/* ============================================
   51视频 - 全新原创样式表
   配色方案：翡翠绿(#00C853) + 深靛蓝(#0D1B2A) + 琥珀金(#FFB300)
   ============================================ */

/* === 基础重置与变量 === */
:root {
    --clr-primary: #00C853;
    --clr-primary-dark: #009624;
    --clr-secondary: #0D1B2A;
    --clr-accent: #FFB300;
    --clr-bg: #F5F7FA;
    --clr-card: #FFFFFF;
    --clr-text: #1A2332;
    --clr-text-light: #6B7B8D;
    --clr-border: #E2E8F0;
    --clr-gradient: linear-gradient(135deg, #00C853 0%, #00BFA5 50%, #0D47A1 100%);
    --clr-hero-overlay: linear-gradient(180deg, rgba(13,27,42,0.7) 0%, rgba(13,27,42,0.3) 50%, rgba(0,200,83,0.2) 100%);
    --shadow-sm: 0 2px 8px rgba(13,27,42,0.08);
    --shadow-md: 0 4px 20px rgba(13,27,42,0.12);
    --shadow-lg: 0 8px 40px rgba(13,27,42,0.16);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    color: var(--clr-text);
    background: var(--clr-bg);
    line-height: 1.7;
    overflow-x: hidden;
}

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

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

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

/* === 头部导航 === */
.hdr-wrap {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(13,27,42,0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(0,200,83,0.15);
    transition: var(--transition);
}

.hdr-inner {
    display: flex; align-items: center; justify-content: space-between;
    max-width: 1200px; margin: 0 auto; padding: 0 20px; height: 68px;
}

.brand-logo { display: flex; align-items: center; gap: 10px; }
.brand-logo img { height: 42px; width: auto; }
.brand-logo span { font-size: 1.4rem; font-weight: 700; color: #fff; }

.main-nav { display: flex; gap: 6px; list-style: none; }
.main-nav a {
    color: rgba(255,255,255,0.8); padding: 8px 16px; border-radius: 8px;
    font-size: 0.95rem; font-weight: 500; transition: var(--transition);
}
.main-nav a:hover, .main-nav a.on { color: #fff; background: rgba(0,200,83,0.2); }

.mob-btn {
    display: none; background: none; border: none; cursor: pointer;
    width: 36px; height: 36px; position: relative;
}
.mob-btn span {
    display: block; width: 24px; height: 2px; background: #fff;
    position: absolute; left: 6px; transition: var(--transition);
}
.mob-btn span:nth-child(1) { top: 10px; }
.mob-btn span:nth-child(2) { top: 17px; }
.mob-btn span:nth-child(3) { top: 24px; }

/* === 搜索栏 === */
.srch-bar {
    background: var(--clr-secondary); padding: 12px 0;
    margin-top: 68px; border-bottom: 1px solid rgba(0,200,83,0.1);
}
.srch-wrap {
    max-width: 600px; margin: 0 auto; display: flex; gap: 8px; padding: 0 20px;
}
.srch-wrap input {
    flex: 1; padding: 10px 18px; border: 2px solid rgba(0,200,83,0.3);
    border-radius: 25px; background: rgba(255,255,255,0.08); color: #fff;
    font-size: 0.95rem; outline: none; transition: var(--transition);
}
.srch-wrap input::placeholder { color: rgba(255,255,255,0.4); }
.srch-wrap input:focus { border-color: var(--clr-primary); background: rgba(255,255,255,0.12); }
.srch-wrap button {
    padding: 10px 24px; background: var(--clr-primary); color: #fff;
    border: none; border-radius: 25px; font-weight: 600; cursor: pointer;
    transition: var(--transition);
}
.srch-wrap button:hover { background: var(--clr-primary-dark); transform: scale(1.05); }

/* === Hero区域 === */
.hero-zone {
    position: relative; min-height: 520px; display: flex; align-items: center;
    background-size: cover; background-position: center; background-attachment: fixed;
    overflow: hidden;
}
.hero-zone::before {
    content: ''; position: absolute; inset: 0;
    background: var(--clr-hero-overlay);
}
.hero-body {
    position: relative; z-index: 2; text-align: center;
    max-width: 800px; margin: 0 auto; padding: 80px 20px;
}
.hero-body h1 { font-size: 2.8rem; color: #fff; margin-bottom: 16px; line-height: 1.3; }
.hero-body h1 .hl { color: var(--clr-primary); }
.hero-body p { font-size: 1.15rem; color: rgba(255,255,255,0.85); margin-bottom: 28px; }
.hero-tags { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-bottom: 24px; }
.hero-tags span {
    padding: 6px 16px; background: rgba(0,200,83,0.2); color: #fff;
    border-radius: 20px; font-size: 0.85rem; border: 1px solid rgba(0,200,83,0.3);
}
.btn-row { display: flex; justify-content: center; gap: 14px; flex-wrap: wrap; }
.btn-g {
    padding: 12px 32px; border-radius: 25px; font-weight: 600;
    font-size: 1rem; cursor: pointer; transition: var(--transition); display: inline-block;
}
.btn-g.fill { background: var(--clr-primary); color: #fff; border: 2px solid var(--clr-primary); }
.btn-g.fill:hover { background: var(--clr-primary-dark); border-color: var(--clr-primary-dark); transform: translateY(-2px); }
.btn-g.line { background: transparent; color: #fff; border: 2px solid rgba(255,255,255,0.5); }
.btn-g.line:hover { border-color: #fff; background: rgba(255,255,255,0.1); }

/* === 通用板块 === */
.block { padding: 70px 0; }
.block.alt { background: #fff; }
.block-hd { text-align: center; margin-bottom: 48px; }
.block-hd h2 { font-size: 2rem; color: var(--clr-secondary); margin-bottom: 12px; }
.block-hd h2 .hl { color: var(--clr-primary); }
.block-hd p { font-size: 1.05rem; color: var(--clr-text-light); max-width: 600px; margin: 0 auto; }

/* === 视频卡片网格 === */
.vgrid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.vcard {
    background: var(--clr-card); border-radius: var(--radius); overflow: hidden;
    box-shadow: var(--shadow-sm); transition: var(--transition); position: relative;
}
.vcard:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.vcard-thumb {
    position: relative; padding-top: 56.25%; overflow: hidden; cursor: pointer;
}
.vcard-thumb img, .vcard-thumb video {
    position: absolute; top: 0; left: 0; width: 100%; height: 100%; object-fit: cover;
    transition: transform 0.5s ease;
}
.vcard:hover .vcard-thumb img, .vcard:hover .vcard-thumb video { transform: scale(1.08); }
.play-icon {
    position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%) scale(0.8);
    width: 56px; height: 56px; background: rgba(0,200,83,0.9); border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    opacity: 0; transition: var(--transition); z-index: 3;
}
.play-icon::after {
    content: ''; width: 0; height: 0;
    border-left: 18px solid #fff; border-top: 11px solid transparent; border-bottom: 11px solid transparent;
    margin-left: 4px;
}
.vcard:hover .play-icon { opacity: 1; transform: translate(-50%, -50%) scale(1); }
.vcard-dur {
    position: absolute; bottom: 8px; right: 8px; background: rgba(0,0,0,0.75);
    color: #fff; padding: 2px 8px; border-radius: 4px; font-size: 0.8rem; z-index: 3;
}
.vcard-info { padding: 16px; }
.vcard-info h3 { font-size: 1rem; margin-bottom: 8px; line-height: 1.4; color: var(--clr-text); }
.vcard-meta { display: flex; gap: 14px; color: var(--clr-text-light); font-size: 0.82rem; }
.vcard-meta span { display: flex; align-items: center; gap: 4px; }

/* === 专家展示 === */
.expert-row { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.expert-item {
    background: var(--clr-card); border-radius: var(--radius); padding: 28px 20px;
    text-align: center; box-shadow: var(--shadow-sm); transition: var(--transition);
}
.expert-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.expert-item img {
    width: 90px; height: 90px; border-radius: 50%; margin: 0 auto 16px;
    object-fit: cover; border: 3px solid var(--clr-primary);
}
.expert-item h4 { font-size: 1.05rem; margin-bottom: 4px; color: var(--clr-secondary); }
.expert-item .role { color: var(--clr-primary); font-size: 0.85rem; margin-bottom: 10px; }
.expert-item p { font-size: 0.88rem; color: var(--clr-text-light); margin-bottom: 14px; }
.expert-item .ebtn {
    display: inline-block; padding: 6px 18px; border: 1px solid var(--clr-primary);
    color: var(--clr-primary); border-radius: 20px; font-size: 0.82rem;
    transition: var(--transition);
}
.expert-item .ebtn:hover { background: var(--clr-primary); color: #fff; }

/* === 服务模块 === */
.svc-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.svc-card {
    background: var(--clr-card); border-radius: var(--radius); overflow: hidden;
    box-shadow: var(--shadow-sm); transition: var(--transition);
}
.svc-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.svc-card img { width: 100%; height: 200px; object-fit: cover; }
.svc-card-body { padding: 20px; }
.svc-card-body h3 { font-size: 1.1rem; margin-bottom: 8px; color: var(--clr-secondary); }
.svc-card-body p { font-size: 0.9rem; color: var(--clr-text-light); }

/* === FAQ模块 === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
    background: var(--clr-card); border-radius: var(--radius); margin-bottom: 12px;
    box-shadow: var(--shadow-sm); overflow: hidden;
}
.faq-q {
    padding: 18px 24px; cursor: pointer; display: flex;
    justify-content: space-between; align-items: center;
    font-weight: 600; font-size: 1rem; color: var(--clr-secondary);
    transition: var(--transition);
}
.faq-q:hover { color: var(--clr-primary); }
.faq-q::after { content: '+'; font-size: 1.4rem; color: var(--clr-primary); transition: var(--transition); }
.faq-item.open .faq-q::after { content: '-'; }
.faq-a { padding: 0 24px; max-height: 0; overflow: hidden; transition: all 0.4s ease; }
.faq-item.open .faq-a { padding: 0 24px 18px; max-height: 300px; }
.faq-a p { font-size: 0.92rem; color: var(--clr-text-light); line-height: 1.7; }

/* === 用户评论 === */
.rev-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.rev-card {
    background: var(--clr-card); border-radius: var(--radius); padding: 24px;
    box-shadow: var(--shadow-sm); position: relative;
}
.rev-card::before {
    content: '\201C'; position: absolute; top: 12px; left: 20px;
    font-size: 3rem; color: rgba(0,200,83,0.15); font-family: Georgia, serif;
}
.rev-stars { color: var(--clr-accent); margin-bottom: 10px; font-size: 0.9rem; }
.rev-card p { font-size: 0.92rem; color: var(--clr-text); margin-bottom: 14px; line-height: 1.7; }
.rev-user { display: flex; align-items: center; gap: 10px; }
.rev-user strong { font-size: 0.9rem; color: var(--clr-secondary); }
.rev-user span { font-size: 0.8rem; color: var(--clr-text-light); }

/* === 合作品牌 === */
.partner-wall {
    display: flex; flex-wrap: wrap; justify-content: center; gap: 30px;
    align-items: center; padding: 20px 0;
}
.partner-wall span {
    padding: 12px 24px; background: var(--clr-card); border-radius: 8px;
    box-shadow: var(--shadow-sm); font-size: 0.95rem; color: var(--clr-text-light);
    font-weight: 500;
}

/* === How-To指南 === */
.howto-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.howto-step {
    text-align: center; padding: 24px 16px;
    background: var(--clr-card); border-radius: var(--radius); box-shadow: var(--shadow-sm);
}
.howto-step .num {
    width: 48px; height: 48px; background: var(--clr-gradient); color: #fff;
    border-radius: 50%; display: flex; align-items: center; justify-content: center;
    font-size: 1.2rem; font-weight: 700; margin: 0 auto 14px;
}
.howto-step h4 { font-size: 0.95rem; margin-bottom: 8px; color: var(--clr-secondary); }
.howto-step p { font-size: 0.85rem; color: var(--clr-text-light); }

/* === 联系我们 === */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: start; }
.contact-info { }
.contact-info h3 { font-size: 1.3rem; margin-bottom: 20px; color: var(--clr-secondary); }
.contact-row { display: flex; gap: 12px; margin-bottom: 16px; align-items: flex-start; }
.contact-row .ci-label { font-weight: 600; min-width: 80px; color: var(--clr-secondary); font-size: 0.92rem; }
.contact-row .ci-val { color: var(--clr-text-light); font-size: 0.92rem; }
.qr-group { display: flex; gap: 24px; }
.qr-item { text-align: center; }
.qr-item img { width: 140px; height: 140px; border-radius: 8px; margin-bottom: 8px; }
.qr-item p { font-size: 0.82rem; color: var(--clr-text-light); }

/* === 新闻动态 === */
.news-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.news-item {
    background: var(--clr-card); border-radius: var(--radius); padding: 24px;
    box-shadow: var(--shadow-sm); transition: var(--transition);
}
.news-item:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.news-item .ndate { font-size: 0.8rem; color: var(--clr-primary); margin-bottom: 8px; }
.news-item h4 { font-size: 1rem; margin-bottom: 8px; color: var(--clr-secondary); }
.news-item p { font-size: 0.88rem; color: var(--clr-text-light); }

/* === 社交分享 === */
.share-row { display: flex; justify-content: center; gap: 16px; flex-wrap: wrap; }
.share-row a {
    padding: 10px 22px; border-radius: 25px; font-size: 0.9rem; font-weight: 500;
    color: #fff; transition: var(--transition);
}
.share-row a:hover { transform: translateY(-2px); opacity: 0.9; color: #fff; }
.share-row .s-wx { background: #07C160; }
.share-row .s-wb { background: #E6162D; }
.share-row .s-dy { background: #111; }
.share-row .s-bl { background: #00A1D6; }

/* === 页脚 === */
.ftr-wrap {
    background: var(--clr-secondary); color: rgba(255,255,255,0.7); padding: 50px 0 0;
}
.ftr-top { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; padding-bottom: 40px; }
.ftr-col h4 { color: #fff; font-size: 1rem; margin-bottom: 16px; }
.ftr-col p { font-size: 0.88rem; line-height: 1.7; margin-bottom: 8px; }
.ftr-col a { color: rgba(255,255,255,0.6); font-size: 0.88rem; display: block; margin-bottom: 8px; }
.ftr-col a:hover { color: var(--clr-primary); }
.ftr-brand { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.ftr-brand img { height: 36px; }
.ftr-brand span { color: #fff; font-size: 1.2rem; font-weight: 700; }
.ftr-bottom {
    border-top: 1px solid rgba(255,255,255,0.1); padding: 20px 0;
    text-align: center; font-size: 0.82rem;
}
.ftr-links { display: flex; justify-content: center; gap: 16px; flex-wrap: wrap; margin-top: 8px; }
.ftr-links a { color: rgba(255,255,255,0.5); font-size: 0.8rem; }
.ftr-links a:hover { color: var(--clr-primary); }

/* === 面包屑 === */
.crumb {
    padding: 14px 0; font-size: 0.85rem; color: var(--clr-text-light);
    background: #fff; border-bottom: 1px solid var(--clr-border);
    margin-top: 68px;
}
.crumb a { color: var(--clr-primary); }
.crumb span { margin: 0 6px; }

/* === 内页Hero === */
.page-hero {
    position: relative; min-height: 320px; display: flex; align-items: center;
    background-size: cover; background-position: center;
}
.page-hero::before {
    content: ''; position: absolute; inset: 0;
    background: linear-gradient(135deg, rgba(13,27,42,0.8), rgba(0,200,83,0.3));
}
.page-hero .hero-body { padding: 60px 20px; }
.page-hero h1 { font-size: 2.2rem; }

/* === 动画 === */
.fade-up { opacity: 0; transform: translateY(30px); transition: all 0.6s ease; }
.fade-up.show { opacity: 1; transform: translateY(0); }
.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }

/* === 响应式 === */
@media (max-width: 1024px) {
    .vgrid { grid-template-columns: repeat(2, 1fr); }
    .expert-row { grid-template-columns: repeat(2, 1fr); }
    .svc-grid { grid-template-columns: repeat(2, 1fr); }
    .howto-steps { grid-template-columns: repeat(2, 1fr); }
    .ftr-top { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .main-nav { 
        display: none; position: fixed; top: 68px; left: 0; right: 0;
        background: var(--clr-secondary); flex-direction: column; padding: 20px;
        border-top: 1px solid rgba(0,200,83,0.2);
    }
    .main-nav.open { display: flex; }
    .mob-btn { display: block; }
    .hero-body h1 { font-size: 1.8rem; }
    .hero-zone { min-height: 400px; }
    .vgrid { grid-template-columns: 1fr; }
    .expert-row { grid-template-columns: 1fr; }
    .svc-grid { grid-template-columns: 1fr; }
    .rev-grid { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .howto-steps { grid-template-columns: 1fr; }
    .news-row { grid-template-columns: 1fr; }
    .ftr-top { grid-template-columns: 1fr; }
    .block { padding: 40px 0; }
    .block-hd h2 { font-size: 1.5rem; }
    .page-hero { min-height: 240px; }
    .page-hero h1 { font-size: 1.6rem; }
}

@media (max-width: 480px) {
    .hdr-inner { height: 56px; }
    .srch-bar { margin-top: 56px; }
    .crumb { margin-top: 56px; }
    .brand-logo img { height: 32px; }
    .brand-logo span { font-size: 1.1rem; }
    .hero-body h1 { font-size: 1.5rem; }
    .btn-g { padding: 10px 24px; font-size: 0.9rem; }
    .qr-group { flex-direction: column; align-items: center; }
}