/* ========================================
   每日大赛视频社区 - 完整样式
   amcggmfg.cn
   ======================================== */

/* ---- CSS变量 ---- */
:root {
  --primary: #ef4444;
  --primary-dark: #dc2626;
  --secondary: #22c55e;
  --accent: #3b82f6;
  --accent2: #f97316;
  --dark: #1a1a2e;
  --dark2: #16213e;
  --dark3: #0f3460;
  --bg-light: #f8f9fc;
  --bg-card: #ffffff;
  --text: #1e293b;
  --text-secondary: #64748b;
  --border: #e2e8f0;
  --radius: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --shadow: 0 4px 24px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
  --transition: 0.25s ease;
}

/* ---- Reset ---- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:'PingFang SC','Hiragino Sans GB','Microsoft YaHei','Helvetica Neue',Arial,sans-serif;color:var(--text);background:#fff;line-height:1.6;overflow-x:hidden}
img{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none;transition:color var(--transition)}
a:hover{color:var(--primary)}
ul,ol{list-style:none}
button{cursor:pointer;border:none;background:none;font-family:inherit}
h1,h2,h3,h4,h5,h6{line-height:1.3;font-weight:700}

/* ---- 容器 ---- */
.container{max-width:1200px;margin:0 auto;padding:0 20px}

/* ---- 顶部公告栏 ---- */
.top-bar{background:var(--dark);color:rgba(255,255,255,0.85);font-size:13px;padding:8px 0;text-align:center}
.top-bar a{color:var(--accent2);font-weight:600}
.top-bar a:hover{color:#fff}

/* ---- 导航栏 ---- */
.site-header{background:#fff;border-bottom:2px solid var(--primary);position:sticky;top:0;z-index:1000;box-shadow:0 2px 12px rgba(0,0,0,0.08)}
.header-inner{max-width:1200px;margin:0 auto;padding:0 20px;display:flex;align-items:center;gap:20px;height:64px}
.site-logo{display:flex;align-items:center;gap:10px;flex-shrink:0}
.site-logo img{width:42px;height:42px;border-radius:50%;object-fit:cover}
.logo-text{font-size:22px;font-weight:900;color:var(--primary);letter-spacing:-0.5px}
.site-nav{display:flex;align-items:center;gap:4px;flex:1}
.site-nav a{padding:8px 14px;border-radius:var(--radius);font-size:14px;font-weight:600;color:var(--text);transition:all var(--transition);white-space:nowrap}
.site-nav a:hover,.site-nav a.active{background:rgba(239,68,68,0.08);color:var(--primary)}
.header-search{position:relative;display:flex;align-items:center;background:var(--bg-light);border:1.5px solid var(--border);border-radius:24px;padding:6px 14px;gap:8px;min-width:220px;transition:border-color var(--transition)}
.header-search:focus-within{border-color:var(--primary)}
.header-search input{border:none;background:transparent;outline:none;font-size:14px;color:var(--text);width:100%;min-width:0}
.header-search button{background:none;border:none;cursor:pointer;font-size:16px;color:var(--text-secondary);padding:0;flex-shrink:0}
.search-dropdown{position:absolute;top:calc(100% + 8px);left:0;right:0;background:#fff;border:1px solid var(--border);border-radius:var(--radius-lg);box-shadow:var(--shadow-lg);display:none;z-index:100;overflow:hidden}
.search-dropdown.show{display:block}
.search-dropdown-item{padding:10px 16px;font-size:13px;cursor:pointer;display:flex;align-items:center;gap:8px;transition:background var(--transition)}
.search-dropdown-item:hover{background:var(--bg-light)}
.search-dropdown-item .icon{font-size:14px}
.header-actions{display:flex;gap:8px;flex-shrink:0}
.btn-login{padding:7px 18px;border-radius:24px;border:1.5px solid var(--border);font-size:13px;font-weight:600;color:var(--text);transition:all var(--transition)}
.btn-login:hover{border-color:var(--primary);color:var(--primary)}
.btn-join{padding:7px 18px;border-radius:24px;background:var(--primary);color:#fff;font-size:13px;font-weight:700;transition:all var(--transition)}
.btn-join:hover{background:var(--primary-dark);transform:translateY(-1px)}
.hamburger{display:none;flex-direction:column;gap:5px;cursor:pointer;padding:4px}
.hamburger span{width:22px;height:2px;background:var(--text);border-radius:2px;transition:all var(--transition)}
.hamburger.active span:nth-child(1){transform:rotate(45deg) translate(5px,5px)}
.hamburger.active span:nth-child(2){opacity:0}
.hamburger.active span:nth-child(3){transform:rotate(-45deg) translate(5px,-5px)}

/* ---- Hero ---- */
.hero{position:relative;min-height:580px;display:flex;align-items:center;overflow:hidden;background:var(--dark)}
.hero-bg{position:absolute;inset:0;background:url('/images/banner_hero.jpg') center/cover no-repeat;opacity:0.25}
.hero-overlay{position:absolute;inset:0;background:linear-gradient(135deg,rgba(26,26,46,0.95) 0%,rgba(15,52,96,0.85) 100%)}
.hero-content{position:relative;z-index:1;max-width:1200px;margin:0 auto;padding:60px 20px;display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center;width:100%}
.eyebrow{display:flex;align-items:center;gap:8px;font-size:13px;color:rgba(255,255,255,0.65);margin-bottom:16px;font-weight:600}
.eyebrow .dot{width:6px;height:6px;background:var(--primary);border-radius:50%;animation:pulse 2s infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:0.4}}
.hero-title{font-size:48px;font-weight:900;color:#fff;line-height:1.15;margin-bottom:16px}
.hero-title .highlight{color:var(--primary)}
.hero-desc{font-size:15px;color:rgba(255,255,255,0.7);line-height:1.8;margin-bottom:28px;max-width:480px}
.hero-stats{display:flex;gap:32px;margin-bottom:32px}
.hero-stat .num{font-size:28px;font-weight:900;color:#fff}
.hero-stat .num span{font-size:16px;color:rgba(255,255,255,0.6)}
.hero-stat .label{font-size:12px;color:rgba(255,255,255,0.5);margin-top:2px}
.hero-btns{display:flex;gap:12px;flex-wrap:wrap}
.hero-visual{display:flex;flex-direction:column;gap:12px}
.hero-card{background:rgba(255,255,255,0.08);border:1px solid rgba(255,255,255,0.12);border-radius:var(--radius-lg);overflow:hidden;backdrop-filter:blur(10px);transition:transform var(--transition)}
.hero-card:hover{transform:translateY(-4px)}
.hero-card img{width:100%;height:120px;object-fit:cover}
.hero-card-info{padding:10px 14px}
.hero-card-info .title{font-size:13px;font-weight:700;color:#fff;margin-bottom:4px}
.hero-card-info .meta{font-size:11px;color:rgba(255,255,255,0.5);display:flex;gap:12px}

/* ---- 统计栏 ---- */
.stats-bar{background:var(--dark);padding:28px 0}
.stats-grid{max-width:1200px;margin:0 auto;padding:0 20px;display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.stat-item{text-align:center}
.stat-item .num{font-size:32px;font-weight:900;color:#fff}
.stat-item .num span{font-size:18px;color:var(--primary)}
.stat-item .label{font-size:13px;color:rgba(255,255,255,0.5);margin-top:4px}

/* ---- 通用Section ---- */
.section{padding:64px 0}
.section-sm{padding:40px 0}
.section-header{display:flex;justify-content:space-between;align-items:flex-end;margin-bottom:36px;gap:16px}
.section-title{font-size:28px;font-weight:800;color:var(--dark);margin-bottom:8px}
.section-title span{color:var(--primary)}
.section-subtitle{font-size:15px;color:var(--text-secondary);max-width:560px}
.more-link{font-size:14px;font-weight:600;color:var(--primary);white-space:nowrap;transition:gap var(--transition)}
.more-link:hover{color:var(--primary-dark)}
.tag-badge{display:inline-flex;align-items:center;gap:6px;padding:5px 14px;border-radius:24px;font-size:12px;font-weight:700;margin-bottom:10px}
.tag-badge.red{background:rgba(239,68,68,0.1);color:var(--primary)}
.tag-badge.blue{background:rgba(59,130,246,0.1);color:var(--accent)}
.tag-badge.green{background:rgba(34,197,94,0.1);color:var(--secondary)}
.tag-badge.orange{background:rgba(249,115,22,0.1);color:var(--accent2)}

/* ---- 弹幕 ---- */
.danmaku-bar{background:rgba(239,68,68,0.06);border:1px solid rgba(239,68,68,0.15);border-radius:24px;padding:8px 20px;overflow:hidden;white-space:nowrap}
.danmaku-text{font-size:13px;color:var(--primary);font-weight:600;animation:scroll-left 8s linear infinite}
@keyframes scroll-left{0%{transform:translateX(100%)}100%{transform:translateX(-100%)}}

/* ---- 筛选标签 ---- */
.filter-tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:28px}
.filter-tab{padding:7px 18px;border-radius:24px;font-size:13px;font-weight:600;color:var(--text-secondary);background:var(--bg-light);border:1.5px solid var(--border);transition:all var(--transition);cursor:pointer}
.filter-tab.active,.filter-tab:hover{background:var(--primary);color:#fff;border-color:var(--primary)}

/* ---- 视频卡片 ---- */
.video-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.video-grid-3{grid-template-columns:repeat(3,1fr)}
.video-card{background:var(--bg-card);border-radius:var(--radius-lg);overflow:hidden;border:1px solid var(--border);transition:all var(--transition);cursor:pointer}
.video-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-lg);border-color:transparent}
.video-thumb{position:relative;overflow:hidden;aspect-ratio:16/9}
.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)}
.video-play-btn{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,0);transition:background var(--transition)}
.video-card:hover .video-play-btn{background:rgba(0,0,0,0.4)}
.play-icon{width:48px;height:48px;background:rgba(255,255,255,0.95);border-radius:50%;display:flex;align-items:center;justify-content:center;opacity:0;transform:scale(0.8);transition:all var(--transition)}
.play-icon::after{content:'';border-style:solid;border-width:10px 0 10px 18px;border-color:transparent transparent transparent var(--primary);margin-left:4px}
.video-card:hover .play-icon{opacity:1;transform:scale(1)}
.video-tag{position:absolute;top:10px;left:10px;padding:3px 10px;border-radius:12px;font-size:11px;font-weight:800;color:#fff;background:var(--primary)}
.video-duration{position:absolute;bottom:8px;right:8px;background:rgba(0,0,0,0.75);color:#fff;font-size:11px;font-weight:700;padding:2px 8px;border-radius:4px}
.video-info{padding:14px}
.video-title{font-size:13px;font-weight:700;color:var(--dark);line-height:1.5;margin-bottom:8px;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.video-meta{display:flex;align-items:center;gap:8px;margin-bottom:6px}
.video-meta .author{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--text-secondary)}
.video-meta .author img{width:20px;height:20px;border-radius:50%;object-fit:cover}
.video-stats{display:flex;gap:12px;font-size:12px;color:var(--text-secondary)}

/* ---- 功能卡片 ---- */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.feature-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:24px;transition:all var(--transition)}
.feature-card:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:var(--primary)}
.feature-icon{width:48px;height:48px;border-radius:var(--radius-lg);display:flex;align-items:center;justify-content:center;font-size:22px;margin-bottom:16px}
.feature-icon.red{background:rgba(239,68,68,0.1)}
.feature-icon.blue{background:rgba(59,130,246,0.1)}
.feature-icon.green{background:rgba(34,197,94,0.1)}
.feature-icon.orange{background:rgba(249,115,22,0.1)}
.feature-icon.purple{background:rgba(168,85,247,0.1)}
.feature-icon.cyan{background:rgba(6,182,212,0.1)}
.feature-title{font-size:16px;font-weight:700;color:var(--dark);margin-bottom:8px}
.feature-desc{font-size:13px;color:var(--text-secondary);line-height:1.7}

/* ---- 图片网格 ---- */
.photo-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.photo-item{position:relative;border-radius:var(--radius-lg);overflow:hidden;aspect-ratio:4/3;cursor:pointer}
.photo-item img{width:100%;height:100%;object-fit:cover;transition:transform 0.4s ease}
.photo-item:hover img{transform:scale(1.08)}
.photo-overlay{position:absolute;inset:0;background:linear-gradient(to top,rgba(0,0,0,0.7) 0%,transparent 60%);display:flex;align-items:flex-end;padding:16px;opacity:0;transition:opacity var(--transition)}
.photo-item:hover .photo-overlay{opacity:1}
.photo-overlay span{color:#fff;font-size:14px;font-weight:700}

/* ---- AI功能区 ---- */
.ai-feature-grid{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center}
.ai-feature-img{border-radius:var(--radius-xl);overflow:hidden;box-shadow:var(--shadow-lg)}
.ai-feature-img img{width:100%;height:360px;object-fit:cover}
.ai-feature-list{display:flex;flex-direction:column;gap:20px;margin-top:24px}
.ai-feature-item{display:flex;gap:16px;align-items:flex-start}
.ai-feature-item .icon{width:44px;height:44px;background:linear-gradient(135deg,var(--primary),var(--accent));border-radius:var(--radius-lg);display:flex;align-items:center;justify-content:center;font-size:20px;flex-shrink:0}
.ai-feature-item .content h4{font-size:15px;font-weight:700;color:var(--dark);margin-bottom:4px}
.ai-feature-item .content p{font-size:13px;color:var(--text-secondary);line-height:1.7}

/* ---- 专家卡片 ---- */
.expert-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.expert-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);overflow:hidden;transition:all var(--transition)}
.expert-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
.expert-avatar{width:100%;height:180px;object-fit:cover}
.expert-body{padding:16px}
.expert-name{font-size:16px;font-weight:800;color:var(--dark);margin-bottom:4px}
.expert-role{font-size:12px;color:var(--primary);font-weight:600;margin-bottom:8px}
.expert-desc{font-size:12px;color:var(--text-secondary);line-height:1.6;margin-bottom:12px}
.expert-awards{display:flex;flex-wrap:wrap;gap:4px;margin-bottom:12px}
.award-tag{padding:3px 10px;background:rgba(239,68,68,0.08);color:var(--primary);border-radius:12px;font-size:11px;font-weight:600}
.expert-btns{display:flex;gap:8px}
.btn-sm{padding:6px 14px;border-radius:20px;font-size:12px;font-weight:700;transition:all 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(--border);color:var(--text-secondary)}
.btn-sm.outline:hover{border-color:var(--primary);color:var(--primary)}

/* ---- 合作伙伴 ---- */
.partners-section{padding:48px 0;background:var(--bg-light)}
.partners-grid{display:grid;grid-template-columns:repeat(6,1fr);gap:16px}
.partner-item{background:#fff;border:1px solid var(--border);border-radius:var(--radius-lg);padding:16px 12px;text-align:center;font-size:13px;font-weight:700;color:var(--text-secondary);transition:all var(--transition)}
.partner-item:hover{border-color:var(--primary);color:var(--primary);transform:translateY(-2px)}

/* ---- How-To步骤 ---- */
.how-to-steps{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;position:relative}
.how-to-steps::before{content:'';position:absolute;top:32px;left:10%;right:10%;height:2px;background:linear-gradient(to right,var(--primary),var(--accent));z-index:0}
.step-item{text-align:center;position:relative;z-index:1;background:#fff;padding:24px 16px;border-radius:var(--radius-lg);border:1px solid var(--border);transition:all var(--transition)}
.step-item:hover{transform:translateY(-4px);box-shadow:var(--shadow);border-color:var(--primary)}
.step-num{width:56px;height:56px;background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:22px;font-weight:900;margin:0 auto 16px}
.step-title{font-size:15px;font-weight:700;color:var(--dark);margin-bottom:8px}
.step-desc{font-size:13px;color:var(--text-secondary);line-height:1.6}

/* ---- 联系区域 ---- */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:40px}
.contact-info h3{font-size:22px;font-weight:800;color:var(--dark);margin-bottom:20px}
.contact-item{display:flex;gap:14px;align-items:flex-start;margin-bottom:16px}
.contact-item .icon{width:40px;height:40px;background:rgba(239,68,68,0.08);border-radius:var(--radius);display:flex;align-items:center;justify-content:center;font-size:18px;flex-shrink:0}
.contact-item .label{font-size:12px;color:var(--text-secondary);margin-bottom:2px}
.contact-item .value{font-size:14px;font-weight:600;color:var(--dark)}
.community-links{display:flex;flex-direction:column;gap:8px}
.community-link{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--text-secondary)}
.community-link .dot{width:6px;height:6px;background:var(--primary);border-radius:50%;flex-shrink:0}
.qrcode-grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.qrcode-item{text-align:center;background:var(--bg-light);border-radius:var(--radius-lg);padding:16px}
.qrcode-item img{width:100px;height:100px;object-fit:cover;border-radius:var(--radius);margin:0 auto 10px}
.qr-label{font-size:13px;font-weight:700;color:var(--dark)}
.qr-sub{font-size:11px;color:var(--text-secondary)}

/* ---- FAQ ---- */
.faq-list{display:flex;flex-direction:column;gap:12px}
.faq-item{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);overflow:hidden;transition:all var(--transition)}
.faq-item.open{border-color:var(--primary)}
.faq-question{padding:18px 20px;display:flex;align-items:center;gap:12px;cursor:pointer;font-size:15px;font-weight:700;color:var(--dark);transition:background var(--transition)}
.faq-question:hover{background:var(--bg-light)}
.q-icon{width:28px;height:28px;background:var(--primary);color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:900;flex-shrink:0}
.faq-question .arrow{margin-left:auto;font-size:12px;color:var(--text-secondary);transition:transform var(--transition)}
.faq-item.open .faq-question .arrow{transform:rotate(180deg)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height 0.4s ease}
.faq-item.open .faq-answer{max-height:300px}
.faq-answer p{padding:0 20px 18px 60px;font-size:14px;color:var(--text-secondary);line-height:1.8}

/* ---- 用户评价 ---- */
.reviews-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.review-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:20px;transition:all var(--transition)}
.review-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.review-stars{display:flex;gap:2px;margin-bottom:10px}
.review-stars span{color:#f59e0b;font-size:14px}
.review-text{font-size:13px;color:var(--text-secondary);line-height:1.7;margin-bottom:14px}
.review-author{display:flex;align-items:center;gap:10px}
.review-avatar{width:36px;height:36px;background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:14px;font-weight:700;flex-shrink:0}
.review-name{font-size:13px;font-weight:700;color:var(--dark)}
.review-date{font-size:11px;color:var(--text-secondary)}

/* ---- 标签云 ---- */
.tag-cloud{display:flex;flex-wrap:wrap;gap:8px}
.tag-cloud-item{padding:5px 14px;background:var(--bg-light);border:1px solid var(--border);border-radius:20px;font-size:12px;font-weight:600;color:var(--text-secondary);transition:all var(--transition);cursor:pointer}
.tag-cloud-item:hover{background:rgba(239,68,68,0.08);border-color:var(--primary);color:var(--primary)}

/* ---- 通知栏 ---- */
.notice-bar{background:rgba(59,130,246,0.06);border:1px solid rgba(59,130,246,0.2);border-radius:var(--radius-lg);padding:16px 20px;display:flex;gap:12px;align-items:flex-start;margin-bottom:36px;font-size:14px;color:var(--text-secondary);line-height:1.7}
.notice-bar .icon{font-size:18px;flex-shrink:0;margin-top:1px}

/* ---- 面包屑 ---- */
.breadcrumb{display:flex;align-items:center;gap:8px;padding:12px 0;font-size:13px;color:var(--text-secondary)}
.breadcrumb a{color:var(--text-secondary)}
.breadcrumb a:hover{color:var(--primary)}
.breadcrumb .sep{color:var(--border)}
.breadcrumb .current{color:var(--text);font-weight:600}

/* ---- 页面Hero ---- */
.page-hero{background:linear-gradient(135deg,var(--dark) 0%,var(--dark3) 100%);padding:60px 20px;text-align:center}
.page-hero h1{font-size:36px;font-weight:900;color:#fff;margin-bottom:12px}
.page-hero p{font-size:15px;color:rgba(255,255,255,0.65);max-width:560px;margin:0 auto}

/* ---- 分享栏 ---- */
.share-bar{background:var(--bg-light);border-top:1px solid var(--border);border-bottom:1px solid var(--border);padding:12px 0}
.share-inner{max-width:1200px;margin:0 auto;padding:0 20px;display:flex;align-items:center;gap:16px}
.share-label{font-size:13px;font-weight:600;color:var(--text-secondary)}
.share-btns{display:flex;gap:8px}
.share-btn{padding:6px 16px;border-radius:20px;font-size:12px;font-weight:700;border:1.5px solid var(--border);color:var(--text-secondary);transition:all var(--transition)}
.share-btn:hover{border-color:var(--primary);color:var(--primary)}

/* ---- 页脚 ---- */
.site-footer{background:var(--dark);color:rgba(255,255,255,0.7);padding:48px 0 0}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:40px;padding-bottom:40px}
.footer-brand .logo-wrap{display:flex;align-items:center;gap:10px;margin-bottom:14px}
.footer-brand .logo-wrap span{font-size:18px;font-weight:800;color:#fff}
.footer-brand p{font-size:13px;line-height:1.8;margin-bottom:16px}
.footer-col h4{font-size:14px;font-weight:700;color:#fff;margin-bottom:14px}
.footer-col ul li{margin-bottom:8px}
.footer-col ul li a{font-size:13px;color:rgba(255,255,255,0.55);transition:color var(--transition)}
.footer-col ul li a:hover{color:var(--primary)}
.footer-bottom{max-width:1200px;margin:0 auto;padding:16px 20px;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px}
.footer-copy{font-size:12px;color:rgba(255,255,255,0.4)}
.footer-copy a{color:rgba(255,255,255,0.55)}
.footer-copy a:hover{color:var(--primary)}
.footer-links{display:flex;gap:16px}
.footer-links a{font-size:12px;color:rgba(255,255,255,0.4)}
.footer-links a:hover{color:var(--primary)}
.update-time{font-size:12px;color:rgba(255,255,255,0.35)}

/* ---- 按钮 ---- */
.btn-primary{display:inline-flex;align-items:center;gap:8px;padding:12px 28px;background:var(--primary);color:#fff;border-radius:28px;font-size:14px;font-weight:700;transition:all var(--transition);border:none;cursor:pointer}
.btn-primary:hover{background:var(--primary-dark);transform:translateY(-2px);box-shadow:0 8px 24px rgba(239,68,68,0.35);color:#fff}
.btn-outline-white{display:inline-flex;align-items:center;gap:8px;padding:12px 28px;border:2px solid rgba(255,255,255,0.3);color:#fff;border-radius:28px;font-size:14px;font-weight:700;transition:all var(--transition);background:transparent;cursor:pointer}
.btn-outline-white:hover{border-color:#fff;background:rgba(255,255,255,0.1);color:#fff}

/* ---- 返回顶部 ---- */
.back-to-top{position:fixed;bottom:24px;right:24px;width:44px;height:44px;background:var(--primary);color:#fff;border-radius:50%;font-size:18px;display:flex;align-items:center;justify-content:center;opacity:0;transform:translateY(20px);transition:all var(--transition);z-index:999;box-shadow:0 4px 16px rgba(239,68,68,0.4)}
.back-to-top.show{opacity:1;transform:translateY(0)}
.back-to-top:hover{background:var(--primary-dark);transform:translateY(-2px)}

/* ---- 模态框 ---- */
.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,0.85);z-index:9999;display:flex;align-items:center;justify-content:center;opacity:0;pointer-events:none;transition:opacity var(--transition)}
.modal-overlay.show{opacity:1;pointer-events:all}
.modal-content{background:var(--dark);border-radius:var(--radius-xl);width:90%;max-width:640px;position:relative;overflow:hidden}
.modal-close{position:absolute;top:16px;right:16px;width:32px;height:32px;background:rgba(255,255,255,0.1);color:#fff;border-radius:50%;font-size:16px;display:flex;align-items:center;justify-content:center;z-index:1;transition:background var(--transition)}
.modal-close:hover{background:rgba(255,255,255,0.2)}
.modal-video{background:rgba(0,0,0,0.5);min-height:280px;display:flex;align-items:center;justify-content:center}

/* ---- 淡入动画 ---- */
.fade-in{opacity:0;transform:translateY(20px);transition:opacity 0.6s ease,transform 0.6s ease}
.fade-in.visible{opacity:1;transform:translateY(0)}

/* ---- 响应式 ---- */
@media (max-width:1100px){
  .video-grid{grid-template-columns:repeat(3,1fr)}
  .expert-grid{grid-template-columns:repeat(2,1fr)}
  .reviews-grid{grid-template-columns:repeat(2,1fr)}
  .partners-grid{grid-template-columns:repeat(4,1fr)}
}

@media (max-width:900px){
  .hero-content{grid-template-columns:1fr}
  .hero-visual{display:none}
  .hero-title{font-size:36px}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .feature-grid{grid-template-columns:repeat(2,1fr)}
  .ai-feature-grid{grid-template-columns:1fr}
  .ai-feature-img{display:none}
  .contact-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
  .how-to-steps{grid-template-columns:repeat(2,1fr)}
  .how-to-steps::before{display:none}
  .video-grid{grid-template-columns:repeat(2,1fr)}
  .video-grid-3{grid-template-columns:repeat(2,1fr)}
  .photo-grid{grid-template-columns:repeat(2,1fr)}
  .partners-grid{grid-template-columns:repeat(3,1fr)}
}

@media (max-width:640px){
  .site-nav{display:none;position:fixed;top:64px;left:0;right:0;background:#fff;border-bottom:2px solid var(--primary);flex-direction:column;padding:16px;gap:4px;z-index:999;box-shadow:var(--shadow-lg)}
  .site-nav.mobile-open{display:flex}
  .site-nav a{padding:12px 16px;border-radius:var(--radius);font-size:15px}
  .hamburger{display:flex}
  .header-search{display:none}
  .header-actions{display:none}
  .hero-title{font-size:28px}
  .hero-stats{gap:16px}
  .hero-stat .num{font-size:22px}
  .section{padding:40px 0}
  .section-title{font-size:22px}
  .video-grid{grid-template-columns:repeat(1,1fr)}
  .video-grid-3{grid-template-columns:1fr}
  .feature-grid{grid-template-columns:1fr}
  .expert-grid{grid-template-columns:1fr}
  .reviews-grid{grid-template-columns:1fr}
  .how-to-steps{grid-template-columns:1fr}
  .photo-grid{grid-template-columns:1fr}
  .partners-grid{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .section-header{flex-direction:column;align-items:flex-start}
  .footer-bottom{flex-direction:column;text-align:center}
  .share-bar{display:none}
  .page-hero h1{font-size:26px}
}