/* ============================================================
   知识付费商城 - 前台样式表（企业灰色风格 v2）
   主色板：Tailwind gray 系，橙色 #f97316 作为 CTA/价格强调保留
   ============================================================ */
:root{
  --brand:        #4b5563;  /* 主色 gray-600 */
  --brand-dark:   #1f2937;  /* 主色深 gray-800 */
  --brand-darker: #111827;  /* 标题/深底 gray-900 */
  --text:         #1f2937;  /* 正文 */
  --text-muted:   #6b7280;  /* 辅助文字 gray-500 */
  --text-faint:   #9ca3af;  /* 更浅辅助 gray-400 */
  --bg-soft:      #f9fafb;  /* 浅灰底 gray-50 */
  --bg-softer:    #eef3f8;  /* 头部浅灰 */
  --line:         #e5e7eb;  /* 边框 gray-200 */
  --line-strong:  #d1d5db;  /* 输入边框 gray-300 */
  --accent:       #f97316;  /* 橙色 CTA 保留 */
  --accent-dark:  #ea580c;
}
*{margin:0;padding:0;box-sizing:border-box}
body{overflow-x:hidden;}
body{font-family:'Microsoft YaHei','PingFang SC',sans-serif;font-size:14px;color:#1f2937;background:#fff;line-height:1.6}
a{color:#4b5563;text-decoration:none;transition:color .2s}
a:hover{color:#1f2937}
img{max-width:100%;display:block}
.container{max-width:1200px;margin:0 auto;padding:0 16px}
.hidden{display:none!important}

/* 顶部导航：吸顶冻结，滚动时保持在视口顶部，方便随时选择菜单 */
.site-header{background:#eef3f8;position:-webkit-sticky;position:sticky;top:0;z-index:100}
.header-top{display:flex;justify-content:flex-end;align-items:center;padding:12px 30px 6px;max-width:1400px;margin:0 auto;min-height:50px}
.header-top-right{display:flex;align-items:center;gap:14px}
.header-top-right .header-search form{display:flex}
.header-top-right .header-search input{padding:8px 14px;border:1px solid #d1d5db;border-radius:20px 0 0 20px;width:170px;outline:none;font-size:15px;background:#fff;color:#1f2937}
.header-top-right .header-search input:focus{border-color:#4b5563}
.header-top-right .header-search button{padding:8px 16px;background:#4b5563;color:#fff;border:none;border-radius:0 20px 20px 0;cursor:pointer;font-size:15px;font-weight:500}
.header-top-right .header-search button:hover{background:#1f2937}
.header-top-right .btn-login{padding:7px 18px;border:1px solid #4b5563;color:#4b5563;border-radius:12px;font-size:15px;background:transparent;font-weight:500}
.header-top-right .btn-login:hover{background:#4b5563;color:#fff}
.header-top-right .btn-register{padding:7px 18px;background:#4b5563;color:#fff;border-radius:12px;font-size:15px;font-weight:500}
.header-top-right .btn-register:hover{background:#1f2937;color:#fff}
.header-top-right .user-menu{position:relative}
.header-top-right .user-menu .user-link{display:flex;align-items:center;gap:6px;color:#1f2937;cursor:pointer;padding:5px 8px;border-radius:10px}
.header-top-right .user-menu .user-link:hover{background:#e5e7eb}
.header-top-right .user-avatar{width:28px;height:28px;border-radius:50%;object-fit:cover}
.header-top-right .user-avatar.default{display:flex;align-items:center;justify-content:center;background:#4b5563;color:#fff;font-weight:600;font-size:13px}
.header-top-right .user-name{font-weight:500;color:#1f2937;font-size:15px}
.header-top-right .user-arrow{font-size:10px;color:#6b7280}
.header-top-right .user-dropdown{display:none;position:absolute;top:100%;right:0;background:#fff;min-width:170px;border:1px solid #e5e7eb;border-radius:12px;box-shadow:0 8px 24px rgba(0,0,0,.12);z-index:300;overflow:hidden;padding:5px 0}
.header-top-right .user-menu:hover .user-dropdown{display:block}
.header-top-right .user-dropdown a{display:block;padding:9px 14px;color:#1f2937;font-size:15px}
.header-top-right .user-dropdown a:hover{background:#f9fafb;color:#4b5563}
.header-top-right .user-dropdown .dropdown-divider{height:1px;background:#e5e7eb;margin:5px 0}
.header-top-right .user-dropdown .logout-link{color:#ef4444}
.header-top-right .user-dropdown .logout-link:hover{background:#fef2f2;color:#dc2626}
.header-top-right .hotline{display:flex;align-items:center;gap:8px;color:#4b5563;font-weight:600;font-size:15px;white-space:nowrap}
.header-top-right .hotline span{color:#4b5563}
.header-top-right .lang-switch{position:relative}
.header-top-right .lang-current{padding:7px 12px;border:1px solid #d1d5db;border-radius:12px;cursor:pointer;display:flex;align-items:center;gap:6px;font-size:15px;color:#1f2937;background:#fff}
.header-top-right .lang-current:hover{border-color:#4b5563}
.header-top-right .lang-globe{position:relative;display:inline-flex;align-items:center;justify-content:center;width:18px;height:18px}
.header-top-right .lang-globe::before{content:'';position:absolute;top:50%;left:50%;width:18px;height:18px;border-radius:50%;background:radial-gradient(circle,rgba(75,85,99,.3),transparent 70%);transform:translate(-50%,-50%);animation:globeGlow 2s ease-in-out infinite}
.header-top-right .lang-globe::after{content:'';position:absolute;top:50%;left:50%;width:24px;height:24px;border-radius:50%;border:2px solid transparent;border-top-color:#4b5563;border-right-color:#4b5563;transform:translate(-50%,-50%);animation:globeRotate 1.5s linear infinite}
.header-top-right .lang-globe svg{position:relative;z-index:1;width:16px;height:16px}
@keyframes globeGlow{
    0%,100%{opacity:.4;transform:translate(-50%,-50%) scale(1)}
    50%{opacity:.8;transform:translate(-50%,-50%) scale(1.3)}
}
@keyframes globeRotate{
    0%{transform:translate(-50%,-50%) rotate(0deg)}
    100%{transform:translate(-50%,-50%) rotate(360deg)}
}
.header-top-right .lang-dropdown{display:none;position:absolute;top:100%;right:0;background:#fff;min-width:110px;border:1px solid #e5e7eb;border-radius:12px;box-shadow:0 4px 16px rgba(0,0,0,.12);z-index:200;overflow:hidden}
.header-top-right .lang-switch:hover .lang-dropdown{display:block}
.header-top-right .lang-dropdown a{display:block;padding:9px 14px;color:#1f2937;font-size:15px}
.header-top-right .lang-dropdown a:hover{background:#f9fafb;color:#4b5563}
.header-inner{display:flex;align-items:flex-start;height:180px;gap:24px;padding:20px 30px 0;width:100%;max-width:1400px;margin:0 auto}
.logo{display:flex;align-items:center;gap:10px;font-size:26px;font-weight:700;color:#111827;white-space:nowrap;margin-top:18px}
.logo-img{height:80px;width:auto;max-width:200px;object-fit:contain}
.logo-icon{font-size:36px}
.main-nav{flex:0 0 auto;margin-top:18px}
.main-nav ul{display:flex;list-style:none;gap:6px;flex-wrap:nowrap}
.main-nav a{display:flex;align-items:center;gap:8px;padding:14px 22px;color:#1f2937;border-radius:12px;font-weight:600;font-size:19px;transition:all .2s;white-space:nowrap}
.main-nav a .nav-icon{width:20px;height:20px;flex-shrink:0}
.main-nav a:hover{background:#4b5563;color:#fff}
.main-nav a.active{background:#1f2937;color:#fff;position:relative;box-shadow:0 4px 12px rgba(17,24,39,.28)}
.main-nav a.active::after{content:'';position:absolute;left:18px;right:18px;bottom:5px;height:3px;border-radius:2px;background:#f97316}
.mobile-menu-btn{display:none;background:none;border:none;font-size:26px;cursor:pointer;color:#111827}
.mobile-search{display:none;flex:1;min-width:0;max-width:300px;margin:0 4px;}

/* 电话振动动画 */
@keyframes ring {
    0% { transform: rotate(0deg); }
    10% { transform: rotate(15deg); }
    20% { transform: rotate(-15deg); }
    30% { transform: rotate(15deg); }
    40% { transform: rotate(-15deg); }
    50% { transform: rotate(0deg); }
    100% { transform: rotate(0deg); }
}

/* 按钮 */
.btn{display:inline-block;padding:10px 22px;border-radius:10px;font-size:15px;cursor:pointer;border:1px solid transparent;transition:all .2s;text-align:center;font-weight:500}
.btn-primary{background:#4b5563;color:#fff}
.btn-primary:hover{background:#1f2937;color:#fff;box-shadow:0 4px 12px rgba(75,85,99,.3)}
.btn-outline{background:#fff;color:#4b5563;border-color:#4b5563}
.btn-outline:hover{background:#f3f4f6;box-shadow:0 2px 8px rgba(75,85,99,.15)}
.btn-danger{background:#ef4444;color:#fff}
.btn-danger:hover{background:#dc2626;color:#fff;box-shadow:0 4px 12px rgba(239,68,68,.3)}
.btn-white{background:#fff;color:#4b5563}
.btn-white:hover{background:#f9fafb}
.btn-block{display:block;width:100%}
.btn-lg{padding:14px 32px;font-size:16px;border-radius:12px}
.btn-sm{padding:6px 14px;font-size:14px;border-radius:8px}
.btn-disabled{background:#d1d5db;cursor:not-allowed}

/* Banner */
.banner-section{margin-bottom:0;padding-bottom:0}
.section{margin-bottom:40px}
.section:first-child{margin-top:0;padding-top:0}
.banner-container{position:relative;border-radius:0;overflow:hidden}
.banner-slide{position:absolute;top:0;left:0;width:100%;height:100%;background-size:cover;background-position:center;opacity:0;transition:opacity .6s ease-in-out;z-index:1}
.banner-slide.active{opacity:1;z-index:2}
/* banner半透明蒙版，让白色文字更清晰 */
.banner-slide::after{content:'';position:absolute;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,0.3);z-index:1;}
.banner-caption{position:relative;z-index:2;}
.banner-dots{position:absolute;bottom:16px;left:50%;transform:translateX(-50%);display:flex;gap:8px;z-index:10}
.banner-dots span{width:10px;height:10px;border-radius:50%;background:rgba(255,255,255,.5);cursor:pointer}
.banner-dots span.active{background:#fff;width:24px;border-radius:5px}

/* banner文字 */
.banner-caption{position:absolute;bottom:15%;left:8%;z-index:2;color:#fff;max-width:70%;}
.banner-caption h2{font-size:clamp(24px,4vw,48px);font-weight:700;margin-bottom:12px;text-shadow:0 2px 10px rgba(0,0,0,.3);line-height:1.3;color:#fff;}
.banner-caption p{font-size:clamp(14px,1.8vw,20px);margin-bottom:20px;text-shadow:0 2px 8px rgba(0,0,0,.3);line-height:1.6;color:#fff;}
.banner-btn{display:inline-block;padding:clamp(10px,1.5vw,14px) clamp(24px,3vw,36px);background:#f97316;color:#fff;border-radius:24px;font-size:clamp(14px,1.5vw,18px);font-weight:600;transition:all .2s;box-shadow:0 4px 12px rgba(249,115,22,.3);}
.banner-btn:hover{background:#ea580c;color:#fff;transform:translateY(-2px);box-shadow:0 6px 16px rgba(249,115,22,.4);}

/* 区块 */
.section{margin-bottom:40px}
.section-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;border-bottom:2px solid #4b5563;padding-bottom:10px}
.section-header h2{font-size:24px;color:#111827;font-weight:600}
.more-link{color:#4b5563;font-size:15px}
.two-col{display:flex;gap:24px}
.flex-2{flex:2}.flex-1{flex:1}

/* 课程卡片 */
.course-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.course-card{background:#fff;border-radius:12px;overflow:hidden;box-shadow:0 2px 12px rgba(0,0,0,.06);transition:transform .25s,box-shadow .25s;border:1px solid #e5e7eb}
.course-card:hover{transform:translateY(-6px);box-shadow:0 12px 32px rgba(75,85,99,.15)}
.course-cover{position:relative;display:block;padding-top:56.25%;background:#e5e7eb;overflow:hidden}
.course-cover img{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover;transition:transform .3s}
.course-card:hover .course-cover img{transform:scale(1.05)}
.course-type-tag{position:absolute;top:10px;left:10px;background:rgba(75,85,99,.95);color:#fff;padding:3px 10px;border-radius:12px;font-size:13px;font-weight:500}
.course-info{padding:16px}
.course-title{font-size:17px;font-weight:600;margin-bottom:8px;line-height:1.4;color:#1f2937;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;min-height:42px}
.course-title a{color:#1f2937}
.course-title a:hover{color:#f97316}
.course-teacher{font-size:16px;color:#6b7280;margin-bottom:10px}
.course-bottom{display:flex;justify-content:space-between;align-items:center}
.student-count{font-size:15px;color:#6b7280}
.price{color:#f97316;font-weight:700;font-size:16px}
.price.free{color:#f97316}
.price.vip{color:#f59e0b}
.original-price{color:#6b7280;text-decoration:line-through;font-size:14px;margin-left:6px}

/* 文章列表 */
.article-list{display:flex;flex-direction:column;gap:12px}
.article-item{display:flex;gap:12px;background:#fff;padding:12px;border-radius:8px;box-shadow:0 1px 4px rgba(0,0,0,.05)}
.article-cover{width:180px;height:120px;border-radius:6px;overflow:hidden;flex-shrink:0}
.article-cover img{width:100%;height:100%;object-fit:cover}
.article-info{flex:1}
.article-info h3{font-size:16px;margin-bottom:4px}
.article-summary{font-size:16px;color:#4b5563;margin-bottom:6px}
.article-meta{font-size:14px;color:#6b7280;display:flex;gap:16px}

/* 面包屑 */
.breadcrumb{padding:16px 0;font-size:15px;color:#6b7280}
.breadcrumb a{color:#4b5563}
.breadcrumb span{color:#1f2937}

/* 页面头部 */
.page-header{padding:20px 0}
.page-header h1{font-size:28px;color:#111827;margin-bottom:8px}
.page-header p{color:#4b5563}

/* 筛选栏 */
.filter-bar{background:#fff;padding:16px 20px;border-radius:10px;margin-bottom:20px}
.filter-row{display:flex;align-items:center;margin-bottom:10px}
.filter-row:last-child{margin-bottom:0}
.filter-label{width:60px;color:#4b5563;font-weight:500;flex-shrink:0}
.filter-links{display:flex;flex-wrap:wrap;gap:8px}
.filter-links a{padding:4px 12px;border-radius:4px;color:#4b5563;font-size:15px}
.filter-links a:hover{background:#e5e7eb}
.filter-links a.active{background:#4b5563;color:#fff}

/* 分页 */
.pager{display:flex;justify-content:center;align-items:center;gap:6px;margin:24px 0;flex-wrap:wrap}
.pager a,.pager span{padding:6px 12px;border:1px solid #d1d5db;border-radius:4px;color:#4b5563;font-size:15px;background:#fff}
.pager a:hover{border-color:#4b5563;color:#4b5563}
.pager .current{background:#4b5563;color:#fff;border-color:#4b5563}

/* 课程详情 */
.course-detail-layout{display:flex;gap:24px;margin-bottom:32px}
.detail-main{flex:1}
.detail-sidebar{width:300px;flex-shrink:0}
.detail-header{display:flex;gap:24px;background:#fff;padding:24px;border-radius:12px;margin-bottom:20px}
.detail-cover{width:320px;height:200px;border-radius:10px;overflow:hidden;flex-shrink:0;position:relative}
.detail-cover img{width:100%;height:100%;object-fit:cover}
.detail-type-tag{position:absolute;top:10px;left:10px;background:#4b5563;color:#fff;padding:4px 12px;border-radius:4px;font-size:14px}
.detail-info{flex:1}
.detail-title{font-size:24px;color:#111827;margin-bottom:8px}
.detail-subtitle{color:#4b5563;margin-bottom:12px}
.detail-meta{display:flex;gap:20px;color:#6b7280;font-size:15px;margin-bottom:16px}
.detail-teacher{display:flex;align-items:center;gap:10px;margin-bottom:16px;padding:12px;background:#f9fafb;border-radius:8px}
.teacher-avatar{width:48px;height:48px;border-radius:50%;object-fit:cover}
.detail-price-bar{display:flex;align-items:center;gap:20px;margin-bottom:12px}
.detail-price{font-size:32px;color:#ef4444;font-weight:700}
.detail-price.free{color:#f97316}
.detail-price.vip{color:#f59e0b}
.detail-price.owned{color:#10b981;font-size:20px}
.detail-original{color:#6b7280;text-decoration:line-through;font-size:16px}
.detail-actions{display:flex;gap:10px}
.detail-notice{background:#fffbeb;color:#92400e;padding:8px 12px;border-radius:6px;font-size:14px}

/* Tab */
.detail-tabs{background:#fff;border-radius:12px;overflow:hidden}
.tab-nav{display:flex;border-bottom:1px solid #e5e7eb;padding:0 20px}
.tab{padding:14px 20px;cursor:pointer;color:#4b5563;font-weight:500;border-bottom:2px solid transparent}
.tab.active{color:#4b5563;border-bottom-color:#4b5563}
.tab-content{padding:24px}
.course-intro{line-height:1.8;color:#374151}
.course-intro img{max-width:100%;border-radius:8px;margin:8px 0}

/* 章节列表 */
.chapter-list{display:flex;flex-direction:column;gap:0}
.chapter-item{display:flex;align-items:center;gap:12px;padding:12px 16px;border-bottom:1px solid #e5e7eb}
.chapter-item:hover{background:#f9fafb}
.chapter-num{width:28px;height:28px;background:#e5e7eb;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:14px;color:#4b5563;flex-shrink:0}
.chapter-type{background:#e5e7eb;color:#4b5563;padding:2px 8px;border-radius:4px;font-size:13px}
.chapter-title{flex:1;font-size:15px}
.chapter-free{background:#10b981;color:#fff;padding:2px 8px;border-radius:4px;font-size:13px}
.chapter-locked{color:#6b7280}
.chapter-play{background:#4b5563;color:#fff;padding:4px 12px;border-radius:4px;font-size:13px}
.chapter-duration{color:#6b7280;font-size:14px}

/* 评论 */
.comment-form{margin-bottom:20px}
.comment-form textarea{width:100%;padding:12px;border:1px solid #d1d5db;border-radius:8px;resize:vertical;margin-bottom:10px}
.comment-form-bottom{display:flex;justify-content:space-between;align-items:center}
.comment-item{display:flex;gap:12px;padding:16px 0;border-bottom:1px solid #e5e7eb}
.comment-avatar{width:40px;height:40px;border-radius:50%;object-fit:cover;flex-shrink:0}
.comment-avatar.default{display:flex;align-items:center;justify-content:center;background:#4b5563;color:#fff;font-weight:600}
.comment-body{flex:1}
.comment-header{display:flex;align-items:center;gap:12px;margin-bottom:6px}
.comment-header strong{color:#111827}
.comment-rating{color:#f59e0b;font-size:13px}
.comment-time{color:#6b7280;font-size:14px}
.comment-content{color:#4b5563;line-height:1.6}
.empty-text{color:#6b7280;text-align:center;padding:20px}
.login-tip{text-align:center;padding:20px;color:#4b5563}

/* 侧边栏卡片 */
.sidebar-card{background:#fff;border-radius:12px;padding:20px;margin-bottom:16px}
.sidebar-card h4{font-size:16px;margin-bottom:12px;color:#111827}
.related-courses{display:flex;flex-direction:column;gap:12px}
.course-card.small{display:flex;gap:10px}
.course-card.small .course-cover{width:100px;height:64px;padding-top:0;flex-shrink:0;border-radius:6px}
.course-card.small .course-info{padding:0;flex:1}
.course-card.small h4{font-size:14px;margin-bottom:4px}
.course-card.small .course-bottom{font-size:13px}

/* 播放页 */
.player-page{background:#000;min-height:100vh}
.player-container{max-width:1400px;margin:0 auto;display:flex;background:#fff;min-height:calc(100vh - 64px)}
.player-main{flex:1;padding:20px}
.player-box{background:#000;border-radius:8px;overflow:hidden;margin-bottom:16px;aspect-ratio:16/9}
.player-box video{width:100%;height:100%}
.audio-player-wrap{display:flex;flex-direction:column;align-items:center;padding:40px;background:linear-gradient(135deg,#111827,#1f2937)}
.audio-cover{width:200px;height:200px;border-radius:12px;overflow:hidden;margin-bottom:24px;box-shadow:0 8px 32px rgba(0,0,0,.3)}
.audio-cover img{width:100%;height:100%;object-fit:cover}
.audio-player-wrap audio{width:100%;max-width:400px}
.article-player{padding:40px;background:#fff}
.article-content{max-width:800px;margin:0 auto;line-height:2;font-size:16px;color:#1f2937}
.article-content img{max-width:100%;border-radius:8px}
.download-player{padding:60px;text-align:center}
.download-box{background:#f9fafb;padding:40px;border-radius:12px;display:inline-block}
.player-info h1{font-size:22px;margin-bottom:8px}
.player-course-title{color:#4b5563;margin-bottom:16px}
.player-actions{display:flex;gap:10px;margin-bottom:20px}
.note-section{background:#f9fafb;padding:20px;border-radius:10px;margin-top:16px}
.note-section textarea{width:100%;padding:12px;border:1px solid #d1d5db;border-radius:8px;margin-bottom:10px;resize:vertical}
.note-list{margin-top:16px}
.note-item{background:#fff;padding:12px;border-radius:8px;margin-bottom:8px}
.note-item p{color:#1f2937;margin-bottom:4px}
.note-item span{color:#6b7280;font-size:14px}

/* 播放列表侧边栏 */
.player-sidebar{width:320px;background:#f9fafb;border-left:1px solid #e5e7eb;overflow-y:auto}
.playlist-header{padding:16px 20px;border-bottom:1px solid #e5e7eb;display:flex;justify-content:space-between;align-items:center;background:#fff}
.playlist-header h3{font-size:16px}
.playlist-count{color:#6b7280;font-size:15px}
.playlist{padding:8px}
.playlist-item{display:flex;align-items:center;gap:10px;padding:10px 12px;border-radius:6px;cursor:pointer;color:#4b5563;font-size:15px}
.playlist-item:hover{background:#fff}
.playlist-item.active{background:#f3f4f6;color:#4b5563;font-weight:600}
.pl-num{width:24px;text-align:center;color:#6b7280;flex-shrink:0}
.playlist-item.active .pl-num{color:#4b5563}
.pl-title{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.pl-duration{color:#6b7280;font-size:14px;flex-shrink:0}

/* 会员中心顶部（紧凑单行，对齐全站主风格） */
.uc-header{display:flex;align-items:center;gap:24px;padding:10px 0}
.uc-header .uc-logo{display:flex;align-items:center;flex-shrink:0}
.uc-header .uc-logo .logo-img{height:36px;width:auto;max-width:150px;object-fit:contain}
.uc-header .uc-logo .logo-icon{font-size:24px}
.uc-header .uc-logo .logo-text{font-size:20px;font-weight:700;color:#111827}
.uc-header .uc-main-nav{display:flex;gap:4px}
.uc-header .uc-main-nav a{display:flex;align-items:center;gap:6px;padding:9px 18px;color:#1f2937;font-weight:600;font-size:15px;border-radius:8px;transition:all .2s}
.uc-header .uc-main-nav a:hover{background:#e2e8f0;color:#4b5563}
.uc-header .uc-main-nav .nav-icon{width:17px;height:17px}
.uc-header .uc-header-user{margin-left:auto;display:flex;align-items:center;gap:14px}
.uc-header .user-link{display:flex;align-items:center;gap:8px;color:#4b5563}
.uc-header .user-avatar{width:30px;height:30px;border-radius:50%;object-fit:cover}
.uc-header .user-avatar.default{display:flex;align-items:center;justify-content:center;background:#4b5563;color:#fff;font-weight:600;font-size:14px}
.uc-header .user-name{font-size:14px;color:#4b5563}
.uc-header .btn-logout{padding:6px 14px;border:1px solid #e5e7eb;border-radius:8px;color:#6b7280;font-size:14px;transition:all .2s}
.uc-header .btn-logout:hover{color:#dc2626;border-color:#fca5a5;background:#fef2f2}

/* 会员中心 */
.ucenter-page{background:#f9fafb}
.ucenter-container{padding:24px 0}
.ucenter-layout{display:flex;gap:24px}
.ucenter-sidebar{width:240px;flex-shrink:0}
.uc-user-card{background:#fff;border:1px solid #e5e7eb;border-radius:12px;padding:24px;text-align:center;margin-bottom:16px}
.uc-avatar{width:72px;height:72px;border-radius:50%;object-fit:cover;margin:0 auto 12px;display:block}
.uc-avatar.default{display:flex;align-items:center;justify-content:center;background:#4b5563;color:#fff;font-size:28px;font-weight:600}
.uc-user-card h3{font-size:18px;margin-bottom:8px}
.uc-vip-badge{display:inline-block;background:linear-gradient(135deg,#f97316,#fb923c);color:#fff;padding:4px 12px;border-radius:20px;font-size:13px}
.uc-upgrade-btn{display:inline-block;background:linear-gradient(135deg,#f97316,#fb923c);color:#fff;padding:6px 16px;border-radius:20px;font-size:15px;box-shadow:0 2px 8px rgba(249,115,22,.25);transition:all .2s}
.uc-upgrade-btn:hover{transform:translateY(-1px);box-shadow:0 4px 14px rgba(249,115,22,.35)}
.uc-nav{background:#fff;border:1px solid #e5e7eb;border-radius:12px;padding:8px;display:flex;flex-direction:column}
.uc-nav a{display:flex;align-items:center;gap:10px;padding:11px 14px;border-radius:8px;color:#4b5563;font-size:15px;transition:all .2s}
.uc-nav a:hover{background:#f3f4f6;color:#1f2937}
.uc-nav a.active{background:#4b5563;color:#fff;font-weight:600}
.uc-nav .uc-nav-ic{width:18px;height:18px;flex-shrink:0}
.uc-nav a.active .uc-nav-ic{color:#fb923c}
.ucenter-main{flex:1;min-width:0}
.uc-page-header{background:#fff;border:1px solid #e5e7eb;padding:20px 24px;border-radius:12px;margin-bottom:16px}
.uc-page-header h2{font-size:20px;margin-bottom:4px}
.uc-page-header p{color:#6b7280;font-size:15px}
.uc-section{background:#fff;border:1px solid #e5e7eb;padding:20px 24px;border-radius:12px;margin-bottom:16px}
.uc-section-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px}
.uc-stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-bottom:16px}
.uc-stat-card{background:#fff;border:1px solid #e5e7eb;padding:22px 16px;border-radius:12px;text-align:center;transition:all .25s}
.uc-stat-card:hover{box-shadow:0 8px 20px rgba(75,85,99,.08);transform:translateY(-2px);border-color:#d1d5db}
.stat-icon{width:48px;height:48px;margin:0 auto 12px;display:flex;align-items:center;justify-content:center;background:#f3f4f6;border-radius:12px;color:#4b5563}
.stat-icon svg{width:24px;height:24px}
.uc-stat-card:hover .stat-icon{background:#eef3f8;color:#f97316}
.stat-value{font-size:24px;font-weight:700;color:#111827}
.stat-label{color:#6b7280;font-size:15px;margin-top:4px}
.recent-list{display:flex;flex-direction:column;gap:8px}
.recent-item{display:flex;align-items:center;gap:12px;padding:12px;background:#f9fafb;border:1px solid #f3f4f6;border-radius:8px;transition:all .2s}
.recent-item:hover{border-color:#e5e7eb;background:#fff}
.recent-cover{width:80px;height:50px;border-radius:6px;object-fit:cover;flex-shrink:0}
.recent-info{flex:1}
.recent-info h4{font-size:15px;margin-bottom:2px}
.recent-info span{color:#6b7280;font-size:14px}
.recent-btn{color:#4b5563;font-size:15px;white-space:nowrap;transition:color .2s}
.recent-item:hover .recent-btn{color:#f97316}
.ucenter-page .empty-text{color:#6b7280;text-align:center;padding:24px 20px;border:1px dashed #d1d5db;border-radius:8px;background:#f9fafb}
.ucenter-page .empty-text a{color:#f97316;font-weight:500}

/* 我的课程 */
.my-courses-list{display:flex;flex-direction:column;gap:12px}
.my-course-card{display:flex;gap:16px;background:#fff;padding:16px;border-radius:12px}
.my-course-cover{position:relative;width:200px;height:120px;border-radius:8px;overflow:hidden;flex-shrink:0}
.my-course-cover img{width:100%;height:100%;object-fit:cover}
.play-overlay{position:absolute;inset:0;background:rgba(0,0,0,.5);display:flex;align-items:center;justify-content:center;color:#fff;opacity:0;transition:opacity .2s}
.my-course-cover:hover .play-overlay{opacity:1}
.my-course-info{flex:1}
.my-course-info h3{font-size:16px;margin-bottom:8px}
.my-course-meta{color:#6b7280;font-size:15px;margin-bottom:12px;display:flex;gap:16px}
.progress-bar{height:8px;background:#e5e7eb;border-radius:4px;overflow:hidden;margin-bottom:6px}
.progress-fill{height:100%;background:linear-gradient(90deg,#4b5563,#9ca3af);border-radius:4px;transition:width .3s}
.progress-text{font-size:14px;color:#6b7280}

/* 订单 */
.order-tabs{display:flex;gap:4px;margin-bottom:16px;background:#fff;padding:8px;border-radius:10px}
.order-tabs a{padding:8px 20px;border-radius:6px;color:#4b5563}
.order-tabs a.active{background:#4b5563;color:#fff}
.order-card{background:#fff;border-radius:10px;margin-bottom:12px;overflow:hidden}
.order-card-header{display:flex;justify-content:space-between;padding:12px 20px;background:#f9fafb;border-bottom:1px solid #e5e7eb;font-size:15px;color:#4b5563}
.order-status{font-weight:600}
.order-status.pending{color:#f59e0b}.order-status.paid{color:#10b981}.order-status.refunded{color:#6b7280}
.order-card-body{display:flex;justify-content:space-between;align-items:center;padding:16px 20px}
.order-product-info h4{font-size:15px;margin-bottom:4px}
.order-product-info p{color:#6b7280;font-size:16px}
.order-amount{text-align:right}
.order-amount p{margin-bottom:8px}
.order-amount strong{color:#ef4444;font-size:18px}

/* 优惠券 */
.coupons-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.coupon-card{display:flex;background:#fff;border-radius:10px;overflow:hidden;box-shadow:0 2px 8px rgba(0,0,0,.06)}
.coupon-card.used{opacity:.5}
.coupon-amount{width:120px;background:linear-gradient(135deg,#ef4444,#f87171);color:#fff;display:flex;align-items:center;justify-content:center;flex-direction:column;padding:16px}
.coupon-value{font-size:28px;font-weight:700}
.coupon-info{flex:1;padding:16px}
.coupon-info h4{font-size:15px;margin-bottom:8px}
.coupon-info p{color:#6b7280;font-size:13px;margin-bottom:4px}

/* 财务 */
.finance-overview{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-bottom:20px}
.finance-card{background:#fff;padding:24px;border-radius:12px;text-align:center}
.finance-card.primary{background:linear-gradient(135deg,#4b5563,#9ca3af);color:#fff}
.finance-label{color:#6b7280;margin-bottom:8px}
.finance-card.primary .finance-label{color:rgba(255,255,255,.8)}
.finance-value{font-size:28px;font-weight:700;margin-bottom:12px}
.recharge-box{background:#fff;padding:24px;border-radius:12px;margin-bottom:20px}
.recharge-amounts{display:flex;gap:12px;margin-bottom:16px;flex-wrap:wrap}
.recharge-amounts label{flex:1;min-width:100px;padding:16px;border:2px solid #e5e7eb;border-radius:8px;text-align:center;cursor:pointer;transition:all .2s}
.recharge-amounts label:hover{border-color:#4b5563}
.recharge-amounts input:checked+span,.recharge-amounts label:has(input:checked){border-color:#4b5563;background:#f3f4f6}

/* 表格 */
.data-table{width:100%;border-collapse:collapse}
.data-table th{background:#f9fafb;padding:12px;text-align:left;font-weight:600;color:#4b5563;border-bottom:2px solid #e5e7eb;font-size:15px}
.data-table td{padding:12px;border-bottom:1px solid #e5e7eb;font-size:15px}
.data-table tr:hover{background:#f9fafb}
.data-table .actions{white-space:nowrap}
.fin-type{padding:2px 8px;border-radius:4px;font-size:13px}
.fin-type.income{background:#d1fae5;color:#065f46}
.fin-type.expense{background:#fee2e2;color:#991b1b}
.finance-overview .income{color:#10b981}.finance-overview .expense{color:#ef4444}

/* 收藏 */
.favorites-list{display:flex;flex-direction:column;gap:12px}
.favorite-card{display:flex;gap:16px;background:#fff;padding:16px;border-radius:10px}
.fav-cover{width:160px;height:100px;border-radius:8px;overflow:hidden;flex-shrink:0}
.fav-cover img{width:100%;height:100%;object-fit:cover}
.fav-info{flex:1;min-width:0}
.fav-info h4{font-size:15px;margin-bottom:8px;overflow-wrap:break-word}
.fav-info p{color:#6b7280;font-size:16px;margin-bottom:12px}

/* 笔记 */
.notes-list{display:flex;flex-direction:column;gap:12px}
.note-card{background:#fff;padding:16px 20px;border-radius:10px;border-left:4px solid #4b5563}
.note-card-header{display:flex;justify-content:space-between;flex-wrap:wrap;gap:4px;margin-bottom:8px;font-size:15px;color:#4b5563}
.note-card-header a,.note-card-header span{min-width:0;overflow-wrap:break-word}
.note-card-content p{color:#374151;line-height:1.6}
.note-card-time{color:#6b7280;font-size:14px;margin-top:8px}

/* 消息 */
.messages-list{display:flex;flex-direction:column;gap:12px}
.message-card{background:#fff;padding:16px 20px;border-radius:10px}
.message-header{display:flex;align-items:center;gap:12px;margin-bottom:8px;flex-wrap:wrap;min-width:0}
.message-header strong{min-width:0;overflow-wrap:break-word}
.message-header span{min-width:0}
.message-type{background:#e5e7eb;color:#4b5563;padding:2px 8px;border-radius:4px;font-size:13px}
.message-time{color:#6b7280;font-size:14px;margin-left:auto}
.message-content p{color:#4b5563}

/* VIP页面 */
.vip-hero{background:linear-gradient(135deg,#111827,#1f2937);color:#fff;padding:60px 0;text-align:center}
.vip-hero h1{font-size:36px;margin-bottom:12px}
.vip-hero p{font-size:16px;color:rgba(255,255,255,.7)}
.vip-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin:-40px 0 40px;position:relative;z-index:1}
.vip-card{background:#fff;border-radius:16px;padding:32px;text-align:center;box-shadow:0 8px 32px rgba(0,0,0,.1);transition:transform .2s}
.vip-card:hover{transform:translateY(-8px)}
.vip-card.current{border:2px solid #f59e0b}
.vip-card-header{margin-bottom:20px}
.vip-card-header h3{font-size:22px;color:#111827}
.vip-badge{display:inline-block;background:#f59e0b;color:#fff;padding:2px 10px;border-radius:10px;font-size:13px;margin-top:8px}
.vip-card-price{margin-bottom:20px}
.price-item{margin-bottom:8px}
.price-item .amount{font-size:28px;font-weight:700;color:#ef4444}
.price-item .period{color:#6b7280;margin-left:4px}
.price-item.highlight{background:linear-gradient(135deg,#fef3c7,#fde68a);padding:12px;border-radius:8px;position:relative}
.price-item .tag{position:absolute;top:-8px;right:8px;background:#f59e0b;color:#fff;padding:2px 8px;border-radius:10px;font-size:12px}
.vip-card-privileges{text-align:left;margin-bottom:24px}
.vip-card-privileges ul{list-style:none}
.vip-card-privileges li{padding:6px 0;color:#4b5563;font-size:15px}
.vip-faq{background:#fff;padding:40px;border-radius:16px;margin-bottom:40px}
.vip-faq h2{font-size:24px;margin-bottom:24px;text-align:center}
.faq-item{margin-bottom:20px;padding-bottom:20px;border-bottom:1px solid #e5e7eb}
.faq-item:last-child{border-bottom:none}
.faq-item h4{font-size:16px;color:#111827;margin-bottom:8px}
.faq-item p{color:#4b5563;line-height:1.6}

/* 搜索页 */
.search-tabs{display:flex;gap:4px;margin-bottom:20px;background:#fff;padding:8px;border-radius:10px}
.search-tabs a{padding:8px 20px;border-radius:6px;color:#4b5563;font-size:15px}
.search-tabs a.active{background:#4b5563;color:#fff}
.search-section-title{font-size:18px;margin:20px 0 12px;color:#111827}
.search-article-list{display:flex;flex-direction:column;gap:12px}
.search-article-item{background:#fff;padding:16px 20px;border-radius:10px}
.search-article-item h4{margin-bottom:6px}
.search-article-item p{color:#4b5563;font-size:16px;margin-bottom:6px}
.search-article-item span{color:#6b7280;font-size:14px}

/* 认证页面 */
.auth-page{min-height:calc(100vh - 64px);display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#1f2937,#111827);padding:40px 0}
.auth-container{width:100%;max-width:420px}
.auth-box{background:#fff;padding:40px;border-radius:16px;box-shadow:0 20px 60px rgba(0,0,0,.15)}
.auth-box h2{font-size:24px;text-align:center;margin-bottom:8px;color:#111827}
.auth-subtitle{text-align:center;color:#6b7280;margin-bottom:24px}
.auth-footer{text-align:center;margin-top:20px;color:#4b5563;font-size:15px}
.login-tip{text-align:center;color:#6b7280;font-size:14px;margin-top:16px}

/* 两联卡式布局 */
.dual-card-page{min-height:calc(100vh - 64px);display:flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#f9fafb,#e5e7eb);padding:40px 16px}
.dual-card-container{width:100%;max-width:960px;display:grid;grid-template-columns:1fr 1fr;gap:0;background:#fff;border-radius:20px;overflow:hidden;box-shadow:0 20px 60px rgba(75,85,99,.15)}
.dual-card-left{background:linear-gradient(135deg,#4b5563,#1f2937);color:#fff;padding:48px 40px;display:flex;flex-direction:column;justify-content:center;position:relative;overflow:hidden}
.dual-card-left::before{content:'';position:absolute;top:-50%;right:-30%;width:300px;height:300px;background:radial-gradient(circle,rgba(249,115,22,.15),transparent 70%);border-radius:50%}
.dual-card-left h2{font-size:28px;margin-bottom:16px;position:relative;z-index:1}
.dual-card-left p{font-size:16px;line-height:1.8;color:rgba(255,255,255,.85);margin-bottom:24px;position:relative;z-index:1}
.dual-card-left .feature-list{list-style:none;position:relative;z-index:1}
.dual-card-left .feature-list li{padding:8px 0;font-size:15px;color:rgba(255,255,255,.9);display:flex;align-items:center;gap:10px}
.dual-card-left .feature-list li::before{content:'✓';color:#f97316;font-weight:700}
.dual-card-right{padding:48px 40px}
.dual-card-right h3{font-size:22px;color:#111827;margin-bottom:8px}
.dual-card-right .subtitle{color:#6b7280;margin-bottom:24px;font-size:15px}
.form-group{margin-bottom:18px}
.form-group label{display:block;font-weight:600;margin-bottom:8px;color:#1f2937;font-size:15px}
.form-group input,.form-group select,.form-group textarea{width:100%;padding:12px 16px;border:1px solid #e5e7eb;border-radius:10px;font-size:15px;outline:none;transition:border-color .2s,box-shadow .2s;box-sizing:border-box}
.form-group input:focus,.form-group select:focus,.form-group textarea:focus{border-color:#f97316;box-shadow:0 0 0 3px rgba(249,115,22,.1)}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.form-tip{font-size:14px;color:#6b7280;margin-top:6px}
.form-links{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px;font-size:14px}
.form-links a{color:#f97316}
.form-links a:hover{text-decoration:underline}
.auth-tabs{display:flex;gap:0;margin-bottom:24px;border-bottom:2px solid #e5e7eb}
.auth-tabs a{flex:1;text-align:center;padding:12px 0;color:#6b7280;font-weight:500;font-size:15px;border-bottom:2px solid transparent;margin-bottom:-2px;transition:all .2s}
.auth-tabs a.active{color:#f97316;border-bottom-color:#f97316}
.auth-tabs a:hover{color:#f97316}

/* 证书查询结果 */
.cert-result{margin-top:24px}
.cert-card{background:#fff;border:2px solid #4b5563;border-radius:14px;padding:28px;position:relative;overflow:hidden}
.cert-card::before{content:'';position:absolute;top:0;left:0;right:0;height:4px;background:linear-gradient(90deg,#f97316,#4b5563)}
.cert-status{display:flex;align-items:center;gap:14px;margin-bottom:20px;padding-bottom:16px;border-bottom:1px solid #e5e7eb}
.cert-badge{width:64px;height:64px;border:3px solid #4b5563;border-radius:50%;display:flex;align-items:center;justify-content:center;color:#4b5563;font-size:14px;font-weight:700;text-align:center;line-height:1.2;transform:rotate(-10deg);flex-shrink:0}
.cert-status-info h4{font-size:18px;color:#111827;margin-bottom:4px}
.cert-status-info p{font-size:15px;color:#6b7280}
.cert-detail-row{display:flex;justify-content:space-between;padding:10px 0;border-bottom:1px solid #f9fafb;font-size:15px}
.cert-detail-row:last-child{border-bottom:none}
.cert-detail-row .label{color:#6b7280}
.cert-detail-row .value{font-weight:600;color:#1f2937;text-align:right}
.cert-download-btn{position:absolute;top:16px;right:16px;background:#f97316;color:#fff;padding:8px 16px;border-radius:10px;font-size:15px;font-weight:600}
.cert-download-btn:hover{background:#ea580c;color:#fff}
.cert-not-found{background:#fff;border:2px solid #fecaca;border-radius:14px;padding:40px;text-align:center}
.cert-not-found .icon{font-size:48px;margin-bottom:16px}
.cert-not-found h4{color:#ef4444;font-size:20px;margin-bottom:8px}
.cert-not-found p{color:#6b7280;font-size:14px}

/* 空状态 */
.empty-state{padding:60px 20px;text-align:center;color:#6b7280}
.empty-state p{font-size:16px;margin-bottom:16px}
.empty-state .btn{margin-top:8px}

/* 表单 */
.form-group{margin-bottom:16px}
.form-group label{display:block;margin-bottom:6px;font-weight:500;color:#1f2937;font-size:15px}
.form-group input,.form-group select,.form-group textarea{width:100%;padding:10px 14px;border:1px solid #d1d5db;border-radius:8px;font-size:15px;outline:none;transition:border-color .2s;font-family:inherit}
.form-group input:focus,.form-group select:focus,.form-group textarea:focus{border-color:#4b5563}
.form-group textarea{resize:vertical}
.form-row{display:flex;gap:16px}
.form-row .form-group{flex:1}
.form-row.checkboxes{align-items:center;gap:24px}
.checkbox-label{display:flex;align-items:center;gap:6px;cursor:pointer;font-weight:normal}
.checkbox-label input{width:auto}
.required{color:#ef4444}
.forgot-link{color:#4b5563;font-size:15px}
.form-actions{display:flex;gap:12px;margin-top:20px}

/* 提示框 */
.alert{padding:12px 16px;border-radius:8px;margin-bottom:16px;font-size:15px}
.alert-error{background:#fee2e2;color:#991b1b;border:1px solid #fecaca}
.alert-success{background:#d1fae5;color:#065f46;border:1px solid #a7f3d0}

/* 空状态 */
.empty-state{text-align:center;padding:60px 20px;color:#6b7280}
.empty-state p{margin-bottom:16px;font-size:16px}

/* 文章详情页 */
.article-detail-layout{display:flex;gap:24px;margin-bottom:32px}
.article-detail-main{flex:1;background:#fff;padding:32px;border-radius:12px}
.article-detail-header{margin-bottom:24px;padding-bottom:24px;border-bottom:1px solid #e5e7eb}
.article-detail-header h1{font-size:28px;color:#111827;margin-bottom:12px;line-height:1.4}
.article-detail-meta{display:flex;gap:20px;color:#6b7280;font-size:15px}
.article-detail-summary{background:#f9fafb;padding:16px 20px;border-radius:8px;margin-bottom:24px;color:#4b5563;line-height:1.8}
.article-detail-content{line-height:2;font-size:16px;color:#1f2937}
.article-detail-content img{max-width:100%;border-radius:8px;margin:12px 0}
.article-detail-content h2,.article-detail-content h3{margin:24px 0 12px}
.article-detail-nav{display:flex;justify-content:space-between;margin-top:32px;padding-top:24px;border-top:1px solid #e5e7eb}
.article-detail-nav a{color:#4b5563}
.article-detail-sidebar{width:300px;flex-shrink:0}
.related-articles{list-style:none}
.related-articles li{display:flex;justify-content:space-between;padding:10px 0;border-bottom:1px solid #e5e7eb;font-size:15px}
.related-articles li a{color:#4b5563;flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.related-articles li span{color:#6b7280;flex-shrink:0;margin-left:8px}

/* 文章列表页 */
.article-list-page{display:flex;flex-direction:column;gap:16px;margin-bottom:24px}
.article-card{display:flex;gap:20px;background:#fff;padding:20px;border-radius:12px;box-shadow:0 2px 8px rgba(0,0,0,.05);transition:transform .2s}
.article-card:hover{transform:translateX(4px)}
.article-card-cover{width:240px;height:150px;border-radius:8px;overflow:hidden;flex-shrink:0}
.article-card-cover img{width:100%;height:100%;object-fit:cover}
.article-card-body{flex:1;display:flex;flex-direction:column}
.article-card-body h2{font-size:18px;margin-bottom:8px}
.article-card-body h2 a{color:#111827}
.article-card-summary{color:#4b5563;font-size:16px;flex:1;margin-bottom:12px;line-height:1.6}
.article-card-meta{display:flex;gap:16px;color:#6b7280;font-size:15px}

/* 支付结果 */
.pay-result{padding:60px 0;text-align:center}
.pay-result-box{background:#fff;padding:48px;border-radius:16px;display:inline-block;box-shadow:0 8px 32px rgba(0,0,0,.08)}
.pay-result-box.success .pay-result-icon{width:80px;height:80px;background:#10b981;color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:40px;margin:0 auto 20px}
.pay-result-box h2{font-size:28px;margin-bottom:16px;color:#111827}
.pay-result-box p{color:#4b5563;margin-bottom:8px}
.pay-result-actions{display:flex;gap:12px;justify-content:center;margin-top:24px}
.pay-result-note{color:#6b7280;font-size:14px;margin-top:20px}

/* 响应式 */
@media(max-width:1024px){
    .course-grid{grid-template-columns:repeat(3,1fr)}
    .two-col{flex-direction:column}
    .course-detail-layout{flex-direction:column}
    .detail-sidebar{width:100%}
    .ucenter-layout{flex-direction:column}
    .ucenter-sidebar{width:100%}
    .uc-stats-grid{grid-template-columns:repeat(2,1fr)}
    .coupons-grid{grid-template-columns:repeat(2,1fr)}
    .vip-cards{grid-template-columns:1fr;max-width:400px;margin-left:auto;margin-right:auto}
}
@media(max-width:768px){
    body{overflow-x:clip;}
    .site-header{position:-webkit-sticky;position:sticky;top:0;z-index:100;}
    .site-header.hd-fixed{position:fixed;top:0;left:0;right:0;}
    .top-bar{display:none !important;}
    .container{padding:0 10px !important;}
    .header-top{display:none !important;}
    .header-inner{display:flex !important;align-items:center !important;flex-wrap:nowrap !important;gap:10px !important;padding:12px !important;height:auto !important;width:100% !important;}
    .logo{flex-shrink:0;}
    .logo .logo-img{height:50px !important;width:auto !important;max-width:140px !important;object-fit:contain !important;}
    .main-nav{display:none !important;width:100%;order:99;}
    .main-nav.show{display:block !important;position:absolute;top:74px;left:0;right:0;background:#fff;padding:15px;box-shadow:0 4px 12px rgba(0,0,0,.15);z-index:99999 !important;}
    .main-nav.show ul{flex-direction:column;padding:0;gap:0;}
    .header-search{display:none !important;}
    .mobile-search{display:flex;}
    .mobile-search input{flex:1;min-width:0;padding:8px 14px;border:1px solid #d1d5db;border-radius:20px 0 0 20px;outline:none;font-size:15px;background:#fff;color:#1f2937;}
    .mobile-search input:focus{border-color:#4b5563;}
    .mobile-search button{padding:7px 13px;background:#4b5563;color:#fff;border:none;border-radius:0 20px 20px 0;cursor:pointer;flex-shrink:0;display:flex;align-items:center;justify-content:center;}
    .mobile-search button:hover{background:#1f2937;}
    .mobile-menu-btn{display:block !important;background:none;border:none;font-size:22px;cursor:pointer;margin-left:auto;flex-shrink:0;position:relative;z-index:100000;}
    /* 手机端banner适配：主标题+副标题+按钮精简排版 */
    .banner-caption{left:6%;right:6%;max-width:92%;bottom:14%;}
    .banner-caption p{display:-webkit-box !important;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;font-size:13px !important;margin-bottom:12px !important;line-height:1.5 !important;}
    .banner-caption h2{font-size:20px !important;margin-bottom:6px !important;}
    .banner-btn{padding:7px 18px !important;font-size:13px !important;}
    .course-grid{grid-template-columns:repeat(2,1fr)}
    .detail-header{flex-direction:column}
    .detail-cover{width:100%;height:200px}
    .player-container{flex-direction:column}
    .player-sidebar{width:100%;max-height:300px}
    .finance-overview{grid-template-columns:1fr}
    .article-card{flex-direction:column}
    .article-card-cover{width:100%;height:180px}
    .my-course-card{flex-direction:column}
    .my-course-cover{width:100%;height:180px}
}

/* ============================================================
   底部 Footer 样式
   ============================================================ */
.site-footer{
    background:#1f2937;
    color:#c2d0dc;
    margin-top:70px;
    padding:60px 0 0;
    font-size:15px;
}
.footer-top{
    display:flex;
    flex-wrap:wrap;
    gap:30px 36px;
    padding-bottom:40px;
    border-bottom:1px solid rgba(255,255,255,0.08);
}
.footer-col{
    flex:1 1 0;
    min-width:165px;
}
.footer-col:first-child,
.footer-col:last-child{
    flex-grow:1.8;
}
.footer-col h4{
    color:#fff;
    font-size:16px;
    font-weight:600;
    margin:0 0 20px;
    position:relative;
    padding-bottom:10px;
}
.footer-col h4::after{
    content:'';
    position:absolute;
    left:0;
    bottom:0;
    width:30px;
    height:2px;
    background:linear-gradient(90deg,#4b5563,#9ca3af);
    border-radius:2px;
}
.footer-col p{
    line-height:1.8;
    margin:0;
    color:#9ca3af;
    overflow-wrap:break-word;
}
.footer-links{
    display:flex;
    flex-direction:column;
    gap:10px;
}
.footer-links a{
    color:#9ca3af;
    text-decoration:none;
    transition:color .2s,padding-left .2s;
    display:inline-block;
    overflow-wrap:break-word;
}
.footer-links a:hover{
    color:#fff;
    padding-left:5px;
}
.footer-links-bar{
    padding:20px 0;
    border-bottom:1px solid rgba(255,255,255,0.08);
    display:flex;
    flex-wrap:wrap;
    align-items:center;
    gap:15px;
    font-size:14px;
}
.footer-links-bar span{
    color:#4b5563;
}
.footer-links-bar a{
    color:#9ca3af;
    text-decoration:none;
    transition:color .2s;
    overflow-wrap:break-word;
}
.footer-links-bar a:hover{
    color:#fff;
}
.footer-bottom{
    padding:25px 0;
    text-align:center;
    color:#9ca3af;
    font-size:14px;
}
.footer-bottom a{
    color:#9ca3af;
    text-decoration:none;
}
.footer-bottom a:hover{
    color:#fff;
}

/* 响应式 */
@media (max-width:768px){
    .footer-top{
        gap:26px 16px;
    }
    .footer-col{
        flex:1 1 100%;
        min-width:0;
    }
    /* 快速导航/公司介绍/帮助中心 等导航模块均分一行 */
    .footer-col.nav-col{
        flex:1 1 0;
    }
    .footer-col.nav-col h4{
        font-size:14px;
        margin-bottom:12px;
    }
    .footer-col.nav-col .footer-links{
        gap:8px;
    }
    .footer-col.nav-col .footer-links a{
        font-size:13px;
    }
}
@media (max-width:480px){
    .footer-top{
        gap:24px 10px;
    }
    .footer-col.nav-col{
        flex:1 1 0;
    }
    .site-footer{
        padding-top:40px;
    }
}

/* 课程中心页优化 */
.course-card{font-size:15px;}
.course-title{font-size:17px;line-height:1.4;}
.course-bottom{font-size:14px;}

/* 课程详情页优化 */
.detail-title{font-size:28px;line-height:1.4;}
.detail-subtitle{font-size:16px;line-height:1.6;margin-top:8px;}
.detail-meta{font-size:15px;line-height:2;}
.chapter-item{font-size:15px;line-height:2.2;}
.chapter-title{font-size:15px;}
.course-intro{font-size:16px;line-height:1.9;}
.tab-nav .tab{font-size:16px;padding:12px 20px;}

/* 章节阅读页优化 */
.container[style*="max-width:900px"]{font-size:17px;line-height:1.9;}
.container[style*="max-width:900px"] h1{font-size:26px;line-height:1.5;margin-bottom:25px;}
.container[style*="max-width:900px"] div{font-size:17px;line-height:1.9;}
.container[style*="max-width:900px"] img{margin:15px auto;border-radius:8px;}

/* ============================================================
   导航栏主题背景：精益六西格玛 Lean 6σ 六边形全景（去色转灰、极淡水印）
   ============================================================ */
/* 桌面端：导航栏整张 Lean 6σ 图拉伸铺满，header-top和header-inner共用 */
@media(min-width:769px){
.site-header{background:#eef3f8;}
.header-inner{background:transparent;}
}
/* 底边残缺美化：细密曲线波浪向下延伸，消解齐整硬底边 */
.nav-edge{position:absolute;left:0;right:0;bottom:-56px;width:100%;height:120px;display:block;pointer-events:none;z-index:20;}

/* 页面标题区：左右两侧叠加大圆弧光晕 */
.page-header{position:relative;padding:36px 0 30px;overflow:hidden;}
.page-header::before{content:'';position:absolute;right:-90px;top:-80px;width:300px;height:300px;border-radius:50%;background:radial-gradient(circle,rgba(229,231,235,.6) 0%,rgba(229,231,235,0) 66%);}
.page-header::after{content:'';position:absolute;left:-70px;bottom:-110px;width:260px;height:260px;border-radius:50%;background:radial-gradient(circle,rgba(243,244,246,.95) 0%,rgba(243,244,246,0) 66%);}
.page-header h1,.page-header p{position:relative;z-index:1;}

/* 登录/注册页：深灰底 + 半透明弧形环 */
.auth-page{position:relative;overflow:hidden;}
.auth-page::before{content:'';position:absolute;right:-110px;top:-110px;width:320px;height:320px;border-radius:50%;border:36px solid rgba(255,255,255,.07);}
.auth-page::after{content:'';position:absolute;left:-90px;bottom:-140px;width:280px;height:280px;border-radius:50%;border:26px solid rgba(255,255,255,.06);}

/* VIP页深色头图：叠加大弧形环增加层次 */
.vip-hero{position:relative;overflow:hidden;}
.vip-hero::before{content:'';position:absolute;right:-110px;top:-130px;width:360px;height:360px;border-radius:50%;border:44px solid rgba(255,255,255,.06);}
.vip-hero::after{content:'';position:absolute;left:-90px;bottom:-150px;width:320px;height:320px;border-radius:50%;border:30px solid rgba(255,255,255,.05);}
.vip-hero h1,.vip-hero p{position:relative;z-index:1;}

/* 页脚顶部：白色弧形波浪过渡 */
.site-footer{position:relative;}
.site-footer::before{content:'';position:absolute;left:0;right:0;top:-30px;height:60px;background:radial-gradient(circle at 12px 0,#fff 11px,transparent 12px);background-size:48px 60px;background-repeat:repeat-x;}

/* 手机端：导航较矮，保持白底深字，不铺深色主题背景 */
@media(max-width:768px){
    .header-inner{background:#eef3f8;}
    .logo{color:#111827 !important;}
    .main-nav a{color:#1f2937 !important;}
    .main-nav a.active{color:#fff !important;}
    .mobile-menu-btn{color:#111827 !important;}
    .lang-current{border-color:#d1d5db;color:#1f2937 !important;}
    .user-link,.user-name{color:#111827 !important;}
    .hotline{color:#4b5563 !important;}
    .hotline span{color:#4b5563 !important;}
    .hotline svg{fill:#4b5563 !important;}
    .nav-edge{display:none;}
}

/* 注册页标签切换 */
.reg-tabs{display:flex;gap:0;margin-bottom:24px;border-bottom:2px solid #e5e7eb;}
.reg-tabs a{flex:1;text-align:center;padding:12px 0;font-size:15px;font-weight:500;color:#6b7280;border-bottom:2px solid transparent;margin-bottom:-2px;transition:all .2s;}
.reg-tabs a.active{color:#4b5563;border-bottom-color:#f97316;font-weight:600;}
.reg-tabs a:hover{color:#4b5563;}

/* 验证码输入组 */
.code-input-group{display:flex;gap:10px;}
.code-input-group input{flex:1;}
.code-btn{white-space:nowrap;padding:0 16px;font-size:14px;}
.code-btn:disabled{opacity:.5;cursor:not-allowed;}

/* 第三方登录分隔线 */
.auth-divider{display:flex;align-items:center;margin:24px 0 16px;color:#9ca3af;font-size:15px;}
.auth-divider::before,.auth-divider::after{content:'';flex:1;height:1px;background:#e5e7eb;}
.auth-divider span{padding:0 14px;}

/* 第三方登录按钮 */
.auth-social{display:flex;justify-content:center;gap:12px;}
.social-btn{display:inline-flex;align-items:center;gap:8px;padding:10px 24px;border-radius:12px;font-size:15px;font-weight:500;transition:all .2s;}
.social-btn.wechat{background:#07c160;color:#fff;}
.social-btn.wechat:hover{background:#06ad56;color:#fff;transform:translateY(-1px);box-shadow:0 4px 12px rgba(7,193,96,.3);}

/* 协议勾选 */
.agreement-group{margin-bottom:20px;}
.agreement-label{display:flex;align-items:flex-start;gap:8px;font-weight:400;cursor:pointer;font-size:15px;color:#6b7280;line-height:1.6;}
.agreement-label input[type="checkbox"]{margin-top:3px;flex-shrink:0;width:16px;height:16px;accent-color:#4b5563;}
.agreement-label a{color:#f97316;}
.agreement-label a:hover{text-decoration:underline;}

/* 证书暂无电子证书 */
.cert-no-file{position:absolute;top:16px;right:16px;background:#e5e7eb;color:#6b7280;padding:6px 14px;border-radius:8px;font-size:13px;font-weight:500;}

/* VIP会员页增强 */
.vip-card{position:relative;overflow:hidden;}
.vip-card::before{content:'';position:absolute;top:0;left:0;right:0;height:4px;background:linear-gradient(90deg,#4b5563,#f97316);opacity:0;transition:opacity .3s;}
.vip-card:hover::before{opacity:1;}
.vip-card.current::before{opacity:1;background:linear-gradient(90deg,#f59e0b,#fbbf24);}
.vip-card.current{box-shadow:0 12px 40px rgba(245,158,11,.2);}
.vip-card-price .price-item{display:flex;align-items:baseline;gap:4px;justify-content:center;margin-bottom:8px;}
.vip-card-price .amount{font-size:28px;font-weight:700;color:#111827;}
.vip-card-price .period{font-size:14px;color:#6b7280;}
.vip-card-price .price-item.highlight .amount{color:#f97316;font-size:32px;}
.vip-card-price .tag{display:inline-block;background:#f97316;color:#fff;font-size:12px;padding:2px 8px;border-radius:10px;margin-left:6px;}
.vip-card-privileges li{display:flex;align-items:center;gap:8px;}
.vip-card-privileges li::before{content:'✓';color:#10b981;font-weight:700;flex-shrink:0;}
.vip-faq .faq-item{border-bottom:1px solid #e5e7eb;padding:16px 0;}
.vip-faq .faq-item:last-child{border-bottom:none;}
.vip-faq .faq-item h4{color:#111827;font-size:15px;margin-bottom:8px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;}
.vip-faq .faq-item h4::after{content:'+';color:#f97316;font-size:20px;font-weight:400;transition:transform .2s;}
.vip-faq .faq-item.open h4::after{transform:rotate(45deg);}
.vip-faq .faq-item p{color:#6b7280;font-size:15px;line-height:1.7;display:none;}
.vip-faq .faq-item.open p{display:block;}

/* 移动端通用防溢出 */
@media(max-width:768px){
    .data-table{display:block;overflow-x:auto;white-space:nowrap;-webkit-overflow-scrolling:touch;}
    .main-nav.show{max-width:100vw;}
    .coupon-card{flex-wrap:wrap;}
    .finance-overview .finance-card{min-width:0;}
    .order-card-body{flex-wrap:wrap;gap:10px;}
    .order-product-info{min-width:0;}
    .footer-links-bar{flex-wrap:wrap;}
    .footer-links-bar a{display:inline-block;max-width:100%;}
}

/* 移动端收藏卡与 flex 防撑破 */
@media(max-width:768px){
    .favorite-card{gap:12px;padding:12px;}
    .fav-cover{width:110px;height:72px;}
    .my-course-info{min-width:0;overflow-wrap:break-word;}
    .order-card-header span{min-width:0;overflow-wrap:break-word;}
    .order-product-info{min-width:0;overflow-wrap:break-word;}
    .order-card-body{flex-wrap:wrap;gap:10px;}
    .message-content{min-width:0;overflow-wrap:break-word;}
}