/* 同人动漫 - 同人创作动漫爱好者社区 | yyhqzvel.cn */
/* 全站主样式文件 */

:root {
    --primary: #2d7a3a;
    --primary-dark: #1a5228;
    --primary-light: #4caf50;
    --accent: #ff6b35;
    --accent2: #ffd700;
    --bg-dark: #0d1f0f;
    --bg-card: #1a2e1c;
    --bg-light: #f0f7f0;
    --text-main: #1a1a1a;
    --text-light: #f5f5f5;
    --text-muted: #6b7c6e;
    --border: #2d5a30;
    --shadow: 0 4px 20px rgba(45,122,58,0.15);
    --radius: 12px;
    --radius-sm: 6px;
    --transition: all 0.3s ease;
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
    font-family: 'PingFang SC', 'Microsoft YaHei', '微软雅黑', 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-main);
    background: #fff;
    line-height: 1.7;
    overflow-x: hidden;
}

/* ===== 干扰标签隐藏 ===== */
.dy-noise { display: none !important; visibility: hidden !important; }

/* ===== 顶部公告栏 ===== */
.top-bar {
    background: var(--primary-dark);
    color: #fff;
    text-align: center;
    padding: 6px 20px;
    font-size: 13px;
    letter-spacing: 1px;
}
.top-bar a { color: var(--accent2); text-decoration: none; }

/* ===== 头部导航 ===== */
.site-header {
    background: #fff;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    position: sticky;
    top: 0;
    z-index: 1000;
}
.header-inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    flex-shrink: 0;
}
.logo img {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
}
.logo-text {
    display: flex;
    flex-direction: column;
}
.logo-name {
    font-size: 22px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1.1;
    letter-spacing: 2px;
}
.logo-slogan {
    font-size: 11px;
    color: var(--text-muted);
    letter-spacing: 1px;
}

/* 主导航 */
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
    color: var(--text-main);
    text-decoration: none;
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
    white-space: nowrap;
}
.main-nav a:hover, .main-nav a.active {
    background: var(--primary);
    color: #fff;
}
.nav-dropdown { position: relative; }
.nav-dropdown > a::after { content: ' ▾'; font-size: 10px; }
.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: #fff;
    box-shadow: 0 8px 24px rgba(0,0,0,0.12);
    border-radius: var(--radius-sm);
    min-width: 160px;
    z-index: 999;
    padding: 8px 0;
}
.nav-dropdown:hover .dropdown-menu { display: block; }
.dropdown-menu a {
    display: block;
    padding: 8px 16px;
    font-size: 13px;
    color: var(--text-main);
    border-radius: 0;
}
.dropdown-menu a:hover { background: var(--bg-light); color: var(--primary); }

/* 搜索框 */
.header-search {
    display: flex;
    align-items: center;
    background: var(--bg-light);
    border: 1.5px solid #e0e0e0;
    border-radius: 24px;
    padding: 6px 14px;
    gap: 8px;
    transition: var(--transition);
}
.header-search:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(45,122,58,0.1);
}
.header-search input {
    border: none;
    background: transparent;
    outline: none;
    font-size: 14px;
    width: 180px;
    color: var(--text-main);
}
.header-search button {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--primary);
    font-size: 16px;
    padding: 0;
    display: flex;
    align-items: center;
}

/* 汉堡菜单 */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 6px;
}
.hamburger span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-main);
    border-radius: 2px;
    transition: var(--transition);
}

/* ===== 搜索栏（导航下方） ===== */
.search-bar-section {
    background: var(--bg-light);
    padding: 14px 20px;
    border-bottom: 1px solid #e8f0e8;
}
.search-bar-inner {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    background: #fff;
    border: 2px solid var(--primary);
    border-radius: 32px;
    overflow: hidden;
    box-shadow: var(--shadow);
}
.search-bar-inner input {
    flex: 1;
    border: none;
    outline: none;
    padding: 12px 20px;
    font-size: 15px;
    color: var(--text-main);
}
.search-bar-inner button {
    background: var(--primary);
    color: #fff;
    border: none;
    padding: 12px 28px;
    font-size: 15px;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
}
.search-bar-inner button:hover { background: var(--primary-dark); }

/* ===== Banner ===== */
.hero-banner {
    position: relative;
    height: 580px;
    overflow: hidden;
    background: var(--bg-dark);
}
.hero-banner img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.75;
}
.hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(13,31,15,0.75) 0%, rgba(45,122,58,0.4) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 20px;
}
.hero-content { color: #fff; max-width: 800px; }
.hero-content h1 {
    font-size: clamp(32px, 5vw, 64px);
    font-weight: 900;
    letter-spacing: 4px;
    margin-bottom: 16px;
    text-shadow: 0 2px 12px rgba(0,0,0,0.4);
    line-height: 1.2;
}
.hero-content .hero-sub {
    font-size: clamp(14px, 2vw, 20px);
    opacity: 0.9;
    margin-bottom: 28px;
    line-height: 1.6;
}
.hero-content .hero-desc {
    font-size: 14px;
    opacity: 0.75;
    margin-bottom: 32px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}
.hero-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn-primary {
    background: var(--primary);
    color: #fff;
    padding: 14px 32px;
    border-radius: 32px;
    text-decoration: none;
    font-weight: 700;
    font-size: 16px;
    transition: var(--transition);
    border: 2px solid transparent;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(45,122,58,0.4); }
.btn-outline {
    background: transparent;
    color: #fff;
    padding: 14px 32px;
    border-radius: 32px;
    text-decoration: none;
    font-weight: 700;
    font-size: 16px;
    border: 2px solid #fff;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 8px;
}
.btn-outline:hover { background: #fff; color: var(--primary); transform: translateY(-2px); }

/* ===== 通用容器 ===== */
.container { max-width: 1280px; margin: 0 auto; padding: 0 20px; }
.section { padding: 70px 0; }
.section-alt { background: var(--bg-light); }
.section-dark { background: var(--bg-dark); color: var(--text-light); }

.section-header { text-align: center; margin-bottom: 50px; }
.section-header h2 {
    font-size: clamp(24px, 3.5vw, 40px);
    font-weight: 800;
    color: var(--primary-dark);
    margin-bottom: 12px;
    letter-spacing: 2px;
}
.section-dark .section-header h2 { color: var(--accent2); }
.section-header p { font-size: 16px; color: var(--text-muted); max-width: 600px; margin: 0 auto; }
.section-dark .section-header p { color: rgba(255,255,255,0.7); }
.section-line {
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    margin: 12px auto 0;
    border-radius: 2px;
}

/* ===== 统计数字 ===== */
.stats-bar {
    background: var(--primary);
    padding: 30px 0;
    color: #fff;
}
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    text-align: center;
}
.stat-item .num {
    font-size: 36px;
    font-weight: 900;
    color: var(--accent2);
    display: block;
}
.stat-item .label { font-size: 14px; opacity: 0.9; margin-top: 4px; }

/* ===== 视频卡片 ===== */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}
.video-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
}
.video-card:hover { transform: translateY(-6px); box-shadow: 0 12px 40px rgba(45,122,58,0.2); }
.video-thumb {
    position: relative;
    overflow: hidden;
    aspect-ratio: 16/9;
    background: #111;
}
.video-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.05); }
.play-btn {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.35);
    opacity: 0;
    transition: var(--transition);
}
.video-card:hover .play-btn { opacity: 1; }
.play-icon {
    width: 60px;
    height: 60px;
    background: rgba(255,255,255,0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transform: scale(0.8);
    transition: var(--transition);
}
.video-card:hover .play-icon { transform: scale(1); }
.play-icon::after {
    content: '';
    border-left: 22px solid var(--primary);
    border-top: 13px solid transparent;
    border-bottom: 13px solid transparent;
    margin-left: 4px;
}
.video-badge {
    position: absolute;
    top: 10px;
    left: 10px;
    background: var(--accent);
    color: #fff;
    font-size: 11px;
    font-weight: 700;
    padding: 3px 8px;
    border-radius: 4px;
    letter-spacing: 0.5px;
}
.video-duration {
    position: absolute;
    bottom: 8px;
    right: 8px;
    background: rgba(0,0,0,0.7);
    color: #fff;
    font-size: 12px;
    padding: 2px 7px;
    border-radius: 4px;
}
.video-info { padding: 14px 16px; }
.video-info h3 {
    font-size: 15px;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 8px;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.video-meta {
    display: flex;
    gap: 12px;
    font-size: 12px;
    color: var(--text-muted);
    flex-wrap: wrap;
}
.video-meta span { display: flex; align-items: center; gap: 3px; }
.video-tags { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 8px; }
.tag {
    background: var(--bg-light);
    color: var(--primary);
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 12px;
    font-weight: 500;
}

/* ===== 模块卡片 ===== */
.module-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 24px;
}
.module-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 28px 24px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border-top: 4px solid var(--primary);
    text-align: center;
}
.module-card:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(45,122,58,0.18); }
.module-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 28px;
}
.module-card h3 { font-size: 17px; font-weight: 700; color: var(--primary-dark); margin-bottom: 10px; }
.module-card p { font-size: 14px; color: var(--text-muted); line-height: 1.6; }

/* ===== 专家卡片 ===== */
.expert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 28px;
}
.expert-card {
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}
.expert-card:hover { transform: translateY(-4px); box-shadow: 0 12px 32px rgba(45,122,58,0.2); }
.expert-img {
    width: 100%;
    height: 220px;
    object-fit: cover;
}
.expert-info { padding: 20px; }
.expert-info h3 { font-size: 18px; font-weight: 700; color: var(--primary-dark); margin-bottom: 4px; }
.expert-role { font-size: 13px; color: var(--accent); font-weight: 600; margin-bottom: 10px; }
.expert-desc { font-size: 13px; color: var(--text-muted); line-height: 1.6; margin-bottom: 14px; }
.expert-awards { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 14px; }
.award-badge {
    background: linear-gradient(135deg, var(--accent2), #ff9800);
    color: #fff;
    font-size: 11px;
    padding: 3px 8px;
    border-radius: 12px;
    font-weight: 600;
}
.expert-btns { display: flex; gap: 10px; }
.btn-sm {
    flex: 1;
    text-align: center;
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
}
.btn-sm-primary { background: var(--primary); color: #fff; }
.btn-sm-primary:hover { background: var(--primary-dark); }
.btn-sm-outline { border: 1.5px solid var(--primary); color: var(--primary); }
.btn-sm-outline:hover { background: var(--primary); color: #fff; }

/* ===== 合作伙伴 ===== */
.partner-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 20px;
    align-items: center;
}
.partner-item {
    background: #fff;
    border-radius: var(--radius-sm);
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    transition: var(--transition);
    border: 1px solid #eee;
}
.partner-item:hover { box-shadow: var(--shadow); transform: translateY(-2px); }
.partner-logo {
    width: 80px;
    height: 50px;
    object-fit: contain;
    margin: 0 auto 8px;
    display: block;
    filter: grayscale(0.3);
    transition: var(--transition);
}
.partner-item:hover .partner-logo { filter: grayscale(0); }
.partner-name { font-size: 12px; color: var(--text-muted); font-weight: 600; }

/* ===== 用户评价 ===== */
.review-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}
.review-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary);
    transition: var(--transition);
}
.review-card:hover { transform: translateY(-3px); }
.review-stars { color: var(--accent2); font-size: 18px; margin-bottom: 12px; letter-spacing: 2px; }
.review-text { font-size: 14px; color: var(--text-main); line-height: 1.7; margin-bottom: 16px; font-style: italic; }
.review-author { display: flex; align-items: center; gap: 12px; }
.review-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 700;
    font-size: 16px;
    flex-shrink: 0;
}
.review-name { font-weight: 700; font-size: 14px; color: var(--text-main); }
.review-date { font-size: 12px; color: var(--text-muted); }

/* ===== FAQ ===== */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
    background: #fff;
    border-radius: var(--radius-sm);
    margin-bottom: 12px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    overflow: hidden;
    border: 1px solid #eee;
}
.faq-q {
    padding: 18px 20px;
    font-weight: 700;
    font-size: 15px;
    color: var(--primary-dark);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
    user-select: none;
}
.faq-q:hover { background: var(--bg-light); }
.faq-q::after { content: '+'; font-size: 20px; color: var(--primary); font-weight: 400; transition: var(--transition); }
.faq-item.open .faq-q::after { content: '−'; }
.faq-a {
    padding: 0 20px;
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
}
.faq-item.open .faq-a { max-height: 300px; padding: 0 20px 18px; }

/* ===== 联系我们 ===== */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: start;
}
.contact-info h3 { font-size: 22px; font-weight: 800; color: var(--primary-dark); margin-bottom: 20px; }
.contact-item {
    display: flex;
    gap: 14px;
    margin-bottom: 18px;
    align-items: flex-start;
}
.contact-icon {
    width: 44px;
    height: 44px;
    background: var(--bg-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
    color: var(--primary);
}
.contact-text strong { display: block; font-size: 14px; color: var(--text-main); margin-bottom: 2px; }
.contact-text span { font-size: 13px; color: var(--text-muted); }
.qr-group { display: flex; gap: 24px; flex-wrap: wrap; margin-top: 24px; }
.qr-item { text-align: center; }
.qr-item img { width: 120px; height: 120px; border-radius: 8px; border: 2px solid #eee; }
.qr-item p { font-size: 12px; color: var(--text-muted); margin-top: 6px; font-weight: 600; }

/* ===== 社区入口 ===== */
.community-entry-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
}
.entry-card {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 24px 20px;
    text-align: center;
    transition: var(--transition);
    border: 1px solid var(--border);
    cursor: pointer;
}
.entry-card:hover { background: var(--primary); transform: translateY(-4px); }
.entry-icon { font-size: 36px; margin-bottom: 12px; }
.entry-card h4 { font-size: 15px; font-weight: 700; color: var(--text-light); margin-bottom: 6px; }
.entry-card p { font-size: 12px; color: rgba(255,255,255,0.6); }

/* ===== 分享按钮 ===== */
.share-bar {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
    padding: 20px 0;
}
.share-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: 24px;
    font-size: 14px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}
.share-wechat { background: #07c160; color: #fff; }
.share-weibo { background: #e6162d; color: #fff; }
.share-douyin { background: #000; color: #fff; }
.share-bilibili { background: #00a1d6; color: #fff; }
.share-btn:hover { opacity: 0.85; transform: translateY(-2px); }

/* ===== 面包屑 ===== */
.breadcrumb {
    background: var(--bg-light);
    padding: 12px 0;
    border-bottom: 1px solid #e8f0e8;
}
.breadcrumb-inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 20px;
    font-size: 13px;
    color: var(--text-muted);
}
.breadcrumb-inner a { color: var(--primary); text-decoration: none; }
.breadcrumb-inner a:hover { text-decoration: underline; }
.breadcrumb-inner span { margin: 0 6px; }

/* ===== 页脚 ===== */
.site-footer {
    background: var(--bg-dark);
    color: rgba(255,255,255,0.8);
    padding: 60px 0 0;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    padding-bottom: 40px;
}
.footer-brand .logo-name { color: var(--accent2); font-size: 24px; margin-bottom: 12px; display: block; }
.footer-brand p { font-size: 13px; line-height: 1.7; opacity: 0.7; margin-bottom: 16px; }
.footer-col h4 { font-size: 15px; font-weight: 700; color: #fff; margin-bottom: 16px; }
.footer-col ul { list-style: none; }
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul li a { color: rgba(255,255,255,0.65); text-decoration: none; font-size: 13px; transition: var(--transition); }
.footer-col ul li a:hover { color: var(--accent2); }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding: 20px 0;
    text-align: center;
    font-size: 13px;
    color: rgba(255,255,255,0.5);
}
.footer-bottom a { color: rgba(255,255,255,0.6); text-decoration: none; }
.footer-bottom a:hover { color: var(--accent2); }

/* ===== 内页英雄区 ===== */
.page-hero {
    position: relative;
    height: 320px;
    overflow: hidden;
    background: var(--bg-dark);
}
.page-hero img { width: 100%; height: 100%; object-fit: cover; opacity: 0.55; }
.page-hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(13,31,15,0.8) 0%, rgba(45,122,58,0.5) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
}
.page-hero-content h1 { color: #fff; font-size: clamp(28px, 4vw, 48px); font-weight: 900; letter-spacing: 3px; margin-bottom: 10px; }
.page-hero-content p { color: rgba(255,255,255,0.8); font-size: 16px; }

/* ===== AI 赋能模块 ===== */
.ai-feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}
.ai-card {
    background: linear-gradient(135deg, var(--bg-card), #0a1a0c);
    border-radius: var(--radius);
    padding: 28px;
    border: 1px solid var(--border);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.ai-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
}
.ai-card:hover { transform: translateY(-4px); border-color: var(--primary); }
.ai-card h3 { font-size: 17px; font-weight: 700; color: var(--accent2); margin-bottom: 12px; }
.ai-card p { font-size: 14px; color: rgba(255,255,255,0.7); line-height: 1.7; }
.ai-icon { font-size: 40px; margin-bottom: 16px; }

/* ===== 加入社区指南 ===== */
.join-steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    counter-reset: step;
}
.join-step {
    text-align: center;
    padding: 28px 20px;
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    position: relative;
}
.join-step::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    top: -16px;
    left: 50%;
    transform: translateX(-50%);
    width: 32px;
    height: 32px;
    background: var(--primary);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 14px;
}
.join-step h4 { font-size: 15px; font-weight: 700; color: var(--primary-dark); margin-bottom: 8px; margin-top: 8px; }
.join-step p { font-size: 13px; color: var(--text-muted); line-height: 1.6; }

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
    .footer-grid { grid-template-columns: 1fr 1fr; }
    .ai-feature-grid { grid-template-columns: 1fr 1fr; }
    .join-steps { grid-template-columns: 1fr 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .main-nav { display: none; }
    .hamburger { display: flex; }
    .header-search { display: none; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-banner { height: 420px; }
    .footer-grid { grid-template-columns: 1fr; }
    .ai-feature-grid { grid-template-columns: 1fr; }
    .join-steps { grid-template-columns: 1fr 1fr; }
    .video-grid { grid-template-columns: 1fr 1fr; }
    .section { padding: 50px 0; }
    .mobile-nav {
        display: flex;
        flex-direction: column;
        background: #fff;
        box-shadow: 0 8px 24px rgba(0,0,0,0.12);
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        padding: 16px;
        gap: 4px;
        z-index: 999;
    }
    .mobile-nav a {
        padding: 12px 16px;
        border-radius: var(--radius-sm);
        color: var(--text-main);
        text-decoration: none;
        font-size: 15px;
        font-weight: 500;
    }
    .mobile-nav a:hover { background: var(--bg-light); color: var(--primary); }
}

@media (max-width: 480px) {
    .video-grid { grid-template-columns: 1fr; }
    .join-steps { grid-template-columns: 1fr; }
    .hero-btns { flex-direction: column; align-items: center; }
    .btn-primary, .btn-outline { width: 100%; max-width: 280px; justify-content: center; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ===== 懒加载占位 ===== */
img[data-src] { opacity: 0; transition: opacity 0.4s ease; }
img.loaded { opacity: 1; }

/* ===== 滚动动画 ===== */
.fade-in { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ===== 视频弹窗 ===== */
.video-modal {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.85);
    z-index: 9999;
    align-items: center;
    justify-content: center;
}
.video-modal.active { display: flex; }
.modal-inner {
    background: #000;
    border-radius: var(--radius);
    width: 90%;
    max-width: 800px;
    position: relative;
    overflow: hidden;
}
.modal-close {
    position: absolute;
    top: 12px;
    right: 16px;
    color: #fff;
    font-size: 28px;
    cursor: pointer;
    z-index: 10;
    line-height: 1;
    background: rgba(0,0,0,0.5);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none;
}
.modal-video {
    width: 100%;
    aspect-ratio: 16/9;
    background: #111;
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(255,255,255,0.6);
    font-size: 16px;
}

/* ===== 标签云 ===== */
.tag-cloud { display: flex; flex-wrap: wrap; gap: 10px; }
.tag-cloud a {
    background: var(--bg-light);
    color: var(--primary);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 13px;
    text-decoration: none;
    transition: var(--transition);
    border: 1px solid #ddd;
}
.tag-cloud a:hover { background: var(--primary); color: #fff; border-color: var(--primary); }

/* ===== 热门话题 ===== */
.hot-topics { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.hot-topic {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}
.hot-topic:hover { opacity: 0.85; transform: scale(1.03); }

/* ===== 通知条 ===== */
.notice-bar {
    background: linear-gradient(90deg, var(--primary-dark), var(--primary));
    color: #fff;
    padding: 10px 20px;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 13px;
}
.notice-label {
    background: var(--accent);
    color: #fff;
    padding: 2px 8px;
    border-radius: 4px;
    font-weight: 700;
    font-size: 12px;
    flex-shrink: 0;
}
.notice-scroll { flex: 1; overflow: hidden; white-space: nowrap; }

/* ===== 内页侧边栏 ===== */
.page-layout {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 40px;
    align-items: start;
}
.sidebar { position: sticky; top: 90px; }
.sidebar-card {
    background: #fff;
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: var(--shadow);
    margin-bottom: 24px;
}
.sidebar-card h4 { font-size: 15px; font-weight: 700; color: var(--primary-dark); margin-bottom: 14px; border-bottom: 2px solid var(--bg-light); padding-bottom: 10px; }

@media (max-width: 900px) {
    .page-layout { grid-template-columns: 1fr; }
    .sidebar { position: static; }
}

/* ===== About内容 ===== */
.about-content h3 { font-size: 18px; font-weight: 800; color: var(--primary-dark); margin: 24px 0 12px; }
.about-content p { font-size: 14px; color: var(--text-muted); line-height: 1.8; margin-bottom: 12px; }

/* ===== 移动端菜单 ===== */
.mobile-nav { display: none; }