1px solid var(--border);
    transition: all .3s;
}
.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.feature-card .feature-icon {
    width: 48px; height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    margin: 0 auto 16px auto;
    background: var(--primary-light);
    color: var(--primary);
    flex-shrink: 0;
}
.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}
.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ========== 截图区域 ========== */
.screenshot-wrap {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: var(--shadow);
    text-align: center;
    border: 1px solid var(--border);
}
.screenshot-wrap img {
    border-radius: 8px;
    border: 1px solid var(--border);
    margin: 0 auto;
    display: block;
}
.screenshot-caption {
    margin-top: 12px;
    font-size: 13px;
    color: var(--text-muted);
}

/* ========== 竞品对比 ========== */
.compare-table {
    width: 100%;
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    border-collapse: separate;
    border-spacing: 0;
    overflow: hidden;
    box-shadow: var(--shadow);
}
.compare-table thead th {
    background: #f9fafb;
    padding: 16px 20px;
    text-align: left;
    font-size: 14px;
    font-weight: 700;
    color: var(--text);
    border-bottom: 2px solid var(--border);
}
.compare-table thead th:first-child { border-radius: var(--radius-lg) 0 0 0; }
.compare-table thead th:last-child { border-radius: 0 var(--radius-lg) 0 0; }
.compare-table tbody td {
    padding: 14px 20px;
    font-size: 14px;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border);
}
.compare-table tbody tr:last-child td { border-bottom: none; }
.compare-table tbody td:first-child {
    font-weight: 600;
    color: var(--text);
}
.check { color: var(--green); font-weight: 700; }
.cross { color: var(--text-muted); }
.highlight-col { background: #f8faff; }

/* ========== 使用步骤 ========== */
.steps-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    counter-reset: step;
}
.step-item {
    background: var(--bg-white);
    border-radius: var(--radius);
    padding: 28px 24px;
    border: 1px solid var(--border);
    text-align: center;
    position: relative;
}
.step-item::before {
    counter-increment: step;
    content: counter(step);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px; height: 40px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 12px;
}
.step-item h3 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 6px;
}
.step-item p {
    font-size: 14px;
    color: var(--text-secondary);
}

/* ========== 下载卡片 ========== */
.download-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    max-width: 800px;
    margin: 0 auto;
}
.download-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    border: 2px solid var(--border);
    text-align: center;
    transition: all .3s;
    cursor: pointer;
}
.download-card.featured {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(37,99,235,.08);
    position: relative;
}
.download-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 4px;
}
.download-card .dl-speed {
    font-size: 13px;
    color: var(--green);
    font-weight: 600;
    margin-bottom: 12px;
}
.download-card .dl-size {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 16px;
}
.download-card .dl-pwd {
    font-size: 13px;
    color: var(--orange);
    font-weight: 600;
    margin-bottom: 12px;
}
.download-card .btn { width: 100%; max-width: 220px; }

/* 设备检测提示 */
.device-tip {
    display: none;
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 8px;
}

/* ========== 二维码弹窗 ========== */
.qr-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,.55);
    z-index: 200;
    align-items: center;
    justify-content: center;
}
.qr-overlay.show { display: flex; }

.qr-modal-new {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    max-width: 580px;
    width: 92%;
    position: relative;
    overflow: hidden;
}
.qr-close-btn {
    position: absolute;
    top: 12px; right: 16px;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-muted);
    cursor: pointer;
    line-height: 1;
    z-index: 10;
    width: 32px; height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all .2s;
}
.qr-close-btn:hover { background: #f1f3f5; color: var(--text); }

.qr-modal-body {
    display: flex;
    padding: 36px 32px 24px;
    gap: 32px;
    align-items: center;
}
.qr-modal-left {
    flex: 0 0 auto;
    text-align: center;
}
.qr-modal-right {
    flex: 1;
}
.qr-modal-right h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text);
}
.qr-modal-tip {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 10px;
    text-align: center;
}

/* 资源特性列表 */
.qr-feature-list {
    list-style: none;
    padding: 0;
}
.qr-feature-list li {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.8;
    padding: 4px 0;
    padding-left: 20px;
    position: relative;
}
.qr-feature-list li::before {
    content: '';
    position: absolute;
    left: 0; top: 12px;
    width: 8px; height: 8px;
    border-radius: 50%;
    background: var(--primary);
    opacity: 0.5;
}

.qr-modal-footer {
    text-align: center;
    padding: 0 32px 28px;
}
.qr-direct-link {
    display: inline-block;
    font-size: 14px;
    color: var(--primary);
    text-decoration: underline;
    cursor: pointer;
    transition: color .2s;
}
.qr-direct-link:hover { color: var(--primary-dark); }

/* ========== QR 动画边框 ========== */
.qr-img-animated {
    border-radius: 10px;
    padding: 4px;
    background: linear-gradient(135deg, #6094f0, #2563eb, #7c3aed, #4f8df5, #6094f0);
    background-size: 300% 300%;
    animation: qrBorderPulse 4s ease-in-out infinite;
    box-shadow: 0 0 12px rgba(37,99,235,.15);
}
.qr-img-animated img,
img.qr-img-animated {
    display: block;
    border-radius: 7px;
}
img.qr-img-animated {
    border: none;
    padding: 4px;
}

@keyframes qrBorderPulse {
    0% { background-position: 0% 50%; box-shadow: 0 0 12px rgba(37,99,235,.15); }
    25% { background-position: 50% 0%; box-shadow: 0 0 16px rgba(124,58,237,.20); }
    50% { background-position: 100% 50%; box-shadow: 0 0 12px rgba(37,99,235,.15); }
    75% { background-position: 50% 100%; box-shadow: 0 0 16px rgba(79,141,245,.20); }
    100% { background-position: 0% 50%; box-shadow: 0 0 12px rgba(37,99,235,.15); }
}

/* ========== 卡片内联 QR ========== */
.card-qr-img {
    width: 130px;
    height: 130px;
    margin: 0 auto 16px;
}
.card-qr-wrap {
    display: flex;
    justify-content: center;
    margin-bottom: 12px;
}

/* ========== CTA ========== */
.cta-section {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    text-align: center;
    padding: 64px 0;
    border-radius: var(--radius-lg);
    margin: 0 24px;
}
.cta-section h2 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 8px;
}
.cta-section p {
    font-size: 16px;
    opacity: .9;
    margin-bottom: 24px;
}
.cta-section .btn {
    background: #fff;
    color: var(--primary);
    font-weight: 700;
}
.cta-section .btn:hover {
    background: #f0f4ff;
}
.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}
.cta-buttons .btn-outline {
    background: transparent;
    color: #fff;
    border-color: rgba(255,255,255,.7);
}
.cta-buttons .btn-outline:hover {
    background: rgba(255,255,255,.15);
    color: #fff;
}

/* ========== 页脚 ========== */
.footer {
    background: var(--bg-white);
    border-top: 1px solid var(--border);
    padding: 32px 0;
    text-align: center;
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 72px;
}
.footer a { color: var(--text-secondary); }
.footer a:hover { color: var(--primary); }

/* ========== 功能介绍页 ========== */
.feature-detail {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 40px 36px;
    border: 1px solid var(--border);
    margin-bottom: 24px;
}
.feature-detail h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.feature-detail h3 .fd-icon {
    width: 36px; height: 36px;
    border-radius: 8px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-light);
    color: var(--primary);
    font-size: 16px;
}
.feature-detail p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 8px;
}
.feature-detail ul {
    padding-left: 20px;
    margin-bottom: 8px;
}
.feature-detail ul li {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ========== 功能介绍页 v2 增强样式 ========== */

/* --- Hero --- */
.features-hero {
    background: linear-gradient(160deg, #eff6ff 0%, #e0e7ff 40%, #ede9fe 100%);
    padding: 72px 0 56px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.features-hero::before {
    content: '';
    position: absolute;
    width: 360px; height: 360px;
    background: radial-gradient(circle, rgba(37,99,235,.10) 0%, transparent 70%);
    top: -120px; right: -100px;
    border-radius: 50%;
}
.features-hero::after {
    content: '';
    position: absolute;
    width: 240px; height: 240px;
    background: radial-gradient(circle, rgba(139,92,246,.08) 0%, transparent 70%);
    bottom: -80px; left: -60px;
    border-radius: 50%;
}
.hero-pill {
    display: inline-block;
    background: rgba(37,99,235,.12);
    color: var(--primary);
    font-size: 13px;
    font-weight: 600;
    padding: 5px 18px;
    border-radius: 20px;
    margin-bottom: 16px;
    letter-spacing: .3px;
}
.features-hero-title {
    font-size: 40px;
    font-weight: 800;
    color: var(--text);
    margin-bottom: 12px;
    position: relative;
    z-index: 1;
}
.features-hero-sub {
    font-size: 17px;
    color: var(--text-secondary);
    max-width: 520px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

/* --- Section Badge --- */
.section-badge {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
    font-size: 13px;
    font-weight: 600;
    padding: 6px 18px;
    border-radius: 20px;
    margin-bottom: 16px;
    letter-spacing: .3px;
}

/* --- 分割线 --- */
.section-divider {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 16px 0;
    max-width: var(--max-width);
    margin: 0 auto;
}
.section-divider::before,
.section-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: linear-gradient(to right, transparent, var(--border), transparent);
    max-width: 420px;
}
.divider-dot {
    color: var(--primary);
    font-size: 10px;
    margin: 0 20px;
    opacity: 0.4;
}

/* --- 步骤展示 --- */
.steps-showcase {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    position: relative;
}
.step-card {
    text-align: center;
    position: relative;
    padding: 32px 20px 28px;
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    transition: all .3s;
    z-index: 1;
}
.step-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.step-num {
    position: absolute;
    top: -16px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--primary);
    color: #fff;
    font-size: 13px;
    font-weight: 700;
    padding: 3px 14px;
    border-radius: 12px;
    letter-spacing: .5px;
}
.step-icon-wrap {
    width: 56px; height: 56px;
    border-radius: 16px;
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px auto;
}
.step-emoji { font-size: 26px; }
.step-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}
.step-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.7;
}
.step-card kbd {
    display: inline-block;
    background: #f1f5f9;
    border: 1px solid #cbd5e1;
    border-radius: 4px;
    padding: 1px 7px;
    font-size: 13px;
    font-family: inherit;
    color: var(--text);
    box-shadow: 0 1px 0 #cbd5e1;
}

/* Step 箭头连接 */
.step-card:not(:last-child)::after {
    content: '→';
    position: absolute;
    right: -28px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 22px;
    color: var(--primary);
    opacity: 0.4;
    font-weight: 300;
    z-index: 0;
}

/* --- 功能卡片网格 --- */
.features-detail-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}
.fcv2 {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 32px 30px;
    border: 1px solid var(--border);
    transition: all .3s;
    position: relative;
    overflow: hidden;
}
.fcv2::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--primary-dark));
    opacity: 0;
    transition: opacity .3s;
}
.fcv2:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 40px rgba(0,0,0,.12);
    border-color: transparent;
}
.fcv2:hover::before { opacity: 1; }
.fcv2-icon {
    width: 52px; height: 52px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    margin-bottom: 16px;
    flex-shrink: 0;
    transition: transform .3s;
}
.fcv2:hover .fcv2-icon { transform: scale(1.1); }
.fcv2-body h3 {
    font-size: 19px;
    font-weight: 700;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 10px;
}
.fcv2-badge {
    display: inline-block;
    background: linear-gradient(135deg, #f59e0b, #f97316);
    color: #fff;
    font-size: 11px;
    font-weight: 700;
    padding: 2px 10px;
    border-radius: 10px;
    letter-spacing: .3px;
    vertical-align: middle;
}
.fcv2-body p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.75;
    margin-bottom: 10px;
}
.fcv2-body ul {
    padding-left: 18px;
    list-style: none;
}
.fcv2-body ul li {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.9;
    position: relative;
    padding-left: 16px;
}
.fcv2-body ul li::before {
    content: '';
    position: absolute;
    left: 0; top: 10px;
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--primary);
    opacity: 0.5;
}

/* ========== 关于页 ========== */
.about-section {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 36px;
    border: 1px solid var(--border);
    margin-bottom: 24px;
}
.about-section h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}
.about-section p, .about-section li {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.8;
}
.changelog-item {
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}
.changelog-item:last-child { border-bottom: none; }
.changelog-version {
    font-weight: 700;
    color: var(--primary);
    margin-right: 8px;
}
.changelog-date {
    color: var(--text-muted);
    font-size: 12px;
}

/* ========== 响应式 ========== */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: absolute;
        top: 60px; left: 0; right: 0;
        background: var(--bg-white);
        flex-direction: column;
        padding: 16px 24px;
        gap: 12px;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow);
    }
    .nav-links.show { display: flex; }
    .menu-toggle { display: flex; }

    .hero h1 { font-size: 32px; }
    .hero-subtitle { font-size: 15px; }
    .hero { padding: 48px 0 36px; }

    .stats-list { gap: 20px; }
    .stat-item { font-size: 13px; }

    .section { padding: 48px 0; }
    .section-header h2 { font-size: 26px; }

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

    .download-cards {
        grid-template-columns: 1fr;
    }

    .compare-table { font-size: 12px; }
    .compare-table thead th,
    .compare-table tbody td { padding: 10px 12px; }

    .cta-section { margin: 0 16px; padding: 48px 0; border-radius: var(--radius); }

    .qr-modal-new { max-width: 360px; }
    .qr-modal-body { flex-direction: column; gap: 20px; padding: 28px 24px 20px; }
    .qr-modal-left { flex: none; }
    .qr-modal-footer { padding: 0 24px 24px; }

    .features-hero-title { font-size: 28px; }
    .features-hero { padding: 48px 0 36px; }
    .features-hero::before { width: 200px; height: 200px; top: -80px; right: -60px; }
    .features-hero::after { width: 140px; height: 140px; bottom: -50px; left: -40px; }
    .steps-showcase { grid-template-columns: 1fr; gap: 36px; }
    .step-card:not(:last-child)::after {
        content: '↓';
        right: auto; top: auto;
        bottom: -28px; left: 50%;
        transform: translateX(-50%);
    }
    .features-detail-grid { grid-template-columns: 1fr; }
    .section-divider { padding: 8px 0; }
}

@media (max-width: 1024px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 480px) {
    .container { padding: 0 16px; }
    .hero h1 { font-size: 26px; }
    .steps-list { grid-template-columns: 1fr; }
    .feature-detail { padding: 24px 20px; }
    .about-section { padding: 24px 20px; }
}