/* =============================================
   51吃瓜 - 主样式文件
   品牌色：西瓜红 #E8394A / 西瓜绿 #3DAA62 / 奶油白 #FFF8F0
   字体：系统中文字体栈
   ============================================= */

/* ---- CSS变量 ---- */
:root {
  --color-primary:   #E8394A;
  --color-secondary: #3DAA62;
  --color-accent:    #FFB347;
  --color-dark:      #1A1A2E;
  --color-mid:       #2D2D44;
  --color-light:     #FFF8F0;
  --color-gray:      #F5F5F5;
  --color-text:      #333344;
  --color-muted:     #888899;
  --color-border:    #E8E8F0;
  --radius-sm:       6px;
  --radius-md:       12px;
  --radius-lg:       20px;
  --radius-xl:       32px;
  --shadow-sm:       0 2px 8px rgba(232,57,74,0.08);
  --shadow-md:       0 6px 24px rgba(232,57,74,0.14);
  --shadow-lg:       0 16px 48px rgba(26,26,46,0.18);
  --transition:      0.3s cubic-bezier(0.4,0,0.2,1);
  --font-main:       'PingFang SC','Microsoft YaHei','Hiragino Sans GB',sans-serif;
  --container-w:     1200px;
}

/* ---- Reset ---- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;font-size:16px}
body{font-family:var(--font-main);color:var(--color-text);background:#fff;line-height:1.7;overflow-x:hidden}
img{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration:none}
ul,ol{list-style:none}
button{cursor:pointer;border:none;background:none;font-family:inherit}
input,textarea,select{font-family:inherit}

/* ---- 干扰标签隐藏 ---- */
.cg-noise{display:none!important;visibility:hidden!important;position:absolute!important;width:0!important;height:0!important;overflow:hidden!important;opacity:0!important;pointer-events:none!important}

/* ---- 滚动进度条 ---- */
#scroll-bar{position:fixed;top:0;left:0;width:0%;height:3px;background:linear-gradient(90deg,var(--color-primary),var(--color-accent));z-index:9999;transition:width 0.1s}

/* ---- 容器 ---- */
.container{max-width:var(--container-w);margin:0 auto;padding:0 20px}

/* ---- 顶部公告栏 ---- */
.top-bar{background:linear-gradient(90deg,var(--color-dark),var(--color-mid));color:#fff;font-size:13px;padding:7px 0;text-align:center}
.top-bar a{color:var(--color-accent);margin:0 8px}
.top-bar span{opacity:.8;margin:0 6px}

/* ---- 头部导航 ---- */
.site-header{position:sticky;top:0;z-index:1000;background:#fff;border-bottom:2px solid var(--color-border);box-shadow:var(--shadow-sm)}
.header-inner{display:flex;align-items:center;gap:20px;padding:12px 0;flex-wrap:wrap}
.site-logo{display:flex;align-items:center;gap:10px;flex-shrink:0}
.site-logo img{width:44px;height:44px;border-radius:var(--radius-sm);object-fit:contain}
.logo-text{font-size:22px;font-weight:800;background:linear-gradient(135deg,var(--color-primary),var(--color-accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;letter-spacing:-0.5px}
.logo-sub{font-size:11px;color:var(--color-muted);display:block;margin-top:-3px}

/* 导航菜单 */
.nav-menu{display:flex;align-items:center;gap:4px;flex:1;flex-wrap:wrap}
.nav-menu a{padding:8px 14px;border-radius:var(--radius-sm);font-size:14px;font-weight:500;color:var(--color-text);transition:var(--transition);white-space:nowrap;position:relative}
.nav-menu a:hover,.nav-menu a.active{color:var(--color-primary);background:rgba(232,57,74,0.07)}
.nav-menu a.nav-hot::after{content:'热';background:var(--color-primary);color:#fff;font-size:10px;padding:1px 4px;border-radius:3px;margin-left:4px;vertical-align:middle}

/* 搜索框 */
.header-search{display:flex;align-items:center;gap:8px}
.search-wrap{position:relative;display:flex;align-items:center}
.search-wrap input{width:200px;padding:8px 40px 8px 14px;border:1.5px solid var(--color-border);border-radius:var(--radius-xl);font-size:13px;outline:none;transition:var(--transition);background:var(--color-gray)}
.search-wrap input:focus{border-color:var(--color-primary);background:#fff;width:240px}
.search-btn{position:absolute;right:10px;color:var(--color-muted);font-size:16px;transition:var(--transition)}
.search-btn:hover{color:var(--color-primary)}
.search-dropdown{position:absolute;top:calc(100% + 8px);left:0;width:100%;background:#fff;border:1.5px solid var(--color-border);border-radius:var(--radius-md);box-shadow:var(--shadow-md);padding:10px;display:none;z-index:200}
.search-dropdown.open{display:block}
.search-tags{display:flex;flex-wrap:wrap;gap:6px}
.search-tags span{font-size:12px;color:var(--color-muted);padding:3px 8px;background:var(--color-gray);border-radius:20px;cursor:pointer;transition:var(--transition)}
.search-tags span:hover{background:var(--color-primary);color:#fff}

/* 汉堡菜单 */
.hamburger{display:none;flex-direction:column;gap:5px;padding:6px;cursor:pointer}
.hamburger span{display:block;width:22px;height:2px;background:var(--color-text);border-radius:2px;transition:var(--transition)}

/* ---- 面包屑 ---- */
.breadcrumb{padding:10px 0;font-size:13px;color:var(--color-muted)}
.breadcrumb a{color:var(--color-muted)}
.breadcrumb a:hover{color:var(--color-primary)}
.breadcrumb span{margin:0 6px}

/* ---- Hero区 ---- */
.hero-section{position:relative;overflow:hidden;min-height:520px;display:flex;align-items:center}
.hero-bg{position:absolute;inset:0;background-size:cover;background-position:center;background-repeat:no-repeat}
.hero-overlay{position:absolute;inset:0;background:linear-gradient(135deg,rgba(26,26,46,0.82) 0%,rgba(232,57,74,0.45) 60%,rgba(61,170,98,0.3) 100%)}
.hero-content{position:relative;z-index:2;padding:60px 0;max-width:640px}
.hero-badge{display:inline-flex;align-items:center;gap:6px;background:rgba(255,179,71,0.2);border:1px solid var(--color-accent);color:var(--color-accent);padding:5px 14px;border-radius:20px;font-size:13px;margin-bottom:18px}
.hero-badge::before{content:'🍉';font-size:16px}
.hero-title{font-size:clamp(28px,5vw,52px);font-weight:900;color:#fff;line-height:1.2;margin-bottom:16px}
.hero-title span{color:var(--color-accent)}
.hero-desc{font-size:16px;color:rgba(255,255,255,0.85);margin-bottom:28px;line-height:1.8}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-bottom:36px}
.btn-primary{display:inline-flex;align-items:center;gap:8px;padding:13px 28px;background:linear-gradient(135deg,var(--color-primary),#c0392b);color:#fff;border-radius:var(--radius-xl);font-size:15px;font-weight:700;box-shadow:var(--shadow-md);transition:var(--transition)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 28px rgba(232,57,74,0.4)}
.btn-outline{display:inline-flex;align-items:center;gap:8px;padding:12px 26px;border:2px solid rgba(255,255,255,0.6);color:#fff;border-radius:var(--radius-xl);font-size:15px;font-weight:600;transition:var(--transition)}
.btn-outline:hover{background:rgba(255,255,255,0.15);border-color:#fff}
.btn-ghost{display:inline-flex;align-items:center;gap:8px;padding:10px 22px;color:var(--color-primary);border:1.5px solid var(--color-primary);border-radius:var(--radius-xl);font-size:14px;font-weight:600;transition:var(--transition)}
.btn-ghost:hover{background:var(--color-primary);color:#fff}
.hero-stats{display:flex;gap:28px;flex-wrap:wrap}
.stat-item{text-align:center}
.stat-item .num{font-size:26px;font-weight:900;color:var(--color-accent)}
.stat-item .label{font-size:12px;color:rgba(255,255,255,0.7);margin-top:2px}

/* ---- 通用区块 ---- */
.section-gap{padding:72px 0}
.section-gap-sm{padding:48px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:clamp(22px,3.5vw,36px);font-weight:900;color:var(--color-dark);margin-bottom:12px;position:relative;display:inline-block}
.section-title h2::after{content:'';display:block;width:48px;height:4px;background:linear-gradient(90deg,var(--color-primary),var(--color-accent));border-radius:2px;margin:10px auto 0}
.section-title p{font-size:15px;color:var(--color-muted);max-width:560px;margin:0 auto}
.title-line{display:inline-block;width:40px;height:4px;background:var(--color-primary);border-radius:2px;vertical-align:middle;margin-right:10px}

/* ---- 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-md);overflow:hidden;box-shadow:var(--shadow-sm);transition:var(--transition);cursor:pointer}
.video-card:hover{transform:translateY(-6px);box-shadow:var(--shadow-md)}
.video-thumb{position:relative;aspect-ratio:16/9;overflow:hidden;background:var(--color-dark)}
.video-thumb img{width:100%;height:100%;object-fit:cover;transition:transform 0.4s}
.video-card:hover .video-thumb img{transform:scale(1.06)}
.play-btn{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,0);transition:background 0.3s;opacity:0}
.video-card:hover .play-btn{opacity:1;background:rgba(0,0,0,0.38)}
.play-icon{width:52px;height:52px;background:linear-gradient(135deg,var(--color-primary),var(--color-accent));border-radius:50%;display:flex;align-items:center;justify-content:center;transform:scale(0.8);transition:transform 0.3s}
.video-card:hover .play-icon{transform:scale(1)}
.play-icon::after{content:'';border-left:18px solid #fff;border-top:11px solid transparent;border-bottom:11px solid transparent;margin-left:4px}
.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-tag{position:absolute;top:8px;left:8px;background:var(--color-primary);color:#fff;font-size:11px;padding:2px 8px;border-radius:4px;font-weight:600}
.video-info{padding:14px}
.video-title{font-size:15px;font-weight:700;color:var(--color-dark);margin-bottom:8px;line-height:1.4;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.video-meta{display:flex;align-items:center;gap:10px;font-size:12px;color:var(--color-muted)}
.video-stats{display:flex;gap:12px;font-size:12px;color:var(--color-muted);margin-top:6px}
.video-stats span::before{margin-right:3px}

/* ---- 功能特色卡片 ---- */
.feature-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:20px}
.feature-card{padding:28px 22px;border-radius:var(--radius-md);background:#fff;border:1.5px solid var(--color-border);transition:var(--transition);text-align:center}
.feature-card:hover{border-color:var(--color-primary);box-shadow:var(--shadow-md);transform:translateY(-4px)}
.feature-icon{width:60px;height:60px;margin:0 auto 16px;border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;font-size:28px;background:linear-gradient(135deg,rgba(232,57,74,0.1),rgba(255,179,71,0.1))}
.feature-title{font-size:16px;font-weight:700;color:var(--color-dark);margin-bottom:8px}
.feature-desc{font-size:13px;color:var(--color-muted);line-height:1.6}

/* ---- 专家卡片 ---- */
.expert-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:24px}
.expert-card{background:#fff;border-radius:var(--radius-md);overflow:hidden;box-shadow:var(--shadow-sm);transition:var(--transition)}
.expert-card:hover{transform:translateY(-5px);box-shadow:var(--shadow-md)}
.expert-photo{position:relative;height:200px;overflow:hidden;background:linear-gradient(135deg,var(--color-dark),var(--color-mid))}
.expert-photo img{width:100%;height:100%;object-fit:cover}
.expert-badge{position:absolute;top:12px;right:12px;background:var(--color-primary);color:#fff;font-size:11px;padding:3px 10px;border-radius:20px;font-weight:600}
.expert-info{padding:18px}
.expert-name{font-size:18px;font-weight:800;color:var(--color-dark);margin-bottom:4px}
.expert-role{font-size:13px;color:var(--color-primary);font-weight:600;margin-bottom:8px}
.expert-desc{font-size:13px;color:var(--color-muted);line-height:1.6;margin-bottom:12px}
.expert-awards{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:14px}
.award-tag{font-size:11px;padding:3px 9px;background:rgba(61,170,98,0.1);color:var(--color-secondary);border-radius:20px;border:1px solid rgba(61,170,98,0.3)}
.expert-actions{display:flex;gap:8px}
.expert-actions a{flex:1;text-align:center;padding:8px;border-radius:var(--radius-sm);font-size:13px;font-weight:600;transition:var(--transition)}
.expert-actions a:first-child{background:var(--color-primary);color:#fff}
.expert-actions a:last-child{border:1.5px solid var(--color-border);color:var(--color-text)}
.expert-actions a:hover{opacity:.85}

/* ---- 评价卡片 ---- */
.review-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:20px}
.review-card{background:#fff;border-radius:var(--radius-md);padding:22px;border:1.5px solid var(--color-border);transition:var(--transition)}
.review-card:hover{border-color:var(--color-accent);box-shadow:var(--shadow-sm)}
.review-stars{color:var(--color-accent);font-size:16px;margin-bottom:10px}
.review-text{font-size:14px;color:var(--color-text);line-height:1.7;margin-bottom:14px;font-style:italic}
.review-author{display:flex;align-items:center;gap:10px}
.author-avatar{width:38px;height:38px;border-radius:50%;background:linear-gradient(135deg,var(--color-primary),var(--color-accent));display:flex;align-items:center;justify-content:center;color:#fff;font-weight:700;font-size:14px;flex-shrink:0}
.author-name{font-size:14px;font-weight:700;color:var(--color-dark)}
.author-meta{font-size:12px;color:var(--color-muted)}

/* ---- FAQ ---- */
.faq-list{max-width:760px;margin:0 auto}
.faq-item{border:1.5px solid var(--color-border);border-radius:var(--radius-md);margin-bottom:12px;overflow:hidden;transition:var(--transition)}
.faq-item.open{border-color:var(--color-primary)}
.faq-question{display:flex;align-items:center;justify-content:space-between;padding:16px 20px;cursor:pointer;font-size:15px;font-weight:600;color:var(--color-dark);transition:var(--transition)}
.faq-question:hover{color:var(--color-primary)}
.faq-item.open .faq-question{color:var(--color-primary);background:rgba(232,57,74,0.04)}
.faq-arrow{width:20px;height:20px;border-radius:50%;background:var(--color-gray);display:flex;align-items:center;justify-content:center;font-size:12px;transition:transform 0.3s;flex-shrink:0}
.faq-item.open .faq-arrow{transform:rotate(180deg);background:var(--color-primary);color:#fff}
.faq-answer{max-height:0;overflow:hidden;transition:max-height 0.35s ease}
.faq-answer p{padding:0 20px 16px;font-size:14px;color:var(--color-muted);line-height:1.8}

/* ---- AI赋能区 ---- */
.ai-section{background:linear-gradient(135deg,var(--color-dark) 0%,var(--color-mid) 100%);color:#fff;position:relative;overflow:hidden}
.ai-section::before{content:'';position:absolute;inset:0;background:url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Ccircle cx='30' cy='30' r='4'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E")}
.ai-grid{display:grid;grid-template-columns:1fr 1fr;gap:48px;align-items:center}
.ai-img-wrap{border-radius:var(--radius-lg);overflow:hidden;box-shadow:var(--shadow-lg)}
.ai-features{display:flex;flex-direction:column;gap:20px}
.ai-feature-item{display:flex;gap:16px;align-items:flex-start}
.ai-icon{width:48px;height:48px;border-radius:var(--radius-md);background:linear-gradient(135deg,var(--color-primary),var(--color-accent));display:flex;align-items:center;justify-content:center;font-size:22px;flex-shrink:0}
.ai-feature-item h4{font-size:16px;font-weight:700;color:#fff;margin-bottom:5px}
.ai-feature-item p{font-size:13px;color:rgba(255,255,255,0.7);line-height:1.6}

/* ---- 社区区 ---- */
.community-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:16px}
.community-card{background:#fff;border-radius:var(--radius-md);padding:20px;text-align:center;border:1.5px solid var(--color-border);transition:var(--transition);cursor:pointer}
.community-card:hover{border-color:var(--color-secondary);transform:translateY(-3px);box-shadow:var(--shadow-sm)}
.community-icon{font-size:36px;margin-bottom:10px}
.community-title{font-size:15px;font-weight:700;color:var(--color-dark);margin-bottom:6px}
.community-count{font-size:12px;color:var(--color-muted)}

/* ---- 合作品牌 ---- */
.partner-logos{display:flex;flex-wrap:wrap;justify-content:center;gap:20px;align-items:center}
.partner-logo{padding:12px 24px;background:var(--color-gray);border-radius:var(--radius-md);font-size:14px;font-weight:600;color:var(--color-muted);transition:var(--transition)}
.partner-logo:hover{background:var(--color-primary);color:#fff}

/* ---- How-To步骤 ---- */
.how-to-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:20px}
.step-card{text-align:center;padding:24px 18px;border-radius:var(--radius-md);background:#fff;border:1.5px solid var(--color-border);transition:var(--transition)}
.step-card:hover{border-color:var(--color-primary);box-shadow:var(--shadow-sm)}
.step-num{width:44px;height:44px;border-radius:50%;background:linear-gradient(135deg,var(--color-primary),var(--color-accent));color:#fff;font-size:18px;font-weight:900;display:flex;align-items:center;justify-content:center;margin:0 auto 14px}
.step-title{font-size:15px;font-weight:700;color:var(--color-dark);margin-bottom:8px}
.step-desc{font-size:13px;color:var(--color-muted);line-height:1.6}

/* ---- 联系区 ---- */
.contact-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:20px}
.contact-card{background:#fff;border-radius:var(--radius-md);padding:24px;border:1.5px solid var(--color-border);transition:var(--transition)}
.contact-card:hover{border-color:var(--color-primary);box-shadow:var(--shadow-sm)}
.contact-icon{font-size:32px;margin-bottom:12px}
.contact-label{font-size:12px;color:var(--color-muted);margin-bottom:4px;text-transform:uppercase;letter-spacing:0.5px}
.contact-value{font-size:15px;font-weight:600;color:var(--color-dark)}
.qr-row{display:flex;gap:20px;justify-content:center;flex-wrap:wrap;margin-top:24px}
.qr-item{text-align:center}
.qr-item img{width:120px;height:120px;border-radius:var(--radius-md);border:2px solid var(--color-border)}
.qr-item p{font-size:12px;color:var(--color-muted);margin-top:6px}

/* ---- 分享栏 ---- */
.share-bar{display:flex;align-items:center;gap:12px;flex-wrap:wrap;padding:20px 0;border-top:1.5px solid var(--color-border)}
.share-label{font-size:13px;color:var(--color-muted);font-weight:600}
.share-btn{display:inline-flex;align-items:center;gap:6px;padding:7px 16px;border-radius:var(--radius-xl);font-size:13px;font-weight:600;transition:var(--transition);border:1.5px solid var(--color-border)}
.share-btn:hover{transform:translateY(-2px);box-shadow:var(--shadow-sm)}
.share-btn.wx{border-color:#07C160;color:#07C160}
.share-btn.wb{border-color:#E6162D;color:#E6162D}
.share-btn.dy{border-color:#000;color:#000}
.share-btn.bili{border-color:#00A1D6;color:#00A1D6}

/* ---- 页脚 ---- */
.site-footer{background:var(--color-dark);color:rgba(255,255,255,0.8);padding:56px 0 0}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:40px;margin-bottom:40px}
.footer-brand .logo-text{font-size:20px;color:#fff;-webkit-text-fill-color:#fff}
.footer-desc{font-size:13px;color:rgba(255,255,255,0.55);line-height:1.8;margin:12px 0 16px}
.tag-cloud{display:flex;flex-wrap:wrap;gap:6px}
.tag-cloud a{font-size:11px;padding:3px 9px;background:rgba(255,255,255,0.08);color:rgba(255,255,255,0.6);border-radius:20px;transition:var(--transition)}
.tag-cloud a:hover{background:var(--color-primary);color:#fff}
.footer-col h4{font-size:14px;font-weight:700;color:#fff;margin-bottom:16px;padding-bottom:8px;border-bottom:1px solid rgba(255,255,255,0.1)}
.footer-col ul li{margin-bottom:8px}
.footer-col ul li a{font-size:13px;color:rgba(255,255,255,0.55);transition:var(--transition)}
.footer-col ul li a:hover{color:var(--color-accent)}
.footer-bottom{border-top:1px solid rgba(255,255,255,0.1);padding:18px 0;display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:10px}
.footer-copy{font-size:13px;color:rgba(255,255,255,0.4)}
.update-time{font-size:12px;color:rgba(255,255,255,0.35)}
.footer-links{display:flex;gap:16px}
.footer-links a{font-size:12px;color:rgba(255,255,255,0.4);transition:var(--transition)}
.footer-links a:hover{color:var(--color-accent)}

/* ---- 返回顶部 ---- */
.back-top{position:fixed;bottom:28px;right:24px;width:44px;height:44px;background:var(--color-primary);color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:18px;box-shadow:var(--shadow-md);opacity:0;pointer-events:none;transition:var(--transition);z-index:500}
.back-top.visible{opacity:1;pointer-events:auto}
.back-top:hover{background:var(--color-dark);transform:translateY(-3px)}

/* ---- 视频模态框 ---- */
.video-modal{position:fixed;inset:0;background:rgba(0,0,0,0.88);z-index:2000;display:flex;align-items:center;justify-content:center;opacity:0;pointer-events:none;transition:opacity 0.3s}
.video-modal.open{opacity:1;pointer-events:auto}
.modal-inner{background:var(--color-dark);border-radius:var(--radius-lg);padding:24px;max-width:760px;width:90%;position:relative}
.modal-close{position:absolute;top:12px;right:16px;font-size:22px;color:rgba(255,255,255,0.6);cursor:pointer;transition:var(--transition)}
.modal-close:hover{color:#fff}
.modal-video{width:100%;aspect-ratio:16/9;background:#000;border-radius:var(--radius-md);display:flex;align-items:center;justify-content:center;color:rgba(255,255,255,0.4);font-size:14px}

/* ---- 内页Hero ---- */
.page-hero{background:linear-gradient(135deg,var(--color-dark),var(--color-mid));padding:56px 0;text-align:center;color:#fff}
.page-hero h1{font-size:clamp(24px,4vw,42px);font-weight:900;margin-bottom:12px}
.page-hero p{font-size:15px;color:rgba(255,255,255,0.7);max-width:560px;margin:0 auto}

/* ---- 过滤栏 ---- */
.filter-bar{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:28px}
.filter-btn{padding:7px 18px;border-radius:var(--radius-xl);font-size:13px;font-weight:600;border:1.5px solid var(--color-border);color:var(--color-text);transition:var(--transition);cursor:pointer}
.filter-btn:hover,.filter-btn.active{background:var(--color-primary);color:#fff;border-color:var(--color-primary)}

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

/* ---- Toast ---- */
.cg-toast{position:fixed;bottom:80px;left:50%;transform:translateX(-50%) translateY(20px);background:var(--color-dark);color:#fff;padding:10px 22px;border-radius:var(--radius-xl);font-size:14px;opacity:0;pointer-events:none;transition:all 0.3s;z-index:3000}
.cg-toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* ---- 响应式 ---- */
@media(max-width:1024px){
  .ai-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:768px){
  .header-inner{padding:10px 0}
  .nav-menu{display:none;flex-direction:column;position:absolute;top:100%;left:0;right:0;background:#fff;border-top:1px solid var(--color-border);padding:12px;box-shadow:var(--shadow-md);z-index:100}
  .nav-menu.open{display:flex}
  .hamburger{display:flex}
  .search-wrap input{width:160px}
  .hero-section{min-height:400px}
  .hero-content{padding:40px 0}
  .hero-stats{gap:16px}
  .video-grid{grid-template-columns:repeat(auto-fill,minmax(240px,1fr))}
  .footer-grid{grid-template-columns:1fr}
  .footer-bottom{flex-direction:column;text-align:center}
  .ai-grid{grid-template-columns:1fr}
}
@media(max-width:480px){
  .hero-actions{flex-direction:column}
  .btn-primary,.btn-outline{justify-content:center}
  .video-grid{grid-template-columns:1fr}
  .expert-grid{grid-template-columns:1fr}
  .review-grid{grid-template-columns:1fr}
  .qr-row{gap:12px}
}