:root {
  --blue: #2980FE;
  --blue-dark: #1768E8;
  --gradient: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
  --text: #1f2937;
  --muted: #64748b;
  --light: #f6f8fc;
  --line: #e5eaf3;
  --white: #ffffff;
  --radius: 24px;
  --shadow: 0 18px 48px rgba(30, 64, 175, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background: #ffffff;
  line-height: 1.75;
  overflow-x: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(226,232,240,.9);
}

.header-inner {
  width: min(1180px, calc(100% - 28px));
  margin: 0 auto;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

.logo,
.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  color: #172554;
  letter-spacing: .02em;
}

.logo img,
.footer-logo img {
  width: 38px;
  height: 38px;
  object-fit: cover;
  border-radius: 12px;
  box-shadow: 0 8px 18px rgba(41,128,254,.15);
}

.nav-toggle {
  display: none;
}

.nav-toggle-label {
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 14px;
  display: grid;
  place-items: center;
  gap: 4px;
  padding: 9px;
  cursor: pointer;
  background: #fff;
}

.nav-toggle-label span {
  display: block;
  width: 20px;
  height: 2px;
  border-radius: 99px;
  background: #1f2937;
}

.site-nav {
  position: absolute;
  left: 16px;
  right: 16px;
  top: 76px;
  display: none;
  flex-direction: column;
  gap: 4px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: #fff;
  box-shadow: var(--shadow);
}

.nav-toggle:checked ~ .site-nav {
  display: flex;
}

.site-nav a {
  padding: 10px 12px;
  color: #334155;
  font-size: 14px;
  border-radius: 12px;
  transition: all .2s ease;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--blue);
  background: #eef5ff;
}

.site-nav .nav-download {
  color: #fff;
  background: var(--blue);
}

.site-nav .nav-download:hover,
.site-nav .nav-download.active {
  color: #fff;
  background: var(--blue-dark);
}

.download-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 13px 26px;
  border-radius: 999px;
  background: var(--blue);
  color: #fff;
  font-weight: 800;
  box-shadow: 0 14px 30px rgba(41,128,254,.28);
  transition: transform .2s ease, background .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
  background: var(--blue-dark);
  transform: translateY(-2px);
  box-shadow: 0 18px 38px rgba(23,104,232,.32);
}

.kicker,
.category-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--blue);
  background: #eef5ff;
  border: 1px solid #dbeafe;
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 13px;
  font-weight: 800;
}

.section {
  padding: 72px 0;
}

.section-soft {
  background: linear-gradient(180deg, #f8fbff 0%, #fff 100%);
}

.section-head {
  max-width: 760px;
  margin-bottom: 28px;
}

.section-head.center {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.section-head h2,
.text-block h2,
.page-title h1 {
  margin: 12px 0 12px;
  line-height: 1.18;
  color: #0f172a;
  font-size: clamp(28px, 4vw, 46px);
}

.section-head p,
.text-block p,
.page-title p {
  color: var(--muted);
  margin: 0;
}

.vpn-network-hero {
  position: relative;
  overflow: hidden;
  background: var(--gradient);
  color: #fff;
  padding: 72px 0 52px;
}

.vpn-network-hero::before,
.vpn-network-hero::after {
  content: "";
  position: absolute;
  border-radius: 999px;
  background: rgba(255,255,255,.16);
  filter: blur(2px);
}

.vpn-network-hero::before {
  width: 520px;
  height: 520px;
  right: -170px;
  top: -180px;
}

.vpn-network-hero::after {
  width: 360px;
  height: 360px;
  left: -180px;
  bottom: -200px;
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 38px;
  align-items: center;
}

.hero-copy h1 {
  font-size: clamp(36px, 8vw, 64px);
  line-height: 1.08;
  margin: 14px 0 18px;
  letter-spacing: -.04em;
}

.hero-copy p {
  color: rgba(255,255,255,.88);
  font-size: 17px;
  max-width: 620px;
  margin-bottom: 24px;
}

.hero-tags,
.floating-tags,
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-tags span,
.floating-tags span,
.tag-row span {
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(255,255,255,.16);
  color: #fff;
  border: 1px solid rgba(255,255,255,.22);
  font-size: 13px;
  font-weight: 700;
}

.hero-art {
  position: relative;
  min-height: 320px;
  display: grid;
  place-items: center;
}

.network-lines {
  position: absolute;
  inset: 0;
  opacity: .7;
  background:
    radial-gradient(circle at 20% 25%, rgba(255,255,255,.85) 0 3px, transparent 4px),
    radial-gradient(circle at 75% 30%, rgba(255,255,255,.7) 0 3px, transparent 4px),
    radial-gradient(circle at 40% 75%, rgba(255,255,255,.7) 0 3px, transparent 4px),
    radial-gradient(circle at 85% 70%, rgba(255,255,255,.75) 0 3px, transparent 4px),
    linear-gradient(30deg, transparent 0 24%, rgba(255,255,255,.28) 25% 26%, transparent 27% 100%),
    linear-gradient(145deg, transparent 0 34%, rgba(255,255,255,.20) 35% 36%, transparent 37% 100%);
}

.hero-device {
  position: relative;
  width: min(420px, 86%);
  padding: 18px;
  border-radius: 32px;
  background: rgba(255,255,255,.18);
  border: 1px solid rgba(255,255,255,.28);
  box-shadow: 0 30px 70px rgba(15,23,42,.24);
}

.hero-device img {
  border-radius: 26px;
  margin: 0 auto;
}

.status-card {
  position: absolute;
  z-index: 2;
  min-width: 132px;
  padding: 12px 14px;
  border-radius: 18px;
  background: rgba(255,255,255,.92);
  color: #172554;
  border: 1px solid rgba(255,255,255,.55);
  box-shadow: 0 16px 40px rgba(15,23,42,.18);
  font-weight: 800;
  font-size: 13px;
}

.status-card small {
  display: block;
  color: var(--muted);
  font-weight: 600;
  margin-top: 2px;
}

.status-one { left: 0; top: 24px; }
.status-two { right: 0; top: 76px; }
.status-three { left: 12px; bottom: 44px; }
.status-four { right: 18px; bottom: 8px; }

.node-overview {
  margin-top: -34px;
  position: relative;
  z-index: 3;
}

.node-overview-grid {
  display: grid;
  gap: 16px;
}

.node-card,
.info-card,
.faq-item,
.risk-card,
.step-card,
.policy-card,
.article-card,
.side-card,
.stat-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: 0 12px 34px rgba(15,23,42,.06);
}

.node-card {
  padding: 22px;
}

.node-card .label {
  display: inline-flex;
  padding: 4px 9px;
  background: #eef5ff;
  color: var(--blue);
  border-radius: 999px;
  font-size: 12px;
  font-weight: 800;
  margin-bottom: 12px;
}

.node-card h3,
.info-card h3,
.risk-card h3,
.step-card h3,
.policy-card h3,
.article-card h2,
.side-card h3,
.stat-card h3 {
  margin: 0 0 8px;
  color: #0f172a;
  line-height: 1.25;
}

.node-card p,
.info-card p,
.risk-card p,
.step-card p,
.policy-card p,
.article-card p,
.side-card p,
.stat-card p {
  color: var(--muted);
  margin: 0;
}

.inline-link,
.node-card a,
.info-card a,
.step-card a,
.risk-card a,
.article-card a,
.side-card a,
.faq-item a {
  display: inline-flex;
  margin-top: 12px;
  color: var(--blue);
  font-weight: 800;
}

.two-column,
.vpn-connection-section,
.global-nodes-section,
.high-speed-section,
.privacy-protection-section,
.multi-device-section,
.encryption-protocol-section {
  display: grid;
  gap: 28px;
  align-items: center;
}

.visual-card {
  border-radius: 32px;
  padding: 20px;
  background: linear-gradient(180deg, #ffffff 0%, #f2f7ff 100%);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.visual-card img {
  border-radius: 24px;
  margin: 0 auto;
}

.feature-list,
.check-list,
.simple-list {
  display: grid;
  gap: 12px;
  padding: 0;
  margin: 18px 0 0;
  list-style: none;
}

.feature-list li,
.check-list li,
.simple-list li {
  position: relative;
  padding-left: 28px;
  color: #334155;
}

.feature-list li::before,
.check-list li::before,
.simple-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 10px;
  height: 10px;
  border-radius: 999px;
  background: var(--blue);
  box-shadow: 0 0 0 5px #eaf3ff;
}

.global-nodes-section {
  position: relative;
  overflow: hidden;
  padding: 32px;
  border-radius: 32px;
  background:
    radial-gradient(circle at 20% 20%, rgba(41,128,254,.16), transparent 26%),
    radial-gradient(circle at 75% 30%, rgba(123,78,241,.14), transparent 28%),
    linear-gradient(180deg, #ffffff 0%, #f6f9ff 100%);
  border: 1px solid var(--line);
}

.map-panel {
  position: relative;
  min-height: 260px;
  border-radius: 28px;
  background:
    radial-gradient(circle at 18% 30%, #2980FE 0 5px, transparent 6px),
    radial-gradient(circle at 72% 24%, #7B4EF1 0 5px, transparent 6px),
    radial-gradient(circle at 46% 66%, #B84DDA 0 5px, transparent 6px),
    radial-gradient(circle at 83% 74%, #2980FE 0 5px, transparent 6px),
    linear-gradient(120deg, transparent 0 32%, rgba(41,128,254,.18) 33% 34%, transparent 35%),
    linear-gradient(35deg, transparent 0 40%, rgba(123,78,241,.16) 41% 42%, transparent 43%),
    #eef5ff;
  display: grid;
  place-items: center;
  padding: 20px;
}

.map-panel img {
  max-height: 260px;
  object-fit: contain;
}

.speed-lines {
  display: grid;
  gap: 12px;
  margin-top: 18px;
}

.speed-line {
  padding: 14px 16px;
  border-radius: 18px;
  background: #fff;
  border: 1px solid var(--line);
}

.speed-line strong {
  color: #0f172a;
}

.speed-bar {
  height: 8px;
  border-radius: 99px;
  background: #eaf3ff;
  margin-top: 10px;
  overflow: hidden;
}

.speed-bar span {
  display: block;
  height: 100%;
  border-radius: 99px;
  background: var(--blue);
}

.privacy-panel {
  padding: 28px;
  border-radius: 32px;
  border: 1px solid var(--line);
  background: #fff;
  box-shadow: var(--shadow);
}

.safety-panel {
  display: grid;
  gap: 14px;
  padding: 22px;
  border-radius: 26px;
  background: linear-gradient(180deg, #f8fbff 0%, #fff 100%);
  border: 1px solid var(--line);
}

.safety-row {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  padding: 14px;
  border-radius: 18px;
  background: #fff;
  border: 1px solid var(--line);
}

.safety-row span {
  color: var(--muted);
}

.policy-grid,
.risk-grid,
.faq-grid,
.article-grid,
.stat-grid {
  display: grid;
  gap: 16px;
}

.policy-card,
.info-card,
.risk-card,
.step-card,
.faq-item,
.article-card,
.stat-card {
  padding: 22px;
}

.device-grid {
  display: grid;
  gap: 14px;
}

.device-pill {
  padding: 18px;
  border-radius: 22px;
  background: #fff;
  border: 1px solid var(--line);
  font-weight: 800;
  color: #172554;
}

.protocol-panel {
  border-radius: 32px;
  background: #0f172a;
  color: #fff;
  padding: 24px;
  overflow: hidden;
  position: relative;
}

.protocol-panel::before {
  content: "";
  position: absolute;
  width: 260px;
  height: 260px;
  right: -120px;
  top: -120px;
  border-radius: 999px;
  background: rgba(41,128,254,.28);
}

.protocol-panel img {
  position: relative;
  border-radius: 24px;
  margin: 0 auto 18px;
}

.protocol-list {
  position: relative;
  display: grid;
  gap: 10px;
}

.protocol-list div {
  padding: 12px 14px;
  border-radius: 16px;
  background: rgba(255,255,255,.1);
  border: 1px solid rgba(255,255,255,.12);
}

.process-steps {
  display: grid;
  gap: 16px;
  counter-reset: step;
}

.step-card {
  position: relative;
}

.step-num {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 14px;
  color: #fff;
  background: var(--blue);
  font-weight: 900;
  margin-bottom: 14px;
}

.risk-card {
  border-left: 4px solid var(--blue);
}

.faq-item h3 {
  font-size: 18px;
}

.cta-section {
  padding: 68px 0;
  color: #fff;
  background: var(--gradient);
}

.cta-box {
  width: min(900px, calc(100% - 32px));
  margin: 0 auto;
  text-align: center;
}

.cta-box h2 {
  font-size: clamp(30px, 5vw, 48px);
  line-height: 1.18;
  margin: 0 0 14px;
}

.cta-box p {
  color: rgba(255,255,255,.86);
  margin: 0 auto 24px;
  max-width: 680px;
}

.page-hero {
  padding: 62px 0 40px;
  background: linear-gradient(180deg, #f7faff 0%, #fff 100%);
  border-bottom: 1px solid var(--line);
}

.page-title {
  max-width: 860px;
}

.page-layout {
  display: grid;
  gap: 28px;
  align-items: start;
}

.article-card {
  margin-bottom: 18px;
}

.article-card h2 {
  font-size: 24px;
}

.side-card {
  padding: 22px;
  margin-bottom: 16px;
}

.notice-box {
  padding: 18px;
  border-radius: 22px;
  background: #eef5ff;
  border: 1px solid #dbeafe;
  color: #334155;
}

.download-steps {
  display: grid;
  gap: 14px;
  margin: 24px 0;
}

.download-steps .step-card {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.download-page-cta {
  padding: 28px;
  border-radius: 32px;
  background: linear-gradient(180deg, #f8fbff 0%, #fff 100%);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  text-align: center;
  margin: 24px 0;
}

.about-mission {
  padding: 28px;
  border-radius: 32px;
  background: #fff;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.site-footer {
  background: #0f172a;
  color: #cbd5e1;
  padding-top: 54px;
}

.footer-grid {
  display: grid;
  gap: 28px;
}

.footer-logo {
  color: #fff;
  margin-bottom: 12px;
}

.site-footer h3 {
  color: #fff;
  margin: 0 0 12px;
}

.site-footer a {
  display: block;
  color: #cbd5e1;
  margin: 8px 0;
}

.site-footer a:hover {
  color: #fff;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.1);
  margin-top: 34px;
  padding: 18px 16px;
  text-align: center;
  color: #94a3b8;
}

@media (min-width: 720px) {
  .node-overview-grid,
  .policy-grid,
  .risk-grid,
  .article-grid,
  .stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .process-steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .device-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1.5fr 1fr 1fr 1fr;
  }
}

@media (min-width: 980px) {
  .nav-toggle-label {
    display: none;
  }

  .site-nav {
    position: static;
    display: flex;
    flex-direction: row;
    align-items: center;
    box-shadow: none;
    border: 0;
    background: transparent;
    padding: 0;
    gap: 2px;
  }

  .site-nav a {
    padding: 9px 10px;
  }

  .hero-grid,
  .two-column,
  .vpn-connection-section,
  .high-speed-section,
  .privacy-protection-section,
  .multi-device-section,
  .encryption-protocol-section,
  .page-layout {
    grid-template-columns: 1.05fr .95fr;
  }

  .global-nodes-section {
    grid-template-columns: .9fr 1.1fr;
  }

  .node-overview-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .risk-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .process-steps {
    grid-template-columns: repeat(3, 1fr);
  }

  .faq-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .section {
    padding: 88px 0;
  }

  .vpn-network-hero {
    padding: 96px 0 76px;
  }
}

@media (max-width: 520px) {
  .container {
    width: min(100% - 24px, 1120px);
  }

  .header-inner {
    width: min(100% - 20px, 1180px);
  }

  .section {
    padding: 54px 0;
  }

  .global-nodes-section {
    padding: 20px;
  }

  .status-card {
    position: static;
    margin: 8px;
  }

  .floating-status-wrap {
    display: grid;
    grid-template-columns: 1fr 1fr;
    margin-top: 12px;
  }

  .download-btn {
    width: 100%;
  }

  .hero-copy .download-btn,
  .cta-box .download-btn,
  .download-page-cta .download-btn {
    width: auto;
    min-width: 180px;
  }
}