/* ============================================================
   51动漫 - 汽车改装视频社区 | c4z650.cn
   主题: 赛博朋克霓虹绿 | 原创设计
   ============================================================ */

/* === 基础重置 === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  font-family: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
  background: #080c10;
  color: #d0d8e4;
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: #00ff88; text-decoration: none; transition: color .25s; }
a:hover { color: #66ffbb; }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }

/* === CSS变量 === */
:root {
  --neon: #00ff88;
  --neon-dim: #00cc6a;
  --neon-glow: 0 0 12px rgba(0,255,136,.55);
  --accent: #00d4ff;
  --accent-glow: 0 0 12px rgba(0,212,255,.45);
  --dark: #080c10;
  --dark2: #0d1117;
  --dark3: #111820;
  --dark4: #161e28;
  --border: rgba(0,255,136,.18);
  --text: #d0d8e4;
  --text-muted: #7a8a9a;
  --radius: 8px;
  --radius-lg: 16px;
  --transition: .28s cubic-bezier(.4,0,.2,1);
}

/* === 滚动条 === */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--dark2); }
::-webkit-scrollbar-thumb { background: var(--neon-dim); border-radius: 3px; }

/* === 布局容器 === */
.container { max-width: 1240px; margin: 0 auto; padding: 0 20px; }
.section { padding: 80px 0; }
.section-sm { padding: 50px 0; }

/* === 标题系统 === */
.section-header { text-align: center; margin-bottom: 56px; }
.section-label {
  display: inline-block;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--neon);
  background: rgba(0,255,136,.08);
  border: 1px solid var(--border);
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 14px;
}
.section-title {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 800;
  color: #fff;
  line-height: 1.25;
  margin-bottom: 14px;
}
.section-title span { color: var(--neon); }
.section-desc { color: var(--text-muted); font-size: 1rem; max-width: 560px; margin: 0 auto; }

/* === 顶部公告栏 === */
.top-bar {
  background: linear-gradient(90deg, #00ff88 0%, #00d4ff 100%);
  color: #080c10;
  text-align: center;
  font-size: .8rem;
  font-weight: 700;
  padding: 7px 0;
  letter-spacing: .04em;
}
.top-bar a { color: #080c10; font-weight: 800; text-decoration: underline; }

/* === 导航栏 === */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(8,12,16,.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  padding: 0;
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: 0;
  height: 68px;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}
.nav-logo img { width: 38px; height: 38px; border-radius: 50%; border: 2px solid var(--neon); }
.nav-logo-text {
  font-size: 1.2rem;
  font-weight: 900;
  color: #fff;
  letter-spacing: .02em;
}
.nav-logo-text span { color: var(--neon); }

/* 搜索框 */
.nav-search {
  flex: 1;
  max-width: 340px;
  margin: 0 24px;
  position: relative;
}
.nav-search input {
  width: 100%;
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 8px 42px 8px 18px;
  color: var(--text);
  font-size: .9rem;
  outline: none;
  transition: border-color var(--transition);
}
.nav-search input::placeholder { color: var(--text-muted); }
.nav-search input:focus { border-color: var(--neon); box-shadow: var(--neon-glow); }
.nav-search-btn {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--neon);
  cursor: pointer;
  font-size: 1rem;
  padding: 0;
}

/* 导航菜单 */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}
.nav-menu a {
  color: var(--text-muted);
  font-size: .9rem;
  font-weight: 600;
  padding: 8px 14px;
  border-radius: var(--radius);
  transition: all var(--transition);
  white-space: nowrap;
}
.nav-menu a:hover, .nav-menu a.active {
  color: var(--neon);
  background: rgba(0,255,136,.08);
}
.nav-cta {
  background: var(--neon) !important;
  color: #080c10 !important;
  font-weight: 800 !important;
  padding: 8px 18px !important;
  border-radius: 24px !important;
  margin-left: 8px;
}
.nav-cta:hover { background: #66ffbb !important; box-shadow: var(--neon-glow); }

/* 汉堡菜单 */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  margin-left: auto;
}
.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--neon);
  border-radius: 2px;
  transition: all var(--transition);
}

/* === Hero 区域 === */
.hero {
  position: relative;
  min-height: 88vh;
  display: flex;
  align-items: center;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url('../images/hero_banner.jpg');
  background-size: cover;
  background-position: center;
  filter: brightness(.45);
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(8,12,16,.85) 0%, rgba(0,255,136,.06) 60%, rgba(8,12,16,.7) 100%);
}
.hero-grid-lines {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0,255,136,.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0,255,136,.04) 1px, transparent 1px);
  background-size: 60px 60px;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(0,255,136,.1);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 6px 16px;
  font-size: .8rem;
  color: var(--neon);
  font-weight: 700;
  letter-spacing: .06em;
  margin-bottom: 24px;
}
.hero-badge::before { content: ''; width: 8px; height: 8px; background: var(--neon); border-radius: 50%; animation: pulse 2s infinite; }
@keyframes pulse { 0%,100%{opacity:1;transform:scale(1)} 50%{opacity:.5;transform:scale(1.4)} }
.hero h1 {
  font-size: clamp(2.2rem, 5vw, 4rem);
  font-weight: 900;
  color: #fff;
  line-height: 1.15;
  margin-bottom: 20px;
  text-shadow: 0 2px 20px rgba(0,0,0,.5);
}
.hero h1 .brand { color: var(--neon); text-shadow: var(--neon-glow); }
.hero-sub {
  font-size: 1.1rem;
  color: rgba(208,216,228,.8);
  margin-bottom: 36px;
  max-width: 520px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 28px;
  border-radius: 8px;
  font-size: .95rem;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition);
  border: none;
  text-decoration: none;
}
.btn-primary {
  background: var(--neon);
  color: #080c10;
}
.btn-primary:hover { background: #66ffbb; color: #080c10; box-shadow: var(--neon-glow); transform: translateY(-2px); }
.btn-outline {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,.3);
}
.btn-outline:hover { border-color: var(--neon); color: var(--neon); transform: translateY(-2px); }
.btn-accent {
  background: var(--accent);
  color: #080c10;
}
.btn-accent:hover { background: #66e8ff; color: #080c10; box-shadow: var(--accent-glow); transform: translateY(-2px); }

/* 统计数字 */
.hero-stats {
  position: absolute;
  bottom: 48px;
  left: 0;
  right: 0;
  z-index: 2;
}
.hero-stats-inner {
  display: flex;
  gap: 0;
  background: rgba(13,17,23,.75);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  max-width: 700px;
}
.stat-item {
  flex: 1;
  padding: 20px 24px;
  text-align: center;
  border-right: 1px solid var(--border);
}
.stat-item:last-child { border-right: none; }
.stat-num {
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--neon);
  line-height: 1;
  margin-bottom: 4px;
  text-shadow: var(--neon-glow);
}
.stat-label { font-size: .75rem; color: var(--text-muted); letter-spacing: .04em; }

/* === 跑马灯 === */
.ticker {
  background: var(--dark2);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  overflow: hidden;
  padding: 10px 0;
}
.ticker-inner {
  display: flex;
  gap: 60px;
  animation: ticker-scroll 30s linear infinite;
  white-space: nowrap;
}
.ticker-inner:hover { animation-play-state: paused; }
@keyframes ticker-scroll { from{transform:translateX(0)} to{transform:translateX(-50%)} }
.ticker-item {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: .85rem;
  color: var(--text-muted);
}
.ticker-item .dot { width: 6px; height: 6px; background: var(--neon); border-radius: 50%; }

/* === 视频卡片网格 === */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.video-grid-featured {
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: auto auto;
}
.video-grid-featured .video-card:first-child {
  grid-column: 1 / 3;
  grid-row: 1 / 3;
}

.video-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  cursor: pointer;
}
.video-card:hover {
  transform: translateY(-6px);
  border-color: var(--neon);
  box-shadow: 0 16px 40px rgba(0,255,136,.15);
}
.video-thumb {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16/9;
  background: var(--dark4);
}
.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .4s ease;
}
.video-card:hover .video-thumb img { transform: scale(1.06); }
.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(8,12,16,.5);
  opacity: 0;
  transition: opacity var(--transition);
}
.video-card:hover .video-play-btn { opacity: 1; }
.play-icon {
  width: 56px;
  height: 56px;
  background: var(--neon);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 24px rgba(0,255,136,.6);
  transform: scale(.85);
  transition: transform var(--transition);
}
.video-card:hover .play-icon { transform: scale(1); }
.play-icon::after {
  content: '';
  border-left: 20px solid #080c10;
  border-top: 12px solid transparent;
  border-bottom: 12px solid transparent;
  margin-left: 4px;
}
.video-duration {
  position: absolute;
  bottom: 8px;
  right: 10px;
  background: rgba(8,12,16,.8);
  color: #fff;
  font-size: .75rem;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 4px;
}
.video-tag {
  position: absolute;
  top: 10px;
  left: 10px;
  background: var(--neon);
  color: #080c10;
  font-size: .7rem;
  font-weight: 800;
  padding: 3px 10px;
  border-radius: 4px;
  letter-spacing: .04em;
}
.video-info { padding: 16px; }
.video-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
}
.video-category {
  font-size: .72rem;
  color: var(--neon);
  font-weight: 700;
  background: rgba(0,255,136,.08);
  padding: 2px 8px;
  border-radius: 4px;
}
.video-date { font-size: .72rem; color: var(--text-muted); margin-left: auto; }
.video-title {
  font-size: .95rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 10px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.video-stats {
  display: flex;
  gap: 14px;
  font-size: .78rem;
  color: var(--text-muted);
}
.video-stats span { display: flex; align-items: center; gap: 4px; }

/* === 功能模块卡片 === */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 20px;
}
.module-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 22px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
.module-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--neon), var(--accent));
  opacity: 0;
  transition: opacity var(--transition);
}
.module-card:hover { border-color: var(--neon); transform: translateY(-4px); box-shadow: 0 12px 32px rgba(0,255,136,.12); }
.module-card:hover::before { opacity: 1; }
.module-icon {
  width: 52px; height: 52px;
  background: rgba(0,255,136,.1);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 16px;
}
.module-title { font-size: 1rem; font-weight: 800; color: #fff; margin-bottom: 8px; }
.module-desc { font-size: .85rem; color: var(--text-muted); line-height: 1.6; }
.module-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: .82rem;
  color: var(--neon);
  font-weight: 700;
  margin-top: 14px;
}
.module-link::after { content: '→'; transition: transform var(--transition); }
.module-card:hover .module-link::after { transform: translateX(4px); }

/* === AI赋能区域 === */
.ai-section {
  background: linear-gradient(135deg, var(--dark2) 0%, rgba(0,255,136,.04) 50%, var(--dark2) 100%);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.ai-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.ai-image { position: relative; border-radius: var(--radius-lg); overflow: hidden; }
.ai-image img { width: 100%; border-radius: var(--radius-lg); }
.ai-image::after {
  content: '';
  position: absolute;
  inset: 0;
  border: 2px solid var(--neon);
  border-radius: var(--radius-lg);
  opacity: .3;
  pointer-events: none;
}
.ai-features { display: flex; flex-direction: column; gap: 20px; margin-top: 28px; }
.ai-feature {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 18px;
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: border-color var(--transition);
}
.ai-feature:hover { border-color: var(--neon); }
.ai-feature-icon {
  width: 40px; height: 40px;
  background: rgba(0,255,136,.1);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
}
.ai-feature-title { font-size: .9rem; font-weight: 700; color: #fff; margin-bottom: 4px; }
.ai-feature-desc { font-size: .82rem; color: var(--text-muted); }

/* === 专家展示 === */
.expert-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 24px; }
.expert-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
}
.expert-card:hover { border-color: var(--neon); transform: translateY(-4px); box-shadow: 0 12px 32px rgba(0,255,136,.12); }
.expert-header {
  background: linear-gradient(135deg, var(--dark4), rgba(0,255,136,.06));
  padding: 28px 24px;
  display: flex;
  gap: 18px;
  align-items: center;
}
.expert-avatar {
  width: 72px; height: 72px;
  border-radius: 50%;
  border: 3px solid var(--neon);
  object-fit: cover;
  flex-shrink: 0;
}
.expert-name { font-size: 1.1rem; font-weight: 800; color: #fff; margin-bottom: 4px; }
.expert-role {
  font-size: .78rem;
  color: var(--neon);
  background: rgba(0,255,136,.08);
  padding: 2px 10px;
  border-radius: 12px;
  display: inline-block;
  margin-bottom: 6px;
}
.expert-org { font-size: .8rem; color: var(--text-muted); }
.expert-body { padding: 20px 24px; }
.expert-bio { font-size: .85rem; color: var(--text-muted); margin-bottom: 16px; line-height: 1.7; }
.expert-awards { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.award-tag {
  font-size: .72rem;
  background: rgba(0,212,255,.08);
  border: 1px solid rgba(0,212,255,.2);
  color: var(--accent);
  padding: 3px 10px;
  border-radius: 12px;
}
.expert-actions { display: flex; gap: 10px; }
.expert-btn {
  flex: 1;
  text-align: center;
  padding: 9px;
  border-radius: var(--radius);
  font-size: .82rem;
  font-weight: 700;
  transition: all var(--transition);
}
.expert-btn-primary { background: var(--neon); color: #080c10; }
.expert-btn-primary:hover { background: #66ffbb; color: #080c10; }
.expert-btn-outline { border: 1px solid var(--border); color: var(--text-muted); }
.expert-btn-outline:hover { border-color: var(--neon); color: var(--neon); }

/* === 合作品牌 === */
.partners-section { background: var(--dark2); }
.partners-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  align-items: center;
}
.partner-logo {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 28px;
  font-size: .9rem;
  font-weight: 700;
  color: var(--text-muted);
  transition: all var(--transition);
  white-space: nowrap;
}
.partner-logo:hover { border-color: var(--neon); color: var(--neon); }

/* === 用户评价 === */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}
.review-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: border-color var(--transition);
}
.review-card:hover { border-color: rgba(0,255,136,.35); }
.review-stars { color: #ffd700; font-size: 1rem; margin-bottom: 12px; letter-spacing: 2px; }
.review-text { font-size: .9rem; color: var(--text-muted); line-height: 1.7; margin-bottom: 18px; font-style: italic; }
.review-author { display: flex; align-items: center; gap: 12px; }
.review-avatar {
  width: 40px; height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--neon), var(--accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: .85rem;
  font-weight: 800;
  color: #080c10;
  flex-shrink: 0;
}
.review-name { font-size: .88rem; font-weight: 700; color: #fff; }
.review-meta { font-size: .75rem; color: var(--text-muted); }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
  transition: border-color var(--transition);
}
.faq-item.open { border-color: var(--neon); }
.faq-question {
  padding: 20px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  font-size: .95rem;
  font-weight: 700;
  color: #fff;
  user-select: none;
}
.faq-question:hover { color: var(--neon); }
.faq-arrow {
  width: 24px; height: 24px;
  border: 1px solid var(--border);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: .7rem;
  color: var(--neon);
  transition: transform var(--transition);
  flex-shrink: 0;
}
.faq-item.open .faq-arrow { transform: rotate(180deg); border-color: var(--neon); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height .35s ease, padding .35s ease;
  padding: 0 24px;
  font-size: .88rem;
  color: var(--text-muted);
  line-height: 1.8;
}
.faq-item.open .faq-answer { max-height: 300px; padding: 0 24px 20px; }

/* === 联系区域 === */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; }
.contact-info-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px;
}
.contact-info-title { font-size: 1.1rem; font-weight: 800; color: #fff; margin-bottom: 24px; }
.contact-info-item {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  margin-bottom: 18px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--border);
}
.contact-info-item:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }
.contact-info-icon {
  width: 38px; height: 38px;
  background: rgba(0,255,136,.1);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  flex-shrink: 0;
}
.contact-info-label { font-size: .78rem; color: var(--text-muted); margin-bottom: 3px; }
.contact-info-value { font-size: .9rem; color: #fff; font-weight: 600; }
.qr-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 24px; }
.qr-item { text-align: center; }
.qr-item img { width: 100px; height: 100px; margin: 0 auto 8px; border: 2px solid var(--border); border-radius: var(--radius); }
.qr-label { font-size: .78rem; color: var(--text-muted); }
.social-links { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 20px; }
.social-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: var(--dark4);
  border: 1px solid var(--border);
  border-radius: 24px;
  font-size: .82rem;
  color: var(--text-muted);
  transition: all var(--transition);
}
.social-btn:hover { border-color: var(--neon); color: var(--neon); }

/* === 加入社区 === */
.join-section {
  background: linear-gradient(135deg, rgba(0,255,136,.06) 0%, rgba(0,212,255,.04) 100%);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.join-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-top: 48px; }
.join-step {
  text-align: center;
  position: relative;
}
.join-step:not(:last-child)::after {
  content: '→';
  position: absolute;
  right: -14px;
  top: 20px;
  color: var(--neon);
  font-size: 1.2rem;
}
.step-num {
  width: 48px; height: 48px;
  background: var(--neon);
  color: #080c10;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  font-weight: 900;
  margin: 0 auto 14px;
}
.step-title { font-size: .9rem; font-weight: 700; color: #fff; margin-bottom: 6px; }
.step-desc { font-size: .8rem; color: var(--text-muted); }

/* === 底部 === */
footer {
  background: var(--dark2);
  border-top: 1px solid var(--border);
  padding: 60px 0 0;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}
.footer-brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}
.footer-brand-logo img { width: 36px; height: 36px; border-radius: 50%; border: 2px solid var(--neon); }
.footer-brand-name { font-size: 1.1rem; font-weight: 900; color: #fff; }
.footer-brand-name span { color: var(--neon); }
.footer-desc { font-size: .85rem; color: var(--text-muted); line-height: 1.8; margin-bottom: 20px; }
.footer-col-title { font-size: .85rem; font-weight: 800; color: #fff; margin-bottom: 16px; letter-spacing: .06em; text-transform: uppercase; }
.footer-links { display: flex; flex-direction: column; gap: 10px; }
.footer-links a { font-size: .85rem; color: var(--text-muted); transition: color var(--transition); }
.footer-links a:hover { color: var(--neon); }
.footer-bottom {
  border-top: 1px solid var(--border);
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-copy { font-size: .82rem; color: var(--text-muted); }
.footer-copy a { color: var(--neon); }
.update-time { font-size: .78rem; color: var(--text-muted); }

/* === 面包屑 === */
.breadcrumb {
  padding: 14px 0;
  font-size: .82rem;
  color: var(--text-muted);
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--neon); }
.breadcrumb span { color: var(--neon); margin: 0 6px; }

/* === 内页Hero === */
.page-hero {
  background: linear-gradient(135deg, var(--dark2) 0%, rgba(0,255,136,.04) 100%);
  border-bottom: 1px solid var(--border);
  padding: 56px 0 48px;
}
.page-hero h1 { font-size: clamp(1.8rem, 3.5vw, 2.8rem); font-weight: 900; color: #fff; margin-bottom: 12px; }
.page-hero h1 span { color: var(--neon); }
.page-hero p { font-size: 1rem; color: var(--text-muted); max-width: 560px; }

/* === 标签页 === */
.tabs { display: flex; gap: 4px; margin-bottom: 32px; flex-wrap: wrap; }
.tab-btn {
  padding: 9px 20px;
  border-radius: 24px;
  font-size: .88rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-muted);
}
.tab-btn:hover, .tab-btn.active {
  background: var(--neon);
  color: #080c10;
  border-color: var(--neon);
  font-weight: 800;
}

/* === 工具卡片 === */
.tool-card {
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all var(--transition);
}
.tool-card:hover { border-color: var(--neon); transform: translateY(-3px); }
.tool-header { display: flex; align-items: center; gap: 14px; margin-bottom: 16px; }
.tool-icon {
  width: 48px; height: 48px;
  background: linear-gradient(135deg, rgba(0,255,136,.15), rgba(0,212,255,.1));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
}
.tool-name { font-size: 1rem; font-weight: 800; color: #fff; }
.tool-badge {
  font-size: .68rem;
  background: var(--neon);
  color: #080c10;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 800;
  margin-left: 8px;
}
.tool-desc { font-size: .85rem; color: var(--text-muted); line-height: 1.7; margin-bottom: 18px; }
.tool-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.tool-tag {
  font-size: .72rem;
  background: var(--dark4);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 3px 10px;
  border-radius: 12px;
}

/* === 表单 === */
.form-group { margin-bottom: 20px; }
.form-label { display: block; font-size: .85rem; font-weight: 700; color: var(--text); margin-bottom: 8px; }
.form-control {
  width: 100%;
  background: var(--dark3);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 16px;
  color: var(--text);
  font-size: .9rem;
  outline: none;
  transition: border-color var(--transition);
  font-family: inherit;
}
.form-control:focus { border-color: var(--neon); box-shadow: var(--neon-glow); }
textarea.form-control { resize: vertical; min-height: 120px; }

/* === 通知条 === */
.alert {
  padding: 14px 20px;
  border-radius: var(--radius);
  font-size: .88rem;
  margin-bottom: 20px;
  border-left: 4px solid;
}
.alert-success { background: rgba(0,255,136,.08); border-color: var(--neon); color: var(--neon); }
.alert-info { background: rgba(0,212,255,.08); border-color: var(--accent); color: var(--accent); }

/* === 响应式 === */
@media (max-width: 1024px) {
  .video-grid-featured { grid-template-columns: 1fr 1fr; }
  .video-grid-featured .video-card:first-child { grid-column: 1 / 3; grid-row: auto; }
  .ai-layout { grid-template-columns: 1fr; gap: 36px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .join-steps { grid-template-columns: repeat(2, 1fr); }
  .join-step:nth-child(2)::after { display: none; }
}
@media (max-width: 768px) {
  .section { padding: 56px 0; }
  .nav-search { display: none; }
  .nav-menu { display: none; position: fixed; top: 68px; left: 0; right: 0; background: var(--dark2); border-bottom: 1px solid var(--border); flex-direction: column; padding: 16px; gap: 4px; z-index: 999; }
  .nav-menu.open { display: flex; }
  .nav-menu a { padding: 12px 16px; border-radius: var(--radius); }
  .nav-toggle { display: flex; }
  .hero { min-height: 70vh; }
  .hero-stats { position: static; margin-top: 36px; }
  .hero-stats-inner { flex-wrap: wrap; }
  .stat-item { min-width: 50%; border-right: none; border-bottom: 1px solid var(--border); }
  .stat-item:nth-child(odd) { border-right: 1px solid var(--border); }
  .stat-item:last-child { border-bottom: none; }
  .video-grid-featured { grid-template-columns: 1fr; }
  .video-grid-featured .video-card:first-child { grid-column: auto; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .join-steps { grid-template-columns: 1fr 1fr; }
  .join-step::after { display: none; }
  .module-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
  .hero h1 { font-size: 1.8rem; }
  .hero-actions { flex-direction: column; }
  .btn { width: 100%; justify-content: center; }
  .module-grid { grid-template-columns: 1fr; }
  .join-steps { grid-template-columns: 1fr; }
  .expert-grid { grid-template-columns: 1fr; }
  .reviews-grid { grid-template-columns: 1fr; }
}

/* === 干扰标签容器（display:none） === */
.kkt-hidden-wrap { display: none !important; visibility: hidden !important; }