/**
 * bitznet (bitz-net.sbs) 官方落地页主样式表
 * 模板：056 蓝天云海 | 框架：43 二进制雨 稀疏字符雨
 * 字体：Plus Jakarta Sans / Outfit + Noto Sans SC / PingFang SC
 */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;600;700;800;900&family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=Fira+Code:wght@400;500;600&display=swap');

:root {
  /* 蓝天云海核心色板 */
  --bg-deep: #060F1D;
  --bg-surface: #0A192F;
  --bg-card: rgba(13, 31, 58, 0.72);
  --bg-card-hover: rgba(18, 43, 80, 0.88);
  --bg-glass: rgba(255, 255, 255, 0.04);

  /* 苍穹天蓝与数据光流 */
  --sky-primary: #0284C7;
  --sky-accent: #38BDF8;
  --sky-light: #BAE6FD;
  --sky-cyan: #06B6D4;
  --sky-white: #FFFFFF;
  --sky-ice: #F0F9FF;
  --gold-accent: #F59E0B;
  --emerald-accent: #10B981;

  /* 文字体系 */
  --text-pure: #FFFFFF;
  --text-main: #F1F5F9;
  --text-secondary: #94A3B8;
  --text-dim: #64748B;

  /* 边框与光晕 */
  --border-light: rgba(255, 255, 255, 0.08);
  --border-sky: rgba(56, 189, 248, 0.28);
  --border-sky-glow: 0 0 20px rgba(56, 189, 248, 0.25);
  --shadow-card: 0 16px 40px rgba(2, 10, 24, 0.55);

  /* 字体系统 (与 bitznet.baby 和 bitz-net.lol 保持显著差异) */
  --font-sans: 'Plus Jakarta Sans', 'Outfit', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-display: 'Outfit', 'Plus Jakarta Sans', -apple-system, sans-serif;
  --font-mono: 'Fira Code', 'Space Mono', Consolas, Monaco, monospace;

  /* 布局尺寸 */
  --header-height: 76px;
  --container-max: 1240px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 30px;
  --radius-pill: 9999px;
}

/* 全局重置 */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-deep);
  color: var(--text-main);
  font-family: var(--font-sans);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  overflow-x: hidden;
  line-height: 1.65;
  background: radial-gradient(ellipse at 50% 0%, #0c2340 0%, #060f1d 70%, #030712 100%);
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease, opacity 0.2s ease;
}

img, svg {
  display: block;
  max-width: 100%;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  outline: none;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* 文本渐变与高亮 */
.text-gradient {
  background: linear-gradient(135deg, #FFFFFF 0%, #BAE6FD 50%, #38BDF8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-sky {
  color: var(--sky-accent);
}

/* 统一按钮组件规范：主要按钮统一【立即前往注册】 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 28px;
  font-size: 0.98rem;
  font-weight: 700;
  border-radius: var(--radius-pill);
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: center;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #0284C7 0%, #0EA5E9 50%, #38BDF8 100%);
  color: #FFFFFF;
  box-shadow: 0 4px 20px rgba(14, 165, 233, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.25);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(14, 165, 233, 0.6);
  color: #FFFFFF;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-main);
  border: 1px solid var(--border-sky);
  backdrop-filter: blur(8px);
}

.btn-secondary:hover {
  background: rgba(56, 189, 248, 0.14);
  color: #FFFFFF;
  border-color: var(--sky-accent);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.88rem;
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.08rem;
}

/* ===================================================
   1. 顶部导航栏 (Header)
   =================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  z-index: 100;
  transition: background-color 0.3s ease, backdrop-filter 0.3s ease, border-color 0.3s ease;
  border-bottom: 1px solid transparent;
}

.site-header.scrolled {
  background: rgba(6, 15, 29, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(56, 189, 248, 0.18);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-logo-wrap img,
.brand-logo-wrap svg {
  height: 40px;
  width: auto;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 30px;
  list-style: none;
}

.nav-link {
  font-size: 0.94rem;
  font-weight: 600;
  color: var(--text-secondary);
  position: relative;
  padding: 6px 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--sky-accent);
  transition: all 0.25s ease;
  transform: translateX(-50%);
  border-radius: 2px;
}

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

.nav-link:hover::after {
  width: 100%;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.mobile-toggle-btn {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-light);
  padding: 9px;
}

.mobile-toggle-btn span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: #FFFFFF;
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

/* 移动端菜单抽屉 */
.mobile-nav-drawer {
  position: fixed;
  top: var(--header-height);
  left: 0;
  width: 100%;
  background: rgba(6, 15, 29, 0.98);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(56, 189, 248, 0.2);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 18px;
  transform: translateY(-120%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 99;
}

.mobile-nav-drawer.is-open {
  transform: translateY(0);
}

.mobile-nav-link {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-main);
  padding: 10px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

/* ===================================================
   2. 首屏 Hero 区域 (蓝天云海 + 二进制字符雨)
   =================================================== */
.hero-section {
  position: relative;
  min-height: 94vh;
  padding-top: calc(var(--header-height) + 50px);
  padding-bottom: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-content {
  position: relative;
  z-index: 10;
  text-align: center;
  max-width: 960px;
  margin: 0 auto;
}

.hero-badge-wrap {
  display: flex;
  justify-content: center;
  margin-bottom: 22px;
}

.hero-title {
  font-family: var(--font-display);
  font-size: 3.4rem;
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: -1px;
  margin-bottom: 24px;
}

.hero-title .brand-kw {
  position: relative;
  display: inline-block;
  color: #FFFFFF;
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 36px;
  max-width: 820px;
  margin-left: auto;
  margin-right: auto;
}

.hero-desc strong {
  color: #FFFFFF;
  font-weight: 600;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  margin-bottom: 48px;
  flex-wrap: wrap;
}

/* 核心指标条 (Hero Metrics) */
.hero-metrics-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  padding: 20px 28px;
  background: var(--bg-card);
  border: 1px solid var(--border-sky);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(12px);
}

.metric-item {
  text-align: center;
  border-right: 1px solid rgba(255, 255, 255, 0.08);
}

.metric-item:last-child {
  border-right: none;
}

.metric-number {
  font-family: var(--font-mono);
  font-size: 1.8rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 4px;
}

.metric-number span {
  color: var(--sky-accent);
}

.metric-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* ===================================================
   3. 通用章节头部 (Section Header)
   =================================================== */
section {
  padding: 90px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 56px auto;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 5px 14px;
  border-radius: var(--radius-pill);
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.3);
  color: var(--sky-accent);
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.section-title {
  font-family: var(--font-display);
  font-size: 2.3rem;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 16px;
  color: #FFFFFF;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ===================================================
   4. 专线技术优势区 (#features)
   =================================================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 32px 26px;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--sky-accent), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: var(--border-sky);
  background: var(--bg-card-hover);
  box-shadow: 0 16px 36px rgba(2, 132, 199, 0.15);
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon-box {
  width: 54px;
  height: 54px;
  border-radius: 14px;
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--sky-accent);
  font-size: 1.5rem;
  margin-bottom: 20px;
}

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

.feature-text {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ===================================================
   5. 全球骨干网络模拟与测速 (#network)
   =================================================== */
.network-nodes-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-sky);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(14px);
}

.network-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 28px;
  flex-wrap: wrap;
  gap: 16px;
}

.network-panel-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: #FFFFFF;
}

.network-nodes-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.node-card {
  background: rgba(6, 15, 29, 0.65);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all 0.25s ease;
}

.node-card:hover {
  border-color: var(--sky-accent);
  transform: translateY(-2px);
  background: rgba(14, 40, 75, 0.8);
}

.node-info-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.node-flag {
  font-size: 1.5rem;
}

.node-name {
  font-size: 0.98rem;
  font-weight: 700;
  color: #FFFFFF;
}

.node-type {
  font-size: 0.78rem;
  color: var(--sky-light);
}

.node-ping {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  font-weight: 700;
  color: #34D399;
  display: flex;
  align-items: center;
  gap: 6px;
}

.node-status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: #10B981;
  box-shadow: 0 0 8px #10B981;
}

/* ===================================================
   6. 官方套餐价格区 (#plans)
   =================================================== */
.pricing-controls {
  display: flex;
  justify-content: center;
  margin-bottom: 28px;
}

.billing-switch-wrapper {
  display: inline-flex;
  padding: 5px;
  background: rgba(6, 15, 29, 0.8);
  border: 1px solid var(--border-sky);
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.billing-cycle-btn {
  padding: 10px 22px;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text-secondary);
  border-radius: var(--radius-pill);
  transition: all 0.25s ease;
  display: flex;
  align-items: center;
  gap: 6px;
}

.billing-cycle-btn.active {
  background: linear-gradient(135deg, #0284C7 0%, #38BDF8 100%);
  color: #FFFFFF;
  box-shadow: 0 2px 12px rgba(14, 165, 233, 0.4);
}

.discount-tag {
  font-size: 0.72rem;
  padding: 2px 6px;
  background: #EF4444;
  color: #FFFFFF;
  border-radius: var(--radius-pill);
  font-weight: 800;
}

/* 官方专属优惠码横幅 */
.coupon-banner {
  max-width: 820px;
  margin: 0 auto 40px auto;
  background: linear-gradient(90deg, rgba(2, 132, 199, 0.2) 0%, rgba(56, 189, 248, 0.25) 50%, rgba(2, 132, 199, 0.2) 100%);
  border: 1px dashed rgba(56, 189, 248, 0.5);
  border-radius: var(--radius-md);
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px;
}

.coupon-info-text {
  font-size: 0.95rem;
  color: #FFFFFF;
  font-weight: 600;
}

.coupon-code-pill {
  font-family: var(--font-mono);
  font-weight: 800;
  padding: 3px 10px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 6px;
  color: #BAE6FD;
  letter-spacing: 1px;
}

.copy-coupon-btn {
  padding: 7px 18px;
  font-size: 0.86rem;
  font-weight: 700;
  background: #38BDF8;
  color: #060F1D;
  border-radius: var(--radius-pill);
  transition: all 0.2s ease;
}

.copy-coupon-btn:hover {
  background: #FFFFFF;
  transform: scale(1.04);
}

/* 套餐卡片网格 */
.plans-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}

.plan-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 32px 22px;
  display: flex;
  flex-direction: column;
  transition: all 0.3s ease;
  position: relative;
  backdrop-filter: blur(12px);
}

.plan-card.is-featured {
  border-color: var(--sky-accent);
  background: rgba(14, 42, 80, 0.85);
  box-shadow: 0 12px 40px rgba(14, 165, 233, 0.25), 0 0 20px rgba(56, 189, 248, 0.2);
  transform: translateY(-6px);
}

.featured-ribbon {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, #F59E0B, #D97706);
  color: #FFFFFF;
  font-size: 0.76rem;
  font-weight: 800;
  padding: 4px 14px;
  border-radius: var(--radius-pill);
  letter-spacing: 0.5px;
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.4);
}

.plan-tier-name {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 800;
  color: #FFFFFF;
  margin-bottom: 6px;
}

.plan-tier-subtitle {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
  min-height: 38px;
}

.plan-price-block {
  margin-bottom: 24px;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.plan-currency {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--sky-accent);
  font-weight: 700;
  vertical-align: top;
  margin-right: 2px;
}

.plan-price-num {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 900;
  color: #FFFFFF;
  line-height: 1;
}

.plan-price-period {
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.plan-monthly-equivalent {
  font-size: 0.82rem;
  color: var(--sky-light);
  margin-top: 6px;
}

.plan-features-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 28px;
  flex-grow: 1;
}

.plan-feature-item {
  font-size: 0.88rem;
  color: var(--text-main);
  display: flex;
  align-items: flex-start;
  gap: 8px;
  line-height: 1.5;
}

.check-icon {
  color: var(--sky-accent);
  font-weight: 800;
  flex-shrink: 0;
}

.plan-cta-btn {
  width: 100%;
}

/* ===================================================
   7. 客户端下载与上手指南 (#download)
   =================================================== */
.client-platform-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 48px;
}

.platform-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  text-align: center;
  transition: all 0.3s ease;
}

.platform-card:hover {
  border-color: var(--border-sky);
  transform: translateY(-4px);
  background: var(--bg-card-hover);
}

.platform-icon {
  font-size: 2.2rem;
  margin-bottom: 14px;
}

.platform-name {
  font-size: 1.1rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 6px;
}

.platform-version {
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.platform-download-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 16px;
  width: 100%;
  border-radius: var(--radius-pill);
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.3);
  color: var(--sky-light);
  font-size: 0.86rem;
  font-weight: 600;
  transition: all 0.2s ease;
}

.platform-download-btn:hover {
  background: var(--sky-primary);
  color: #FFFFFF;
  border-color: var(--sky-primary);
}

/* 四步极简教程指引 */
.setup-steps-timeline {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  position: relative;
}

.step-card {
  background: rgba(10, 25, 47, 0.6);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  position: relative;
}

.step-number-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 800;
  color: var(--sky-accent);
  background: rgba(56, 189, 248, 0.14);
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 12px;
}

.step-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 8px;
}

.step-desc {
  font-size: 0.86rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ===================================================
   8. 7 篇原创技术专栏展示区 (#articles)
   =================================================== */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.article-showcase-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 26px 22px;
  display: flex;
  flex-direction: column;
  transition: all 0.3s ease;
}

.article-showcase-card:hover {
  border-color: var(--border-sky);
  transform: translateY(-4px);
  background: var(--bg-card-hover);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
}

.article-meta-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
  font-size: 0.78rem;
}

.article-category-badge {
  color: var(--sky-accent);
  background: rgba(56, 189, 248, 0.12);
  padding: 3px 8px;
  border-radius: 4px;
  font-weight: 600;
}

.article-read-time {
  color: var(--text-dim);
}

.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: 12px;
  color: #FFFFFF;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card-desc {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-read-link {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--sky-accent);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: gap 0.2s ease;
}

.article-read-link:hover {
  gap: 10px;
  color: #FFFFFF;
}

/* ===================================================
   9. 用户评价与反馈区 (#feedback)
   =================================================== */
.feedback-marquee-wrapper {
  overflow: hidden;
  padding: 20px 0;
  mask-image: linear-gradient(to right, transparent, black 15%, black 85%, transparent);
  -webkit-mask-image: linear-gradient(to right, transparent, black 15%, black 85%, transparent);
}

.feedback-marquee-track {
  display: flex;
  gap: 24px;
  width: max-content;
  animation: feedbackScroll 35s linear infinite;
}

.feedback-card {
  width: 340px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 22px;
  flex-shrink: 0;
}

.feedback-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.feedback-avatar {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: linear-gradient(135deg, #0284C7, #38BDF8);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #FFFFFF;
  font-size: 0.95rem;
}

.feedback-user-info {
  display: flex;
  flex-direction: column;
}

.feedback-user-name {
  font-size: 0.92rem;
  font-weight: 700;
  color: #FFFFFF;
}

.feedback-user-tag {
  font-size: 0.74rem;
  color: var(--sky-accent);
}

.feedback-text {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

@keyframes feedbackScroll {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}

.feedback-submit-box {
  margin-top: 36px;
  text-align: center;
}

/* 用户体验反馈弹窗 (Modal) */
.feedback-modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(8px);
  z-index: 999;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.feedback-modal-overlay.is-active {
  display: flex;
}

.feedback-modal-card {
  width: 100%;
  max-width: 500px;
  background: #0B1C33;
  border: 1px solid var(--border-sky);
  border-radius: var(--radius-lg);
  padding: 32px;
  position: relative;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
}

.modal-close-btn {
  position: absolute;
  top: 18px;
  right: 18px;
  color: var(--text-dim);
  font-size: 1.5rem;
  line-height: 1;
}

.modal-close-btn:hover {
  color: #FFFFFF;
}

.feedback-form-group {
  margin-bottom: 18px;
}

.feedback-label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  color: #FFFFFF;
  margin-bottom: 8px;
}

.feedback-input,
.feedback-textarea {
  width: 100%;
  background: rgba(6, 15, 29, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 8px;
  padding: 10px 14px;
  color: #FFFFFF;
  font-size: 0.92rem;
  outline: none;
  font-family: inherit;
}

.feedback-input:focus,
.feedback-textarea:focus {
  border-color: var(--sky-accent);
}

/* ===================================================
   10. 常见问题 FAQ (#faq)
   =================================================== */
.faq-accordion-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: all 0.25s ease;
}

.faq-item.is-expanded {
  border-color: var(--border-sky);
  background: var(--bg-card-hover);
}

.faq-question-btn {
  width: 100%;
  padding: 20px 24px;
  text-align: left;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  color: #FFFFFF;
  font-size: 1.05rem;
  font-weight: 700;
}

.faq-toggle-icon {
  font-size: 1.25rem;
  color: var(--sky-accent);
  transition: transform 0.25s ease;
  flex-shrink: 0;
}

.faq-item.is-expanded .faq-toggle-icon {
  transform: rotate(45deg);
}

.faq-answer-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
  padding: 0 24px;
}

.faq-item.is-expanded .faq-answer-panel {
  max-height: 500px;
  padding-bottom: 22px;
}

.faq-answer-text {
  font-size: 0.94rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.faq-answer-text strong {
  color: #FFFFFF;
}

/* ===================================================
   11. 页脚 (Footer)
   =================================================== */
.site-footer {
  background: #040A14;
  border-top: 1px solid rgba(56, 189, 248, 0.15);
  padding: 70px 0 30px 0;
  position: relative;
}

.footer-top-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 50px;
}

.footer-brand-col p {
  font-size: 0.9rem;
  color: var(--text-dim);
  line-height: 1.7;
  margin-top: 16px;
  margin-bottom: 20px;
  max-width: 340px;
}

.footer-col-title {
  font-size: 1rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 20px;
  letter-spacing: 0.5px;
}

.footer-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 11px;
}

.footer-links-list a {
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.footer-links-list a:hover {
  color: var(--sky-accent);
}

.footer-bottom-bar {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.82rem;
  color: var(--text-dim);
}

.footer-seo-cloud {
  font-size: 0.78rem;
  color: rgba(148, 163, 184, 0.6);
  line-height: 1.8;
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px dashed rgba(255, 255, 255, 0.05);
}

/* ===================================================
   12. 响应式布局适配 (Mobile & Tablet)
   =================================================== */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 2.8rem;
  }
  .features-grid,
  .articles-grid,
  .network-nodes-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .plans-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .client-platform-grid,
  .setup-steps-timeline {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-top-grid {
    grid-template-columns: 1fr 1fr;
    gap: 30px;
  }
}

@media (max-width: 768px) {
  .site-header {
    height: 68px;
  }
  .nav-menu,
  .header-cta-btn {
    display: none;
  }
  .mobile-toggle-btn {
    display: flex;
  }
  .hero-section {
    padding-top: calc(68px + 30px);
    padding-bottom: 40px;
  }
  .hero-title {
    font-size: 2.2rem;
  }
  .hero-desc {
    font-size: 1rem;
  }
  .hero-metrics-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }
  .metric-item:nth-child(2) {
    border-right: none;
  }
  .features-grid,
  .articles-grid,
  .network-nodes-grid,
  .plans-grid,
  .client-platform-grid,
  .setup-steps-timeline {
    grid-template-columns: 1fr;
  }
  .footer-top-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom-bar {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.85rem;
  }
  .hero-cta-group {
    flex-direction: column;
    width: 100%;
  }
  .hero-cta-group .btn {
    width: 100%;
  }
  .plan-price-num {
    font-size: 2.1rem;
  }
}