/* ==========================================================================
   欧易 OKX 官方推广落地页 - 样式表 (SEO & 性能极致优化)
   ========================================================================== */

:root {
  --bg-primary: #0a0d14;
  --bg-secondary: #101522;
  --bg-card: #151b2b;
  --bg-card-hover: #1c2438;
  --border-color: #212c42;
  --border-focus: #3b82f6;
  
  --text-main: #f3f5f8;
  --text-muted: #94a3b8;
  --text-sub: #64748b;
  
  --primary: #00e676;
  --primary-hover: #00c853;
  --primary-glow: rgba(0, 230, 118, 0.25);
  
  --accent-blue: #2979ff;
  --accent-cyan: #00e5ff;
  --accent-gold: #ffab00;
  
  --danger: #ff5252;
  --success: #00e676;
  
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;
  
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-lg: 0 12px 30px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 25px rgba(0, 230, 118, 0.2);
  
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
  --transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-main);
  font-family: var(--font-family);
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
}

/* 顶部阅读进度条 */
.reading-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent-cyan));
  width: 0%;
  z-index: 1001;
  transition: width 0.1s ease;
}

/* 顶部安全与独立推广披露条（核心防社交工程与防飘红项） */
.top-notice-bar {
  background: linear-gradient(90deg, #111726, #162035);
  border-bottom: 1px solid var(--border-color);
  padding: 8px 16px;
  font-size: 0.8125rem;
  color: var(--text-muted);
  text-align: center;
}
.top-notice-bar span {
  color: var(--accent-gold);
  font-weight: 600;
}
.top-notice-bar a {
  color: var(--primary);
  text-decoration: underline;
}

/* 容器通用类 */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* 导航栏 (优化后：高度从72px收紧至64px，通透大气) */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(10, 13, 20, 0.9);
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo-area {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex-shrink: 0;
}

.logo-icon {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.3px;
  line-height: 1.2;
}
.logo-title span {
  color: var(--primary);
  font-weight: 700;
}

.logo-sub {
  font-size: 0.68rem;
  color: var(--text-muted);
  letter-spacing: 0.3px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
  padding: 6px 4px;
  transition: var(--transition);
  position: relative;
}

.nav-link:hover {
  color: #fff;
}

.nav-link:hover::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 4px;
  right: 4px;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

/* 精致邀请码胶囊微组件 (取代原先臃肿的大按钮) */
.code-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: #131b2c;
  border: 1px solid #273752;
  border-radius: var(--radius-full);
  padding: 5px 12px;
  cursor: pointer;
  transition: var(--transition);
  color: var(--text-main);
  font-size: 0.85rem;
}

.code-chip:hover {
  border-color: var(--primary);
  background: #172338;
}

.code-chip code {
  color: var(--primary);
  font-weight: 800;
  letter-spacing: 1px;
  font-family: monospace;
}

.chip-tag {
  background: rgba(0, 230, 118, 0.15);
  color: var(--primary);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 1px 6px;
  border-radius: 4px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background: var(--primary);
  color: #051a0e;
  box-shadow: 0 4px 16px var(--primary-glow);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 22px rgba(0, 230, 118, 0.4);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-main);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--text-muted);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 6px 14px;
  font-size: 0.85rem;
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1.1rem;
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.5rem;
  cursor: pointer;
}

/* Hero 头部主视觉 */
.hero-section {
  position: relative;
  padding: 70px 0 50px;
  overflow: hidden;
  background: radial-gradient(circle at 50% 20%, rgba(41, 121, 255, 0.08) 0%, rgba(10, 13, 20, 0) 70%);
}

.hero-content {
  text-align: center;
  max-width: 880px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(0, 230, 118, 0.1);
  border: 1px solid rgba(0, 230, 118, 0.3);
  padding: 6px 16px;
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  color: var(--primary);
  margin-bottom: 24px;
}

.hero-badge .dot {
  width: 8px;
  height: 8px;
  background: var(--primary);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--primary);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); opacity: 0.8; }
  50% { transform: scale(1.2); opacity: 1; }
  100% { transform: scale(0.95); opacity: 0.8; }
}

.hero-title {
  font-size: 3rem;
  line-height: 1.25;
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 20px;
}

.hero-title .highlight {
  background: linear-gradient(135deg, #00e676 0%, #00e5ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  font-size: 1.2rem;
  color: var(--text-muted);
  max-width: 720px;
  margin: 0 auto 36px;
  line-height: 1.7;
}

/* 核心转化：邀请码专属卡片 */
.referral-card {
  background: linear-gradient(145deg, #131b2e 0%, #17223b 100%);
  border: 1px solid #2b3956;
  border-radius: var(--radius-lg);
  padding: 24px 32px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  margin: 0 auto 36px;
  max-width: 640px;
  position: relative;
  overflow: hidden;
}

.referral-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent-cyan));
}

.referral-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.referral-card-header h3 {
  font-size: 1.05rem;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

.referral-perk-tag {
  background: rgba(255, 171, 0, 0.15);
  color: var(--accent-gold);
  border: 1px solid rgba(255, 171, 0, 0.3);
  font-size: 0.75rem;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-weight: 600;
}

.referral-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #0d1322;
  border: 1px solid #293854;
  border-radius: var(--radius-md);
  padding: 8px 12px 8px 20px;
  gap: 16px;
  margin-bottom: 20px;
}

.code-wrapper {
  display: flex;
  flex-direction: column;
  text-align: left;
}

.code-wrapper .label {
  font-size: 0.75rem;
  color: var(--text-sub);
}

.code-value {
  font-size: 1.85rem;
  font-weight: 800;
  letter-spacing: 2px;
  color: var(--primary);
  font-family: monospace;
}

.copy-btn {
  background: #1e2a44;
  color: var(--text-main);
  border: 1px solid #36486c;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}

.copy-btn:hover {
  background: var(--primary);
  color: #061910;
  border-color: var(--primary);
}

.referral-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 50px;
  padding-top: 40px;
  border-top: 1px solid var(--border-color);
}

.stat-item h4 {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 4px;
}
.stat-item h4 span {
  color: var(--primary);
}

.stat-item p {
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* 核心模块统一间距 */
.section {
  padding: 80px 0;
}
.section-alt {
  background: var(--bg-secondary);
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 50px;
}

.section-tag {
  color: var(--primary);
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 10px;
  display: block;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
}

/* 为什么选择 OKX 特性网格 */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 30px 24px;
  transition: var(--transition);
  position: relative;
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: #3b82f6;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
}

.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(0, 230, 118, 0.1);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
}

.feature-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 邀请码专属福利展示 */
.perks-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.perk-box {
  background: linear-gradient(180deg, var(--bg-card) 0%, #121827 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px 26px;
  text-align: center;
  position: relative;
}

.perk-box.featured {
  border-color: var(--primary);
  box-shadow: 0 0 30px rgba(0, 230, 118, 0.15);
}

.perk-ribbon {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, var(--primary), var(--accent-cyan));
  color: #061910;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: var(--radius-full);
}

.perk-value {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary);
  margin: 16px 0 8px;
}

.perk-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.perk-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 四步新手注册教程流程 */
.steps-container {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  position: relative;
}

.step-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px 20px;
  position: relative;
}

.step-number {
  position: absolute;
  top: 16px;
  right: 16px;
  font-size: 2rem;
  font-weight: 900;
  color: rgba(255, 255, 255, 0.05);
  line-height: 1;
}

.step-badge {
  display: inline-block;
  background: var(--accent-blue);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 2px 10px;
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
}

.step-card:nth-child(2) .step-badge { background: #8b5cf6; }
.step-card:nth-child(3) .step-badge { background: var(--primary); color: #071c10; }
.step-card:nth-child(4) .step-badge { background: var(--accent-gold); color: #1c1202; }

.step-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.step-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.step-tip {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--border-color);
  font-size: 0.8rem;
  color: var(--accent-gold);
}

/* 费率对比表格 */
.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
}

.fee-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

.fee-table th, .fee-table td {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-color);
}

.fee-table th {
  background: #0f1422;
  color: var(--text-muted);
  font-weight: 600;
}

.fee-table tr:last-child td {
  border-bottom: none;
}

.fee-table .highlight-row {
  background: rgba(0, 230, 118, 0.05);
}

.fee-table .highlight-row td {
  font-weight: 700;
  color: var(--primary);
}

.tag-save {
  background: rgba(0, 230, 118, 0.15);
  color: var(--primary);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  margin-left: 8px;
}

/* 官方 App 下载板块 */
.download-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.download-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 32px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.download-card-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 20px;
}

.download-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: #1e2840;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.download-title h3 {
  font-size: 1.25rem;
  font-weight: 700;
}

.download-title p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.download-instructions {
  list-style: none;
  margin-bottom: 24px;
}

.download-instructions li {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.download-instructions li::before {
  content: "✔";
  color: var(--primary);
  font-weight: 700;
}

/* 安全防坑注意警示框 */
.security-alert {
  background: rgba(255, 82, 82, 0.08);
  border: 1px solid rgba(255, 82, 82, 0.3);
  border-radius: var(--radius-md);
  padding: 20px;
  margin-top: 36px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.security-alert .icon {
  font-size: 1.5rem;
  color: var(--danger);
}

.security-alert-text h4 {
  color: var(--danger);
  font-size: 1rem;
  margin-bottom: 6px;
}

.security-alert-text p {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* FAQ 手风琴 */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: #3b82f6;
}

.faq-question {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  color: var(--text-main);
  padding: 20px 24px;
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: var(--transition);
}

.faq-question:focus-visible {
  outline: 2px solid var(--primary);
}

.faq-icon {
  font-size: 1.25rem;
  color: var(--text-muted);
  transition: transform 0.3s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  color: var(--primary);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.35s ease;
  background: rgba(10, 13, 20, 0.4);
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 0 24px 20px;
}

.faq-answer p {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* 底部 CTA 激励区 */
.cta-banner {
  background: linear-gradient(135deg, #101a30 0%, #162544 100%);
  border: 1px solid #2d3c5f;
  border-radius: var(--radius-lg);
  padding: 50px 30px;
  text-align: center;
  position: relative;
  overflow: hidden;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
}

.cta-banner h2 {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 16px;
}

.cta-banner p {
  color: var(--text-muted);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto 30px;
}

/* 网站脚部与免责声明 (核心防飘红与透明度) */
.site-footer {
  background: #080a10;
  border-top: 1px solid var(--border-color);
  padding: 60px 0 30px;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand h4 {
  font-size: 1.15rem;
  color: var(--text-main);
  margin-bottom: 12px;
}

.footer-brand p {
  line-height: 1.7;
  margin-bottom: 16px;
}

.footer-column h5 {
  font-size: 0.95rem;
  color: var(--text-main);
  margin-bottom: 16px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary);
}

/* 显式免责声明与风险警示（严格符合金融与搜索合规） */
.footer-disclaimer-box {
  background: #0c101a;
  border: 1px solid #1a2236;
  border-radius: var(--radius-md);
  padding: 24px;
  margin-bottom: 30px;
  line-height: 1.7;
  font-size: 0.8125rem;
}

.footer-disclaimer-box strong {
  color: var(--text-main);
}

.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid #141a29;
  font-size: 0.8rem;
  color: var(--text-sub);
}

/* 悬浮复制 Toast 提示 */
.toast-notice {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: #00e676;
  color: #051a0e;
  font-weight: 700;
  padding: 12px 28px;
  border-radius: var(--radius-full);
  box-shadow: 0 8px 24px rgba(0, 230, 118, 0.4);
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  align-items: center;
  gap: 8px;
}

.toast-notice.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
  visibility: visible;
}

/* 移动端底部固定粘性栏 (提高移动端转化) */
.mobile-sticky-bar {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(10, 13, 20, 0.95);
  backdrop-filter: blur(10px);
  border-top: 1px solid var(--border-color);
  padding: 10px 16px;
  z-index: 99;
  justify-content: space-between;
  align-items: center;
}

.mobile-code-info {
  display: flex;
  flex-direction: column;
}

.mobile-code-info span {
  font-size: 0.7rem;
  color: var(--text-sub);
}

.mobile-code-info strong {
  font-size: 1.1rem;
  color: var(--primary);
  font-family: monospace;
}

/* 正文开篇章节导读速览组件 (取代原先沉重的吸顶双层导航，彻底消除拥挤感) */
.article-toc-box {
  background: linear-gradient(145deg, #111726 0%, #162035 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 22px 26px;
  margin: 32px 0 45px;
}

.article-toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.article-toc-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

.article-toc-hint {
  font-size: 0.8rem;
  color: var(--text-sub);
}

.article-toc-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  list-style: none;
}

.subnav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 8px 14px;
  background: var(--bg-card);
  border: 1px solid #1f2a3f;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
}

.subnav-link span {
  color: var(--primary);
  font-weight: 800;
  font-size: 0.75rem;
  font-family: monospace;
}

.subnav-link:hover {
  color: #fff;
  border-color: var(--primary);
  background: #182338;
  transform: translateY(-2px);
}

@media (max-width: 992px) {
  .article-toc-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 576px) {
  .article-toc-grid {
    grid-template-columns: 1fr;
  }
}

/* 编者独立性政策卡片 (核心防社交工程) */
.editorial-card {
  background: linear-gradient(135deg, #111827 0%, #162238 100%);
  border: 1px solid #2d3b55;
  border-radius: var(--radius-lg);
  padding: 24px 30px;
  margin: 30px 0 50px;
  display: flex;
  gap: 24px;
  align-items: center;
}

.editorial-badge {
  background: rgba(41, 121, 255, 0.15);
  border: 1px solid rgba(41, 121, 255, 0.4);
  color: var(--accent-cyan);
  padding: 8px 16px;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  font-weight: 700;
  white-space: nowrap;
  text-align: center;
}

.editorial-text h4 {
  font-size: 1.1rem;
  margin-bottom: 6px;
  color: var(--text-main);
}

.editorial-text p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 深度干货文章排版通用类 */
.article-block {
  margin-bottom: 60px;
}

.article-title {
  font-size: 1.7rem;
  font-weight: 800;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-main);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-color);
}

.article-title .num {
  background: linear-gradient(135deg, var(--primary), var(--accent-cyan));
  color: #051a0e;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 900;
  flex-shrink: 0;
}

.article-lead {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.8;
  margin-bottom: 24px;
}

/* Callout 信息提示框体系 */
.callout {
  padding: 20px 24px;
  border-radius: var(--radius-md);
  margin: 24px 0;
  border-left: 4px solid;
  line-height: 1.7;
  font-size: 0.95rem;
}

.callout-info {
  background: rgba(41, 121, 255, 0.08);
  border-color: var(--accent-blue);
  color: #cbd5e1;
}

.callout-warning {
  background: rgba(255, 171, 0, 0.08);
  border-color: var(--accent-gold);
  color: #fde68a;
}

.callout-security {
  background: rgba(255, 82, 82, 0.08);
  border-color: var(--danger);
  color: #fca5a5;
}

.callout-success {
  background: rgba(0, 230, 118, 0.08);
  border-color: var(--primary);
  color: #bbf7d0;
}

.callout-title {
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 深度卡片网络 */
.deep-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin: 24px 0;
}

.deep-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin: 24px 0;
}

.deep-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: var(--transition);
}

.deep-card:hover {
  border-color: #3b82f6;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
}

.deep-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.deep-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
}

.deep-card p {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 12px;
}

.deep-card p:last-child {
  margin-bottom: 0;
}

/* C2C 防冻卡 Checklist 列表 */
.safety-checklist {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin: 20px 0;
}

.safety-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.safety-item-icon {
  font-size: 1.25rem;
  flex-shrink: 0;
  margin-top: 2px;
}

.safety-item-content h5 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--text-main);
}

.safety-item-content p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 交互式手续费节省计算器 */
.calc-box {
  background: linear-gradient(145deg, #101726 0%, #17233a 100%);
  border: 1px solid #283752;
  border-radius: var(--radius-lg);
  padding: 32px;
  margin: 36px 0;
  box-shadow: var(--shadow-lg);
}

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
}

.calc-controls {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.calc-label {
  font-size: 0.95rem;
  color: var(--text-main);
  font-weight: 600;
  display: flex;
  justify-content: space-between;
}

.calc-label span {
  color: var(--accent-cyan);
  font-family: monospace;
  font-size: 1.1rem;
}

.calc-slider {
  width: 100%;
  -webkit-appearance: none;
  appearance: none;
  height: 8px;
  border-radius: 4px;
  background: #23314a;
  outline: none;
  cursor: pointer;
}

.calc-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 10px var(--primary);
  cursor: pointer;
}

.calc-results {
  background: #0b101c;
  border: 1px solid #23314c;
  border-radius: var(--radius-md);
  padding: 24px;
}

.calc-results-title {
  font-size: 0.9rem;
  color: var(--text-sub);
  text-transform: uppercase;
  margin-bottom: 16px;
  letter-spacing: 1px;
}

.calc-stat-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 10px 0;
  border-bottom: 1px solid #1a253a;
}

.calc-stat-row:last-child {
  border-bottom: none;
  padding-top: 16px;
}

.calc-stat-label {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.calc-stat-val {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  font-family: monospace;
}

.calc-stat-val.highlight {
  font-size: 1.6rem;
  color: var(--primary);
  font-weight: 900;
}

/* 技术规格参数小表格 */
.tech-spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin: 16px 0;
}

.tech-spec-table th, .tech-spec-table td {
  padding: 10px 14px;
  border: 1px solid var(--border-color);
}

.tech-spec-table th {
  background: #101625;
  color: var(--text-sub);
  text-align: left;
  width: 30%;
}

.tech-spec-table td {
  background: #141b2c;
  color: var(--text-muted);
}

/* 响应式媒体查询适配 */
@media (max-width: 992px) {
  .hero-title {
    font-size: 2.3rem;
  }
  .perks-grid, .steps-container {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
  .site-nav {
    gap: 16px;
  }
}

@media (max-width: 860px) {
  .site-nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: #0f1422;
    border-bottom: 1px solid var(--border-color);
    flex-direction: column;
    padding: 20px;
    gap: 16px;
    box-shadow: 0 16px 30px rgba(0, 0, 0, 0.6);
  }

  .site-nav.active {
    display: flex;
  }

  .menu-toggle {
    display: block;
  }

  .hero-section {
    padding: 40px 0 30px;
  }

  .hero-title {
    font-size: 1.85rem;
  }

  .hero-desc {
    font-size: 1rem;
  }

  .referral-card {
    padding: 20px 16px;
  }

  .referral-box {
    flex-direction: column;
    align-items: stretch;
    text-align: center;
  }

  .code-wrapper {
    text-align: center;
  }

  .copy-btn {
    justify-content: center;
  }

  .perks-grid, .steps-container {
    grid-template-columns: 1fr;
  }

  .hero-stats {
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }

  .footer-top {
    grid-template-columns: 1fr;
  }

  .mobile-sticky-bar {
    display: flex;
  }

  body {
    padding-bottom: 60px;
  }
}