/* =============================================
   丝瓜视频丝瓜视频平台 - 主样式文件
   品牌: 丝瓜视频 | 域名: aLLnizi.cn
   设计风格: 自然绿意 + 现代简洁
   ============================================= */

/* ---- 基础重置 ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
  color: #1a2e1a;
  background: #f8faf5;
  line-height: 1.7;
}
a { color: #2e7d32; text-decoration: none; transition: color .25s; }
a:hover { color: #1b5e20; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

/* ---- 容器 ---- */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section { padding: 70px 0; }
.section-alt { background: #eef5e8; }

/* ---- 颜色变量 ---- */
:root {
  --green-dark:  #1b5e20;
  --green-main:  #2e7d32;
  --green-mid:   #388e3c;
  --green-light: #81c784;
  --green-pale:  #e8f5e9;
  --gold:        #f9a825;
  --text-dark:   #1a2e1a;
  --text-mid:    #3e5c3e;
  --text-light:  #6a8f6a;
  --white:       #ffffff;
  --shadow:      0 4px 20px rgba(30,80,30,.12);
  --radius:      12px;
}

/* =============================================
   顶部导航
   ============================================= */
.site-header {
  position: sticky; top: 0; z-index: 1000;
  background: rgba(255,255,255,.96);
  backdrop-filter: blur(8px);
  border-bottom: 2px solid var(--green-light);
  box-shadow: 0 2px 12px rgba(30,80,30,.08);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 68px;
}
.logo-wrap { display: flex; align-items: center; gap: 10px; }
.logo-wrap img { width: 44px; height: 44px; border-radius: 50%; object-fit: cover; }
.logo-text { font-size: 1.5rem; font-weight: 800; color: var(--green-dark); letter-spacing: .04em; }
.logo-text span { color: var(--gold); }

.main-nav { display: flex; gap: 4px; }
.main-nav a {
  padding: 8px 14px; border-radius: 8px;
  font-size: .92rem; font-weight: 600; color: var(--text-mid);
  transition: background .2s, color .2s;
}
.main-nav a:hover, .main-nav a.active {
  background: var(--green-pale); color: var(--green-dark);
}

.header-right { display: flex; align-items: center; gap: 12px; }
.btn-join {
  background: var(--green-main); color: #fff;
  padding: 8px 20px; border-radius: 24px;
  font-size: .88rem; font-weight: 700;
  transition: background .2s, transform .15s;
}
.btn-join:hover { background: var(--green-dark); color: #fff; transform: translateY(-1px); }

/* ---- 搜索框 ---- */
.search-bar-wrap {
  background: var(--green-dark);
  padding: 12px 0;
}
.search-bar-inner {
  display: flex; align-items: center; justify-content: center; gap: 10px;
}
.search-input {
  width: 480px; max-width: 90vw;
  padding: 10px 18px; border-radius: 24px;
  border: 2px solid var(--green-light);
  font-size: .95rem; background: #fff;
  outline: none; transition: border-color .2s;
}
.search-input:focus { border-color: var(--gold); }
.search-btn {
  background: var(--gold); color: var(--green-dark);
  border: none; padding: 10px 24px; border-radius: 24px;
  font-size: .95rem; font-weight: 700; cursor: pointer;
  transition: background .2s, transform .15s;
}
.search-btn:hover { background: #f57f17; transform: translateY(-1px); }
.search-tip { color: rgba(255,255,255,.7); font-size: .82rem; }

/* =============================================
   Hero Banner
   ============================================= */
.hero {
  position: relative; overflow: hidden;
  min-height: 560px;
  display: flex; align-items: center;
}
.hero-bg {
  position: absolute; inset: 0;
  background-size: cover; background-position: center;
  filter: brightness(.55);
}
.hero-overlay {
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(27,94,32,.7) 0%, rgba(0,0,0,.3) 100%);
}
.hero-content {
  position: relative; z-index: 2;
  max-width: 700px; padding: 60px 0;
}
.hero-tag {
  display: inline-block;
  background: var(--gold); color: var(--green-dark);
  padding: 4px 14px; border-radius: 20px;
  font-size: .82rem; font-weight: 700; margin-bottom: 18px;
}
.hero h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900; color: #fff; line-height: 1.2;
  margin-bottom: 18px; text-shadow: 0 2px 12px rgba(0,0,0,.4);
}
.hero h1 em { color: var(--green-light); font-style: normal; }
.hero p {
  font-size: 1.08rem; color: rgba(255,255,255,.9);
  margin-bottom: 32px; max-width: 580px; line-height: 1.8;
}
.hero-btns { display: flex; gap: 14px; flex-wrap: wrap; }
.btn-primary {
  background: var(--green-main); color: #fff;
  padding: 13px 32px; border-radius: 28px;
  font-size: 1rem; font-weight: 700;
  box-shadow: 0 4px 16px rgba(46,125,50,.4);
  transition: background .2s, transform .15s, box-shadow .2s;
}
.btn-primary:hover { background: var(--green-dark); color: #fff; transform: translateY(-2px); box-shadow: 0 6px 20px rgba(46,125,50,.5); }
.btn-outline {
  border: 2px solid rgba(255,255,255,.8); color: #fff;
  padding: 13px 32px; border-radius: 28px;
  font-size: 1rem; font-weight: 700;
  transition: background .2s, border-color .2s;
}
.btn-outline:hover { background: rgba(255,255,255,.15); color: #fff; }

.hero-stats {
  display: flex; gap: 32px; margin-top: 40px; flex-wrap: wrap;
}
.hero-stat { text-align: center; }
.hero-stat .num { font-size: 1.8rem; font-weight: 900; color: var(--gold); display: block; }
.hero-stat .lbl { font-size: .82rem; color: rgba(255,255,255,.8); }

/* =============================================
   通用标题
   ============================================= */
.section-title {
  text-align: center; margin-bottom: 48px;
}
.section-title h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800; color: var(--green-dark);
  margin-bottom: 10px;
}
.section-title h2 span { color: var(--green-mid); }
.section-title p { color: var(--text-light); font-size: .98rem; max-width: 560px; margin: 0 auto; }
.title-line {
  width: 60px; height: 4px; border-radius: 2px;
  background: linear-gradient(90deg, var(--green-main), var(--gold));
  margin: 12px auto 0;
}

/* =============================================
   视频卡片
   ============================================= */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.video-card {
  background: #fff; border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
  transition: transform .25s, box-shadow .25s;
  cursor: pointer;
}
.video-card:hover { transform: translateY(-6px); box-shadow: 0 12px 36px rgba(30,80,30,.18); }
.video-thumb {
  position: relative; overflow: hidden;
  aspect-ratio: 16/9; background: #c8e6c9;
}
.video-thumb img {
  width: 100%; height: 100%; object-fit: cover;
  transition: transform .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 .25s;
  opacity: 0;
}
.video-card:hover .play-btn { opacity: 1; background: rgba(0,0,0,.35); }
.play-btn svg {
  width: 56px; height: 56px; fill: #fff;
  filter: drop-shadow(0 2px 8px rgba(0,0,0,.5));
  transform: scale(.85); transition: transform .25s;
}
.video-card:hover .play-btn svg { transform: scale(1); }
.video-duration {
  position: absolute; bottom: 8px; right: 10px;
  background: rgba(0,0,0,.7); color: #fff;
  font-size: .75rem; padding: 2px 7px; border-radius: 4px;
}
.video-tag {
  position: absolute; top: 8px; left: 8px;
  background: var(--green-main); color: #fff;
  font-size: .72rem; padding: 2px 8px; border-radius: 4px; font-weight: 700;
}
.video-info { padding: 14px 16px; }
.video-title {
  font-size: .95rem; font-weight: 700; color: var(--text-dark);
  margin-bottom: 6px; line-height: 1.4;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}
.video-meta { display: flex; gap: 14px; font-size: .8rem; color: var(--text-light); }
.video-meta span { display: flex; align-items: center; gap: 4px; }

/* =============================================
   模块卡片
   ============================================= */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
}
.module-card {
  background: #fff; border-radius: var(--radius);
  padding: 28px 22px; text-align: center;
  box-shadow: var(--shadow);
  transition: transform .25s, box-shadow .25s;
  border-top: 4px solid var(--green-light);
}
.module-card:hover { transform: translateY(-5px); box-shadow: 0 10px 30px rgba(30,80,30,.16); }
.module-icon { font-size: 2.4rem; margin-bottom: 14px; }
.module-card h3 { font-size: 1.05rem; font-weight: 800; color: var(--green-dark); margin-bottom: 8px; }
.module-card p { font-size: .88rem; color: var(--text-light); line-height: 1.6; }

/* =============================================
   专家展示
   ============================================= */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 28px;
}
.expert-card {
  background: #fff; border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow);
  transition: transform .25s;
}
.expert-card:hover { transform: translateY(-5px); }
.expert-img { width: 100%; aspect-ratio: 3/4; object-fit: cover; }
.expert-body { padding: 18px 20px; }
.expert-name { font-size: 1.1rem; font-weight: 800; color: var(--green-dark); margin-bottom: 4px; }
.expert-role { font-size: .82rem; color: var(--green-mid); font-weight: 600; margin-bottom: 10px; }
.expert-desc { font-size: .85rem; color: var(--text-light); line-height: 1.6; margin-bottom: 14px; }
.expert-awards { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 14px; }
.award-tag {
  background: var(--green-pale); color: var(--green-dark);
  font-size: .75rem; padding: 3px 10px; border-radius: 12px; font-weight: 600;
}
.expert-btns { display: flex; gap: 10px; }
.btn-sm {
  flex: 1; text-align: center;
  padding: 8px 12px; border-radius: 8px;
  font-size: .82rem; font-weight: 700;
  transition: background .2s;
}
.btn-sm-green { background: var(--green-main); color: #fff; }
.btn-sm-green:hover { background: var(--green-dark); color: #fff; }
.btn-sm-outline { border: 2px solid var(--green-main); color: var(--green-main); }
.btn-sm-outline:hover { background: var(--green-pale); }

/* =============================================
   FAQ
   ============================================= */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: #fff; border-radius: var(--radius);
  margin-bottom: 14px; box-shadow: var(--shadow);
  overflow: hidden;
}
.faq-q {
  padding: 18px 22px; cursor: pointer;
  display: flex; justify-content: space-between; align-items: center;
  font-weight: 700; color: var(--green-dark); font-size: .98rem;
  transition: background .2s;
}
.faq-q:hover { background: var(--green-pale); }
.faq-q .arrow { transition: transform .3s; font-size: 1.1rem; }
.faq-item.open .faq-q .arrow { transform: rotate(180deg); }
.faq-a {
  max-height: 0; overflow: hidden;
  transition: max-height .35s ease, padding .35s;
  padding: 0 22px; font-size: .9rem; color: var(--text-mid); line-height: 1.7;
}
.faq-item.open .faq-a { max-height: 300px; padding: 0 22px 18px; }

/* =============================================
   用户评价
   ============================================= */
.review-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 22px;
}
.review-card {
  background: #fff; border-radius: var(--radius);
  padding: 22px; box-shadow: var(--shadow);
  border-left: 4px solid var(--green-light);
}
.review-stars { color: var(--gold); font-size: 1rem; margin-bottom: 10px; }
.review-text { font-size: .9rem; color: var(--text-mid); line-height: 1.7; margin-bottom: 14px; }
.review-user { display: flex; align-items: center; gap: 10px; }
.review-avatar {
  width: 40px; height: 40px; border-radius: 50%;
  background: var(--green-pale); display: flex; align-items: center; justify-content: center;
  font-size: 1.1rem; font-weight: 800; color: var(--green-dark);
}
.review-name { font-weight: 700; font-size: .88rem; color: var(--text-dark); }
.review-date { font-size: .78rem; color: var(--text-light); }

/* =============================================
   合作品牌 Logo 墙
   ============================================= */
.brand-wall {
  display: flex; flex-wrap: wrap; gap: 20px;
  justify-content: center; align-items: center;
}
.brand-logo {
  background: #fff; border-radius: 10px;
  padding: 14px 24px; box-shadow: var(--shadow);
  font-size: .9rem; font-weight: 700; color: var(--text-mid);
  transition: transform .2s, box-shadow .2s;
  min-width: 120px; text-align: center;
}
.brand-logo:hover { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(30,80,30,.15); color: var(--green-dark); }

/* =============================================
   联系 & 社交
   ============================================= */
.contact-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 40px;
}
.contact-info h3 { font-size: 1.2rem; font-weight: 800; color: var(--green-dark); margin-bottom: 18px; }
.contact-item { display: flex; gap: 12px; margin-bottom: 14px; align-items: flex-start; }
.contact-icon { font-size: 1.3rem; margin-top: 2px; }
.contact-text strong { display: block; font-size: .88rem; color: var(--text-dark); }
.contact-text span { font-size: .85rem; color: var(--text-light); }

.qr-group { display: flex; gap: 24px; flex-wrap: wrap; }
.qr-item { text-align: center; }
.qr-code {
  width: 110px; height: 110px; border-radius: 10px;
  background: var(--green-pale); display: flex; align-items: center; justify-content: center;
  font-size: 2.5rem; margin-bottom: 8px; border: 2px solid var(--green-light);
}
.qr-label { font-size: .8rem; color: var(--text-mid); font-weight: 600; }

.social-share { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 24px; }
.share-btn {
  display: flex; align-items: center; gap: 7px;
  padding: 9px 18px; border-radius: 22px;
  font-size: .85rem; font-weight: 700; cursor: pointer;
  border: none; transition: transform .15s, opacity .2s;
}
.share-btn:hover { transform: translateY(-2px); opacity: .9; }
.share-wechat { background: #07c160; color: #fff; }
.share-weibo  { background: #e6162d; color: #fff; }
.share-douyin { background: #010101; color: #fff; }
.share-bilibili { background: #00a1d6; color: #fff; }

/* =============================================
   页脚
   ============================================= */
.site-footer {
  background: var(--green-dark); color: rgba(255,255,255,.85);
  padding: 50px 0 24px;
}
.footer-grid {
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px;
  margin-bottom: 40px;
}
.footer-brand .logo-text { color: #fff; font-size: 1.4rem; margin-bottom: 12px; }
.footer-brand p { font-size: .85rem; line-height: 1.7; color: rgba(255,255,255,.7); }
.footer-col h4 { font-size: .95rem; font-weight: 800; color: #fff; margin-bottom: 14px; }
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul li a { font-size: .85rem; color: rgba(255,255,255,.7); transition: color .2s; }
.footer-col ul li a:hover { color: var(--gold); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.15);
  padding-top: 20px; text-align: center;
  font-size: .82rem; color: rgba(255,255,255,.55);
}
.footer-bottom a { color: rgba(255,255,255,.7); }
.footer-bottom a:hover { color: var(--gold); }

/* =============================================
   面包屑
   ============================================= */
.breadcrumb {
  background: var(--green-pale); padding: 10px 0;
  font-size: .85rem; color: var(--text-light);
}
.breadcrumb a { color: var(--green-mid); }
.breadcrumb span { margin: 0 6px; }

/* =============================================
   内页 Hero
   ============================================= */
.page-hero {
  background: linear-gradient(135deg, var(--green-dark) 0%, var(--green-mid) 100%);
  padding: 60px 0; text-align: center; color: #fff;
}
.page-hero h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 900; margin-bottom: 12px; }
.page-hero p { font-size: 1rem; color: rgba(255,255,255,.85); max-width: 600px; margin: 0 auto; }

/* =============================================
   AI 赋能模块
   ============================================= */
.ai-feature {
  display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center;
}
.ai-feature.reverse { direction: rtl; }
.ai-feature.reverse > * { direction: ltr; }
.ai-img { border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.ai-img img { width: 100%; height: 320px; object-fit: cover; }
.ai-text h3 { font-size: 1.5rem; font-weight: 800; color: var(--green-dark); margin-bottom: 14px; }
.ai-text p { color: var(--text-mid); line-height: 1.8; margin-bottom: 18px; }
.ai-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.ai-tag {
  background: var(--green-pale); color: var(--green-dark);
  padding: 5px 14px; border-radius: 16px; font-size: .82rem; font-weight: 600;
}

/* =============================================
   How-To 步骤
   ============================================= */
.steps-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 24px;
}
.step-card {
  background: #fff; border-radius: var(--radius); padding: 28px 20px; text-align: center;
  box-shadow: var(--shadow); position: relative;
}
.step-num {
  width: 48px; height: 48px; border-radius: 50%;
  background: var(--green-main); color: #fff;
  font-size: 1.3rem; font-weight: 900;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 16px;
}
.step-card h4 { font-size: .98rem; font-weight: 800; color: var(--green-dark); margin-bottom: 8px; }
.step-card p { font-size: .85rem; color: var(--text-light); line-height: 1.6; }

/* =============================================
   响应式
   ============================================= */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .ai-feature { grid-template-columns: 1fr; }
  .ai-feature.reverse { direction: ltr; }
}
@media (max-width: 768px) {
  .main-nav { display: none; }
  .hero { min-height: 420px; }
  .hero-stats { gap: 18px; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
  .video-grid { grid-template-columns: 1fr 1fr; }
  .search-input { width: 260px; }
}
@media (max-width: 480px) {
  .video-grid { grid-template-columns: 1fr; }
  .module-grid { grid-template-columns: 1fr 1fr; }
  .hero h1 { font-size: 1.7rem; }
}

/* =============================================
   干扰标签隐藏（不破坏布局）
   ============================================= */
.noise-wrap { display: none !important; }