* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: -apple-system, "Microsoft YaHei", sans-serif; color: #334155; line-height: 1.8; background: #F5F5F5; padding-bottom: 0; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ========== 顶部导航（黑底白字红悬停） ========== */
.site-header { background: #0A0A0A; position: sticky; top: 0; z-index: 1000; box-shadow: 0 2px 15px rgba(0,0,0,0.3); border-top: 4px solid #DC2626; }
.header-top .container { display: flex; align-items: center; justify-content: space-between; height: 80px; }
.logo a { font-size: 28px; font-weight: 800; color: #FFFFFF; letter-spacing: 1px; }
.logo a span { color: #DC2626; }
.main-nav ul { display: flex; gap: 8px; }
.main-nav > ul > li { position: relative; }
.main-nav > ul > li > a { padding: 12px 18px; font-size: 15px; border-radius: 6px; transition: .3s; display: block; color: #FFFFFF; font-weight: 600; }
.main-nav > ul > li > a:hover { color: #FFFFFF; background: #DC2626; }

/* 下拉菜单桥接 */
.main-nav > ul > li.has-sub::after { content: ''; position: absolute; top: 100%; left: 0; width: 100%; height: 15px; background: transparent; pointer-events: none; }

/* 下拉菜单（黑底红条） */
.sub-menu { position: absolute; top: 100%; left: 0; background: #1A1A1A; min-width: 220px; box-shadow: 0 15px 35px rgba(0,0,0,0.5); border-top: 3px solid #DC2626; border-radius: 0 0 10px 10px; padding: 10px 0; z-index: 999; opacity: 0; visibility: hidden; transform: translateY(10px); transition: all 0.3s ease; white-space: nowrap; }
.has-sub:hover .sub-menu { opacity: 1; visibility: visible; transform: translateY(0); }
.sub-menu li a { padding: 12px 24px; display: block; font-size: 14px; color: #D4D4D4; font-weight: 500; }
.sub-menu li a:hover { background: #DC2626; color: #FFFFFF; padding-left: 30px; }

.header-actions { display: flex; gap: 12px; }
.btn { padding: 10px 26px; border-radius: 8px; font-size: 14px; font-weight: 700; transition: .3s; display: inline-block; cursor: pointer; border: none; }
.btn-primary { background: linear-gradient(135deg, #B91C1C, #DC2626); color: #fff; box-shadow: 0 4px 12px rgba(220,38,38,0.4); }
.btn-primary:hover { background: linear-gradient(135deg, #991B1B, #B91C1C); box-shadow: 0 6px 18px rgba(220,38,38,0.6); transform: translateY(-2px); }
.btn-outline { border: 2px solid #FFFFFF; color: #FFFFFF; background: transparent; }
.btn-outline:hover { background: #FFFFFF; color: #0A0A0A; transform: translateY(-2px); }
.header-qq { background: #1A1A1A; padding: 8px 0; text-align: right; font-size: 13px; color: #D4D4D4; font-weight: 500; border-top: 1px solid #2A2A2A; }
.header-qq span { color: #DC2626; font-weight: 700; }
.mobile-toggle { display: none; font-size: 28px; color: #FFFFFF; cursor: pointer; }

/* ========== 底部（黑底红装饰） ========== */
.site-footer { background: #0A0A0A; color: #A3A3A3; padding: 70px 0 0; margin-top: 80px; border-top: 4px solid #DC2626; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; }
.footer-col h4 { color: #FFFFFF; margin-bottom: 20px; font-size: 16px; font-weight: 700; position: relative; padding-bottom: 12px; }
.footer-col h4::after { content: ''; position: absolute; left: 0; bottom: 0; width: 40px; height: 3px; background: #DC2626; border-radius: 2px; }
.footer-col p { font-size: 14px; margin-bottom: 12px; line-height: 1.8; color: #A3A3A3; }
.footer-col li { margin-bottom: 10px; }
.footer-col a { font-size: 14px; color: #A3A3A3; transition: .3s; }
.footer-col a:hover { color: #DC2626; padding-left: 6px; }
.footer-bottom { border-top: 1px solid #2A2A2A; margin-top: 50px; padding: 25px 0; text-align: center; font-size: 13px; color: #737373; }

/* 手机端底部 */
.mobile-bottom-bar { display: none; position: fixed; bottom: 0; left: 0; right: 0; background: #0A0A0A; box-shadow: 0 -4px 15px rgba(0,0,0,.4); z-index: 9999; padding: 10px 16px; gap: 12px; border-top: 2px solid #DC2626; }
.mobile-btn { flex: 1; text-align: center; padding: 14px; border-radius: 10px; font-weight: 700; font-size: 16px; }
.mobile-btn-primary { background: linear-gradient(135deg, #B91C1C, #DC2626); color: #fff; }
.mobile-btn-outline { border: 2px solid #FFFFFF; color: #FFFFFF; }

/* ========== 页面横幅（黑底红球） ========== */
.page-banner { background: linear-gradient(135deg, #000000 0%, #1A1A1A 50%, #0A0A0A 100%); color: #fff; padding: 100px 0; text-align: center; position: relative; overflow: hidden; border-bottom: 3px solid #DC2626; }
.page-banner::before { content: ''; position: absolute; top: -50%; right: -10%; width: 500px; height: 500px; background: radial-gradient(circle, rgba(220,38,38,0.35), transparent 70%); border-radius: 50%; }
.page-banner::after { content: ''; position: absolute; bottom: -60%; left: -10%; width: 400px; height: 400px; background: radial-gradient(circle, rgba(220,38,38,0.15), transparent 70%); border-radius: 50%; }
.page-banner h1 { font-size: 44px; font-weight: 800; margin-bottom: 15px; letter-spacing: 2px; color: #FFFFFF; position: relative; z-index: 1; }
.page-banner h1::after { content: ''; display: block; width: 80px; height: 4px; background: #DC2626; margin: 20px auto 0; border-radius: 2px; }
.page-banner p { font-size: 18px; color: #A3A3A3; max-width: 700px; margin: 20px auto 0; position: relative; z-index: 1; }

/* ========== 首页 Hero 区（黑底红球） ========== */
.hero-section { background: linear-gradient(135deg, #000000 0%, #1A1A1A 60%, #0A0A0A 100%); padding: 130px 0; text-align: center; color: #fff; position: relative; overflow: hidden; }
.hero-section::before { content: ''; position: absolute; top: -30%; left: -10%; width: 600px; height: 600px; background: radial-gradient(circle, rgba(220,38,38,0.4), transparent 70%); border-radius: 50%; }
.hero-section::after { content: ''; position: absolute; bottom: -40%; right: -10%; width: 500px; height: 500px; background: radial-gradient(circle, rgba(220,38,38,0.2), transparent 70%); border-radius: 50%; }
.hero-section h1 { font-size: 54px; font-weight: 800; margin-bottom: 20px; letter-spacing: 2px; color: #fff; position: relative; z-index: 1; }
.hero-section h1 span { color: #DC2626; }
.hero-section p { font-size: 20px; color: #D4D4D4; margin-bottom: 40px; position: relative; z-index: 1; }
.hero-section > .container > div:last-child { position: relative; z-index: 1; }
.hero-section .btn-primary { font-size: 18px; padding: 16px 48px; border-radius: 50px; background: linear-gradient(135deg, #B91C1C, #DC2626); color: #fff; box-shadow: 0 8px 24px rgba(220,38,38,0.5); }
.hero-section .btn-primary:hover { background: linear-gradient(135deg, #991B1B, #B91C1C); transform: translateY(-3px); box-shadow: 0 12px 30px rgba(220,38,38,0.7); }
.hero-section .btn-outline { font-size: 18px; padding: 16px 48px; border-radius: 50px; border: 2px solid #FFFFFF; color: #FFFFFF; background: rgba(255,255,255,0.05); }
.hero-section .btn-outline:hover { background: #FFFFFF; color: #0A0A0A; transform: translateY(-3px); }

/* ========== 数据统计条（黑底红数字） ========== */
.stats-bar { background: #1A1A1A; padding: 50px 0; border-bottom: 3px solid #DC2626; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); text-align: center; }
.stats-grid > div { border-right: 1px dashed #333333; }
.stats-grid > div:last-child { border-right: none; }
.stats-grid .num { font-size: 42px; font-weight: 800; margin-bottom: 8px; color: #DC2626; text-shadow: 0 0 20px rgba(220,38,38,0.4); }
.stats-grid .label { font-size: 14px; color: #D4D4D4; font-weight: 500; letter-spacing: 1px; }

/* ========== 通用内容区 ========== */
.section { padding: 90px 0; }
.section-title { text-align: center; margin-bottom: 60px; }
.section-title h2 { font-size: 38px; font-weight: 800; color: #0A0A0A; margin-bottom: 15px; position: relative; display: inline-block; }
.section-title h2::after { content: ''; position: absolute; left: 50%; bottom: -15px; transform: translateX(-50%); width: 60px; height: 4px; background: #DC2626; border-radius: 2px; }
.section-title p { font-size: 16px; color: #666666; margin-top: 25px; }
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 30px; }

/* ========== 卡片（白底红顶条） ========== */
.card { background: #FFFFFF; border-radius: 16px; padding: 40px 30px; box-shadow: 0 8px 30px rgba(0,0,0,0.08); transition: all 0.4s ease; border: 1px solid #E5E5E5; position: relative; overflow: hidden; }
.card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: #DC2626; transform: scaleX(0); transform-origin: left; transition: transform 0.4s ease; }
.card:hover::before { transform: scaleX(1); }
.card:hover { transform: translateY(-8px); box-shadow: 0 20px 50px rgba(220,38,38,0.2); border-color: #DC2626; }
.card-icon { font-size: 48px; margin-bottom: 24px; display: block; }
.card h3 { font-size: 22px; margin-bottom: 15px; color: #0A0A0A; font-weight: 700; }
.card p { font-size: 15px; color: #666666; line-height: 1.8; }
.card a { color: #DC2626; font-weight: 700; display: inline-block; margin-top: 15px; transition: .3s; }
.card a:hover { color: #0A0A0A; transform: translateX(5px); }

/* ========== 表格（黑头红悬停） ========== */
table { width: 100%; border-collapse: collapse; margin-bottom: 30px; background: #FFFFFF; border-radius: 12px; overflow: hidden; box-shadow: 0 8px 30px rgba(0,0,0,0.1); }
th { background: #0A0A0A; color: #FFFFFF; padding: 20px; text-align: left; font-weight: 600; font-size: 15px; border-bottom: 3px solid #DC2626; }
td { padding: 18px; border-bottom: 1px solid #E5E5E5; color: #334155; font-size: 15px; }
tr:last-child td { border-bottom: none; }
tr:hover td { background: #FEF2F2; color: #0A0A0A; }

/* ========== 文章内容区 ========== */
.article-content { word-wrap: break-word; word-break: break-all; white-space: pre-wrap; line-height: 2.2; font-size: 16px; color: #334155; background: #fff; padding: 50px; border-radius: 16px; box-shadow: 0 8px 30px rgba(0,0,0,0.08); border-top: 4px solid #DC2626; }
.article-content img { max-width: 100%; height: auto; border-radius: 12px; margin: 24px 0; }

/* ========== 响应式 ========== */
@media (max-width: 768px) {
  .main-nav { display: none; position: absolute; top: 80px; left: 0; right: 0; background: #0A0A0A; box-shadow: 0 10px 20px rgba(0,0,0,0.5); border-top: 2px solid #DC2626; }
  .main-nav.active { display: block; }
  .main-nav ul { flex-direction: column; padding: 15px 0; }
  .main-nav > ul > li > a { padding: 15px 25px; color: #FFFFFF; }
  .sub-menu { position: static; box-shadow: none; padding-left: 20px; display: none; opacity: 1; visibility: visible; transform: none; transition: none; background: #1A1A1A; border: none; border-radius: 0; border-top: none; }
  .has-sub > a::after { display: none; }
  .main-nav > ul > li.has-sub::after { display: none; }
  .mobile-toggle { display: block; }
  .header-actions { display: none; }
  .footer-grid { grid-template-columns: 1fr; }
  body { padding-bottom: 80px; }
  .mobile-bottom-bar { display: flex; }
  .hero-section { padding: 80px 0; }
  .hero-section h1 { font-size: 34px; }
  .hero-section p { font-size: 16px; }
  .page-banner { padding: 70px 0; }
  .page-banner h1 { font-size: 30px; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 30px; }
  .stats-grid > div { border-right: none; }
  .stats-grid .num { font-size: 32px; }
  .article-content { padding: 25px; }
  .section-title h2 { font-size: 28px; }
}
@media (max-width: 480px) {
  .stats-grid { grid-template-columns: 1fr; }
}