/* ============================================================
   91 修车改装视频社区 - 主样式文件
   域名: sh6vc4.cn
   配色: 工业橙 #FF6B1A + 深钢蓝 #0D1B2A + 银灰 #C8D0D8
   ============================================================ */

/* ---- CSS变量 ---- */
:root {
  --brand-orange: #FF6B1A;
  --brand-orange-dark: #E05500;
  --brand-orange-light: #FF8C47;
  --steel-blue: #0D1B2A;
  --steel-blue-mid: #1A2F45;
  --steel-blue-light: #243D57;
  --silver: #C8D0D8;
  --silver-light: #E8ECF0;
  --white: #FFFFFF;
  --text-dark: #1A1A2E;
  --text-mid: #3D4A5C;
  --text-light: #6B7A8D;
  --accent-yellow: #FFD700;
  --accent-red: #E63946;
  --success: #2DC653;
  --border: rgba(200,208,216,0.2);
  --shadow-sm: 0 2px 8px rgba(13,27,42,0.15);
  --shadow-md: 0 6px 24px rgba(13,27,42,0.2);
  --shadow-lg: 0 12px 48px rgba(13,27,42,0.3);
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
  --font-main: 'PingFang SC','Microsoft YaHei','Helvetica Neue',Arial,sans-serif;
  --font-mono: 'SF Mono','Fira Code',monospace;
}

/* ---- 重置 ---- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-main);
  background: var(--steel-blue);
  color: var(--silver-light);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--brand-orange); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--brand-orange-light); }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font-family: var(--font-main); }

/* ---- 干扰标签隐藏 ---- */
.qx-noise, .noise-wrap { display: none !important; visibility: hidden !important; }

/* ============================================================
   顶部通知栏
   ============================================================ */
.top-bar {
  background: var(--brand-orange);
  color: var(--white);
  text-align: center;
  padding: 6px 20px;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.5px;
}
.top-bar a { color: var(--white); text-decoration: underline; }

/* ============================================================
   导航栏
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(13,27,42,0.97);
  backdrop-filter: blur(12px);
  border-bottom: 2px solid var(--brand-orange);
  box-shadow: var(--shadow-md);
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 20px;
}
.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}
.logo-icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--brand-orange), var(--brand-orange-dark));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  font-weight: 900;
  color: var(--white);
  letter-spacing: -1px;
  box-shadow: 0 0 16px rgba(255,107,26,0.4);
}
.logo-text { display: flex; flex-direction: column; }
.logo-name {
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--white);
  line-height: 1.1;
  letter-spacing: 1px;
}
.logo-slogan {
  font-size: 0.65rem;
  color: var(--brand-orange-light);
  letter-spacing: 2px;
  text-transform: uppercase;
}
.main-nav { display: flex; align-items: center; gap: 4px; }
.main-nav a {
  color: var(--silver);
  font-size: 0.88rem;
  font-weight: 600;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  white-space: nowrap;
  position: relative;
}
.main-nav a::after {
  content: '';
  position: absolute;
  bottom: 4px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background: var(--brand-orange);
  transition: var(--transition);
}
.main-nav a:hover { color: var(--white); background: var(--steel-blue-light); }
.main-nav a:hover::after { width: 60%; }
.main-nav a.active { color: var(--brand-orange); }
.main-nav a.active::after { width: 60%; }
.header-cta {
  background: var(--brand-orange);
  color: var(--white) !important;
  padding: 8px 18px !important;
  border-radius: var(--radius-md) !important;
  font-weight: 700 !important;
}
.header-cta:hover { background: var(--brand-orange-dark) !important; color: var(--white) !important; }
.header-cta::after { display: none !important; }
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--silver);
  border-radius: 2px;
  transition: var(--transition);
}

/* ---- 搜索框 ---- */
.search-bar-wrap {
  background: var(--steel-blue-mid);
  border-bottom: 1px solid var(--border);
  padding: 12px 24px;
}
.search-bar-inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
}
.search-form {
  flex: 1;
  display: flex;
  align-items: center;
  background: var(--steel-blue-light);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: var(--transition);
}
.search-form:focus-within {
  border-color: var(--brand-orange);
  box-shadow: 0 0 0 3px rgba(255,107,26,0.15);
}
.search-icon {
  padding: 0 14px;
  color: var(--text-light);
  font-size: 1rem;
}
.search-input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  color: var(--white);
  font-size: 0.9rem;
  padding: 10px 0;
  font-family: var(--font-main);
}
.search-input::placeholder { color: var(--text-light); }
.search-btn {
  background: var(--brand-orange);
  color: var(--white);
  border: none;
  padding: 10px 20px;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  transition: var(--transition);
}
.search-btn:hover { background: var(--brand-orange-dark); }
.search-tags { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.search-tag-label { font-size: 0.78rem; color: var(--text-light); white-space: nowrap; }
.search-tag {
  font-size: 0.75rem;
  color: var(--silver);
  background: var(--steel-blue-light);
  border: 1px solid var(--border);
  padding: 3px 10px;
  border-radius: 20px;
  cursor: pointer;
  transition: var(--transition);
}
.search-tag:hover { color: var(--brand-orange); border-color: var(--brand-orange); }

/* ============================================================
   Hero Banner
   ============================================================ */
.hero-section {
  position: relative;
  min-height: 580px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--steel-blue);
}
.hero-bg-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
  opacity: 0.45;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(13,27,42,0.92) 0%,
    rgba(13,27,42,0.7) 50%,
    rgba(255,107,26,0.15) 100%
  );
  z-index: 1;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 1280px;
  margin: 0 auto;
  padding: 80px 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
  width: 100%;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255,107,26,0.15);
  border: 1px solid rgba(255,107,26,0.4);
  color: var(--brand-orange-light);
  font-size: 0.78rem;
  font-weight: 700;
  padding: 5px 14px;
  border-radius: 20px;
  margin-bottom: 16px;
  letter-spacing: 1px;
  text-transform: uppercase;
}
.hero-badge::before { content: '●'; font-size: 0.5rem; animation: blink 1.5s infinite; }
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.3} }
.hero-title {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1.15;
  color: var(--white);
  margin-bottom: 8px;
}
.hero-title .brand-highlight {
  color: var(--brand-orange);
  text-shadow: 0 0 30px rgba(255,107,26,0.5);
}
.hero-subtitle {
  font-size: 1.1rem;
  color: var(--silver);
  margin-bottom: 24px;
  font-weight: 500;
}
.hero-desc {
  font-size: 0.92rem;
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 32px;
  max-width: 480px;
}
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, var(--brand-orange), var(--brand-orange-dark));
  color: var(--white);
  font-size: 0.95rem;
  font-weight: 700;
  padding: 13px 28px;
  border-radius: var(--radius-md);
  transition: var(--transition);
  box-shadow: 0 4px 20px rgba(255,107,26,0.35);
  border: none;
  cursor: pointer;
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(255,107,26,0.5);
  color: var(--white);
}
.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: var(--silver);
  font-size: 0.95rem;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--border);
  transition: var(--transition);
  cursor: pointer;
}
.btn-secondary:hover {
  border-color: var(--brand-orange);
  color: var(--brand-orange);
  background: rgba(255,107,26,0.08);
}
.hero-stats {
  display: flex;
  gap: 28px;
  margin-top: 36px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}
.hero-stat-item { text-align: center; }
.hero-stat-num {
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--brand-orange);
  line-height: 1;
}
.hero-stat-label { font-size: 0.72rem; color: var(--text-light); margin-top: 4px; letter-spacing: 0.5px; }
.hero-visual { position: relative; }
.hero-video-preview {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border: 2px solid rgba(255,107,26,0.3);
}
.hero-video-preview img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
}
.hero-play-btn {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%,-50%);
  width: 64px;
  height: 64px;
  background: rgba(255,107,26,0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 0 0 8px rgba(255,107,26,0.2);
}
.hero-play-btn:hover {
  background: var(--brand-orange);
  transform: translate(-50%,-50%) scale(1.1);
  box-shadow: 0 0 0 12px rgba(255,107,26,0.25);
}
.hero-play-btn::after {
  content: '';
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 10px 0 10px 20px;
  border-color: transparent transparent transparent var(--white);
  margin-left: 4px;
}
.hero-floating-tags {
  position: absolute;
  bottom: -16px;
  left: 0;
  right: 0;
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
  padding: 0 16px;
}
.hero-tag {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  color: var(--silver);
  font-size: 0.72rem;
  padding: 4px 12px;
  border-radius: 20px;
  font-weight: 600;
}

/* ============================================================
   通用区块样式
   ============================================================ */
.section { padding: 72px 0; }
.section-alt { background: var(--steel-blue-mid); }
.container { max-width: 1280px; margin: 0 auto; padding: 0 24px; }
.section-header { text-align: center; margin-bottom: 48px; }
.section-tag {
  display: inline-block;
  background: rgba(255,107,26,0.12);
  color: var(--brand-orange);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: 20px;
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 12px;
  border: 1px solid rgba(255,107,26,0.25);
}
.section-title {
  font-size: 2rem;
  font-weight: 800;
  color: var(--white);
  margin-bottom: 12px;
  line-height: 1.3;
}
.section-title .brand { color: var(--brand-orange); }
.section-desc {
  font-size: 0.95rem;
  color: var(--text-light);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.8;
}
.section-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--brand-orange);
  font-size: 0.85rem;
  font-weight: 600;
  margin-top: 36px;
  padding: 8px 20px;
  border: 1.5px solid rgba(255,107,26,0.3);
  border-radius: var(--radius-md);
  transition: var(--transition);
}
.section-more:hover {
  background: rgba(255,107,26,0.1);
  border-color: var(--brand-orange);
}
.text-center { text-align: center; }

/* ============================================================
   统计数字条
   ============================================================ */
.stats-strip {
  background: linear-gradient(90deg, var(--brand-orange-dark), var(--brand-orange), var(--brand-orange-dark));
  padding: 20px 0;
}
.stats-strip-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  gap: 16px;
}
.strip-stat { text-align: center; color: var(--white); }
.strip-stat-num { font-size: 1.6rem; font-weight: 900; line-height: 1; }
.strip-stat-label { font-size: 0.72rem; opacity: 0.85; margin-top: 3px; letter-spacing: 0.5px; }

/* ============================================================
   视频卡片
   ============================================================ */
.video-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.video-card {
  background: var(--steel-blue-mid);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border);
  transition: var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(255,107,26,0.4);
}
.video-thumb {
  position: relative;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: var(--steel-blue-light);
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.06); }
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0,0,0,0.8);
  color: var(--white);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 3px;
  font-family: var(--font-mono);
}
.video-badge {
  position: absolute;
  top: 8px;
  left: 8px;
  font-size: 0.68rem;
  font-weight: 800;
  padding: 3px 8px;
  border-radius: 3px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.badge-hot { background: var(--accent-red); color: var(--white); }
.badge-new { background: var(--brand-orange); color: var(--white); }
.badge-top { background: var(--accent-yellow); color: var(--text-dark); }
.badge-rec { background: var(--success); color: var(--white); }
.badge-edu { background: #7B2FBE; color: var(--white); }
.play-overlay {
  position: absolute;
  inset: 0;
  background: rgba(13,27,42,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: var(--transition);
}
.video-card:hover .play-overlay { opacity: 1; }
.play-btn-circle {
  width: 52px;
  height: 52px;
  background: var(--brand-orange);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 0 6px rgba(255,107,26,0.25);
  transition: var(--transition);
}
.play-btn-circle:hover { transform: scale(1.1); }
.play-btn-circle::after {
  content: '';
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 8px 0 8px 16px;
  border-color: transparent transparent transparent var(--white);
  margin-left: 3px;
}
.video-info { padding: 14px; }
.video-title {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--silver-light);
  line-height: 1.4;
  margin-bottom: 8px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.75rem;
  color: var(--text-light);
  margin-bottom: 8px;
}
.video-views { display: flex; align-items: center; gap: 4px; }
.video-likes { display: flex; align-items: center; gap: 4px; color: var(--brand-orange); }
.video-tags { display: flex; gap: 5px; flex-wrap: wrap; }
.video-tag {
  font-size: 0.68rem;
  background: rgba(255,107,26,0.1);
  color: var(--brand-orange-light);
  padding: 2px 8px;
  border-radius: 3px;
  border: 1px solid rgba(255,107,26,0.2);
}

/* ---- 视频Tab切换 ---- */
.video-tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 28px;
  border-bottom: 2px solid var(--border);
  padding-bottom: 0;
  flex-wrap: wrap;
}
.video-tab {
  padding: 10px 20px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-light);
  cursor: pointer;
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  transition: var(--transition);
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
}
.video-tab:hover { color: var(--silver); background: var(--steel-blue-light); }
.video-tab.active { color: var(--brand-orange); border-bottom-color: var(--brand-orange); background: rgba(255,107,26,0.06); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* ============================================================
   功能模块卡片
   ============================================================ */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.feature-card {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--brand-orange), var(--brand-orange-light));
  transform: scaleX(0);
  transition: var(--transition);
}
.feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: rgba(255,107,26,0.3); }
.feature-card:hover::before { transform: scaleX(1); }
.feature-icon {
  width: 52px;
  height: 52px;
  background: rgba(255,107,26,0.12);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 16px;
  border: 1px solid rgba(255,107,26,0.2);
}
.feature-title { font-size: 1rem; font-weight: 700; color: var(--white); margin-bottom: 8px; }
.feature-desc { font-size: 0.85rem; color: var(--text-light); line-height: 1.7; }
.feature-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: var(--brand-orange);
  font-size: 0.82rem;
  font-weight: 600;
  margin-top: 14px;
}
.feature-link:hover { gap: 8px; }

/* ============================================================
   专家卡片
   ============================================================ */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.expert-card {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition);
  text-align: center;
}
.expert-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: rgba(255,107,26,0.3); }
.expert-avatar {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
  max-height: 180px;
}
.expert-info { padding: 16px; }
.expert-name { font-size: 0.95rem; font-weight: 700; color: var(--white); margin-bottom: 4px; }
.expert-role { font-size: 0.75rem; color: var(--brand-orange); font-weight: 600; margin-bottom: 8px; }
.expert-desc { font-size: 0.78rem; color: var(--text-light); line-height: 1.6; margin-bottom: 12px; }
.expert-actions { display: flex; gap: 6px; justify-content: center; }
.expert-btn {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 5px 12px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}
.expert-btn-primary {
  background: var(--brand-orange);
  color: var(--white);
}
.expert-btn-primary:hover { background: var(--brand-orange-dark); color: var(--white); }
.expert-btn-secondary {
  border: 1px solid var(--border);
  color: var(--silver);
}
.expert-btn-secondary:hover { border-color: var(--brand-orange); color: var(--brand-orange); }

/* ============================================================
   AI赋能区块
   ============================================================ */
.ai-section {
  background: linear-gradient(135deg, var(--steel-blue) 0%, var(--steel-blue-mid) 100%);
  position: relative;
  overflow: hidden;
}
.ai-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(255,107,26,0.08) 0%, transparent 70%);
  pointer-events: none;
}
.ai-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}
.ai-features { display: flex; flex-direction: column; gap: 20px; }
.ai-feature-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background: rgba(255,107,26,0.05);
  border: 1px solid rgba(255,107,26,0.15);
  border-radius: var(--radius-md);
  transition: var(--transition);
}
.ai-feature-item:hover { background: rgba(255,107,26,0.1); border-color: rgba(255,107,26,0.3); }
.ai-feature-icon {
  width: 44px;
  height: 44px;
  background: rgba(255,107,26,0.15);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  flex-shrink: 0;
}
.ai-feature-text h4 { font-size: 0.95rem; font-weight: 700; color: var(--white); margin-bottom: 4px; }
.ai-feature-text p { font-size: 0.82rem; color: var(--text-light); line-height: 1.6; }
.ai-visual {
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 2px solid rgba(255,107,26,0.25);
  box-shadow: var(--shadow-lg);
}
.ai-visual img { width: 100%; display: block; }
.ai-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  background: var(--brand-orange);
  color: var(--white);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 5px 12px;
  border-radius: 20px;
  letter-spacing: 1px;
}

/* ============================================================
   合作品牌墙
   ============================================================ */
.partners-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
  align-items: center;
}
.partner-item {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: center;
  transition: var(--transition);
}
.partner-item:hover { border-color: rgba(255,107,26,0.4); background: rgba(255,107,26,0.05); }
.partner-name { font-size: 0.82rem; font-weight: 700; color: var(--silver); }
.partner-type { font-size: 0.68rem; color: var(--text-light); margin-top: 3px; }

/* ============================================================
   FAQ
   ============================================================ */
.faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
}
.faq-item.open { border-color: rgba(255,107,26,0.4); }
.faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 22px;
  cursor: pointer;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--silver-light);
  transition: var(--transition);
  gap: 12px;
}
.faq-question:hover { color: var(--white); }
.faq-item.open .faq-question { color: var(--brand-orange); }
.faq-icon {
  width: 24px;
  height: 24px;
  background: rgba(255,107,26,0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 1rem;
  color: var(--brand-orange);
  transition: var(--transition);
}
.faq-item.open .faq-icon { transform: rotate(45deg); background: var(--brand-orange); color: var(--white); }
.faq-answer {
  display: none;
  padding: 0 22px 18px;
  font-size: 0.88rem;
  color: var(--text-light);
  line-height: 1.8;
  border-top: 1px solid var(--border);
  padding-top: 14px;
}
.faq-item.open .faq-answer { display: block; }

/* ============================================================
   用户评论
   ============================================================ */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.review-card {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 22px;
  transition: var(--transition);
  position: relative;
}
.review-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.review-card::before {
  content: '"';
  position: absolute;
  top: 12px;
  right: 18px;
  font-size: 3rem;
  color: rgba(255,107,26,0.15);
  font-family: Georgia, serif;
  line-height: 1;
}
.review-stars { color: var(--accent-yellow); font-size: 0.85rem; margin-bottom: 10px; letter-spacing: 2px; }
.review-text { font-size: 0.85rem; color: var(--silver); line-height: 1.7; margin-bottom: 16px; }
.review-author { display: flex; align-items: center; gap: 10px; }
.review-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand-orange), var(--brand-orange-dark));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--white);
  flex-shrink: 0;
}
.review-name { font-size: 0.82rem; font-weight: 700; color: var(--white); }
.review-role { font-size: 0.7rem; color: var(--text-light); }

/* ============================================================
   联系/社交区块
   ============================================================ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 24px;
}
.contact-card {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
}
.contact-card h3 { font-size: 1rem; font-weight: 700; color: var(--white); margin-bottom: 16px; }
.contact-item { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; font-size: 0.85rem; color: var(--silver); }
.contact-icon { font-size: 1rem; width: 20px; text-align: center; }
.social-btns { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; }
.social-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}
.social-btn-wechat { background: #07C160; color: var(--white); }
.social-btn-weibo { background: #E6162D; color: var(--white); }
.social-btn-douyin { background: #010101; color: var(--white); border: 1px solid #333; }
.social-btn-bili { background: #00A1D6; color: var(--white); }
.social-btn:hover { opacity: 0.85; transform: translateY(-1px); }
.qr-grid { display: flex; gap: 16px; }
.qr-item { text-align: center; }
.qr-placeholder {
  width: 80px;
  height: 80px;
  background: var(--steel-blue-light);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.6rem;
  color: var(--text-light);
  text-align: center;
  line-height: 1.4;
  margin-bottom: 5px;
}
.qr-label { font-size: 0.68rem; color: var(--text-light); }

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  background: #080F18;
  border-top: 2px solid rgba(255,107,26,0.3);
  padding: 56px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border);
}
.footer-brand-desc { font-size: 0.85rem; color: var(--text-light); line-height: 1.8; margin: 14px 0; }
.footer-col h4 { font-size: 0.88rem; font-weight: 700; color: var(--white); margin-bottom: 16px; padding-bottom: 8px; border-bottom: 1px solid rgba(255,107,26,0.2); }
.footer-links { display: flex; flex-direction: column; gap: 8px; }
.footer-links a { font-size: 0.82rem; color: var(--text-light); transition: var(--transition); }
.footer-links a:hover { color: var(--brand-orange); padding-left: 4px; }
.footer-bottom {
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 0.78rem;
  color: var(--text-light);
}
.footer-bottom-links { display: flex; gap: 16px; }
.footer-bottom-links a { color: var(--text-light); }
.footer-bottom-links a:hover { color: var(--brand-orange); }
.update-time { color: var(--brand-orange-light); font-size: 0.75rem; }

/* ============================================================
   面包屑
   ============================================================ */
.breadcrumb {
  background: var(--steel-blue-mid);
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}
.breadcrumb-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--text-light);
}
.breadcrumb-inner a { color: var(--text-light); }
.breadcrumb-inner a:hover { color: var(--brand-orange); }
.breadcrumb-sep { color: var(--border); }
.breadcrumb-current { color: var(--brand-orange); font-weight: 600; }

/* ============================================================
   内页Hero
   ============================================================ */
.page-hero {
  background: linear-gradient(135deg, var(--steel-blue) 0%, var(--steel-blue-mid) 100%);
  padding: 48px 0;
  border-bottom: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}
.page-hero::after {
  content: '';
  position: absolute;
  right: -100px;
  top: -100px;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255,107,26,0.06) 0%, transparent 70%);
  pointer-events: none;
}
.page-hero-title { font-size: 2rem; font-weight: 800; color: var(--white); margin-bottom: 8px; }
.page-hero-title .brand { color: var(--brand-orange); }
.page-hero-desc { font-size: 0.92rem; color: var(--text-light); max-width: 560px; line-height: 1.8; }

/* ============================================================
   视频模态框
   ============================================================ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.85);
  z-index: 9999;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.modal-overlay.open { display: flex; }
.modal-box {
  background: var(--steel-blue-mid);
  border-radius: var(--radius-lg);
  overflow: hidden;
  max-width: 800px;
  width: 100%;
  border: 1px solid rgba(255,107,26,0.3);
  box-shadow: var(--shadow-lg);
}
.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}
.modal-title { font-size: 0.95rem; font-weight: 700; color: var(--white); }
.modal-close {
  width: 30px;
  height: 30px;
  background: rgba(255,107,26,0.1);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--silver);
  font-size: 1.1rem;
  cursor: pointer;
  transition: var(--transition);
}
.modal-close:hover { background: var(--brand-orange); color: var(--white); }
.modal-video {
  aspect-ratio: 16/9;
  background: #000;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  font-size: 0.9rem;
}

/* ============================================================
   加入社区 How-To
   ============================================================ */
.howto-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  counter-reset: step;
}
.howto-step {
  background: var(--steel-blue-mid);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  text-align: center;
  position: relative;
  transition: var(--transition);
}
.howto-step:hover { border-color: rgba(255,107,26,0.4); transform: translateY(-3px); }
.howto-num {
  width: 40px;
  height: 40px;
  background: var(--brand-orange);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 900;
  color: var(--white);
  margin: 0 auto 14px;
}
.howto-title { font-size: 0.92rem; font-weight: 700; color: var(--white); margin-bottom: 8px; }
.howto-desc { font-size: 0.8rem; color: var(--text-light); line-height: 1.6; }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1024px) {
  .video-grid { grid-template-columns: repeat(3, 1fr); }
  .expert-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .reviews-grid { grid-template-columns: repeat(2, 1fr); }
  .partners-grid { grid-template-columns: repeat(4, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero-content { grid-template-columns: 1fr; }
  .hero-visual { display: none; }
  .ai-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .howto-steps { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .video-grid { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: 1fr; }
  .main-nav { display: none; }
  .main-nav.open { display: flex; flex-direction: column; position: absolute; top: 68px; left: 0; right: 0; background: var(--steel-blue); padding: 16px; border-bottom: 1px solid var(--border); z-index: 999; }
  .nav-toggle { display: flex; }
  .hero-title { font-size: 2rem; }
  .section-title { font-size: 1.5rem; }
  .partners-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .search-tags { display: none; }
}
@media (max-width: 480px) {
  .video-grid { grid-template-columns: 1fr; }
  .reviews-grid { grid-template-columns: 1fr; }
  .expert-grid { grid-template-columns: 1fr; }
  .howto-steps { grid-template-columns: 1fr; }
  .hero-stats { gap: 16px; }
  .hero-stat-num { font-size: 1.4rem; }
}

/* ============================================================
   滚动条
   ============================================================ */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--steel-blue); }
::-webkit-scrollbar-thumb { background: var(--steel-blue-light); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--brand-orange); }

/* ============================================================
   工具类
   ============================================================ */
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-16 { margin-bottom: 16px; }
.hidden { display: none; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0,0,0,0); }