* {
  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: #1f2937;
  background: #f6f8fc;
  line-height: 1.75;
  overflow-x: hidden;
}

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

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

p {
  margin: 0 0 16px;
}

h1,
h2,
h3 {
  margin: 0 0 16px;
  color: #121827;
  line-height: 1.25;
}

h1 {
  font-size: clamp(34px, 8vw, 64px);
  letter-spacing: -1px;
}

h2 {
  font-size: clamp(26px, 5vw, 42px);
}

h3 {
  font-size: 20px;
}

.container {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(18px);
  border-bottom: 1px solid rgba(220, 226, 238, 0.85);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 22px;
  color: #111827;
  flex: 0 0 auto;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  object-fit: cover;
}

.main-nav {
  display: none;
  position: absolute;
  top: 72px;
  left: 14px;
  right: 14px;
  padding: 16px;
  background: #fff;
  border: 1px solid #e5eaf3;
  box-shadow: 0 18px 48px rgba(20, 28, 45, 0.12);
  border-radius: 22px;
  flex-direction: column;
  gap: 8px;
}

.main-nav a {
  display: block;
  padding: 10px 12px;
  border-radius: 12px;
  color: #4b5563;
  font-size: 15px;
  font-weight: 600;
}

.main-nav a:hover,
.main-nav a.active {
  color: #2980FE;
  background: #f0f6ff;
}

.main-nav .nav-download {
  color: #2980FE;
  background: #edf5ff;
}

.nav-toggle {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.nav-toggle-label {
  width: 44px;
  height: 44px;
  border: 1px solid #e0e7f2;
  border-radius: 14px;
  display: grid;
  place-content: center;
  gap: 5px;
  cursor: pointer;
  background: #fff;
}

.nav-toggle-label span {
  display: block;
  width: 18px;
  height: 2px;
  background: #1f2937;
  border-radius: 10px;
}

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

.gradient-bg,
.vpn-saas-hero,
.cta-section {
  background: linear-gradient(90deg, #3558F2 0%, #7B4EF1 50%, #B84DDA 100%);
}

.vpn-saas-hero {
  position: relative;
  margin: 20px auto 0;
  width: min(1200px, calc(100% - 24px));
  border-radius: 30px;
  overflow: hidden;
  color: #fff;
  isolation: isolate;
}

.vpn-saas-hero::before {
  content: "";
  position: absolute;
  inset: -20% -10% auto auto;
  width: 70%;
  height: 90%;
  background: rgba(255, 255, 255, 0.16);
  transform: skewX(-18deg);
  border-radius: 0 0 0 80px;
  z-index: -1;
}

.vpn-saas-hero::after {
  content: "";
  position: absolute;
  inset: auto -80px -160px auto;
  width: 420px;
  height: 420px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.14);
  z-index: -1;
}

.hero-inner {
  display: grid;
  gap: 34px;
  align-items: center;
  padding: 54px 24px;
}

.hero-copy h1,
.hero-copy p {
  color: #fff;
}

.hero-copy p {
  max-width: 650px;
  font-size: 17px;
  color: rgba(255, 255, 255, 0.88);
}

.hero-tags,
.status-tags,
.inline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 22px 0 26px;
}

.hero-tags span,
.inline-tags span {
  padding: 7px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.14);
  color: #fff;
  font-size: 13px;
  border: 1px solid rgba(255, 255, 255, 0.24);
}

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

.hero-device {
  width: min(420px, 88%);
  border-radius: 34px;
  padding: 14px;
  background: rgba(255, 255, 255, 0.16);
  box-shadow: 0 24px 80px rgba(18, 24, 39, 0.3);
}

.hero-device img {
  border-radius: 28px;
  margin: 0 auto;
}

.float-card {
  position: absolute;
  padding: 10px 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.94);
  color: #172033;
  font-weight: 700;
  box-shadow: 0 18px 45px rgba(18, 24, 39, 0.16);
  font-size: 13px;
}

.float-card.one {
  top: 16px;
  left: 2px;
}

.float-card.two {
  top: 64px;
  right: 0;
}

.float-card.three {
  bottom: 58px;
  left: 6px;
}

.float-card.four {
  bottom: 10px;
  right: 18px;
}

.download-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 13px 24px;
  border-radius: 999px;
  background: #2980FE;
  color: #fff;
  font-weight: 800;
  line-height: 1;
  box-shadow: 0 14px 32px rgba(41, 128, 254, 0.28);
  transition: background .2s ease, transform .2s ease, box-shadow .2s ease;
}

.download-btn:hover {
  background: #1768E8;
  transform: translateY(-2px);
  box-shadow: 0 18px 42px rgba(23, 104, 232, 0.32);
}

.section {
  padding: 72px 0;
}

.section.soft {
  background: #eef4fb;
}

.section-title {
  max-width: 780px;
  margin-bottom: 34px;
}

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

.section-title p,
.lead {
  color: #5c6677;
  font-size: 17px;
}

.product-highlights {
  margin-top: -34px;
  position: relative;
  z-index: 2;
}

.highlight-grid {
  display: grid;
  gap: 16px;
}

.highlight-card,
.info-card,
.risk-card,
.faq-item,
.step-card,
.policy-card,
.article-card,
.check-card,
.tip-box,
.download-panel {
  background: #fff;
  border: 1px solid #e5eaf3;
  border-radius: 26px;
  box-shadow: 0 16px 40px rgba(18, 24, 39, 0.06);
}

.highlight-card {
  padding: 24px;
}

.highlight-card .tag,
.article-badge,
.mini-label {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  padding: 5px 10px;
  border-radius: 999px;
  background: #edf5ff;
  color: #2980FE;
  font-weight: 800;
  font-size: 12px;
  margin-bottom: 12px;
}

.highlight-card p,
.info-card p,
.risk-card p,
.step-card p,
.policy-card p,
.article-card p,
.tip-box p,
.check-card p {
  color: #626b7a;
}

.link-more {
  display: inline-flex;
  margin-top: 8px;
  color: #2980FE;
  font-weight: 800;
}

.feature-split,
.vpn-connection-section,
.high-speed-section,
.global-nodes-section,
.multi-device-section,
.encryption-protocol-section,
.download-layout {
  display: grid;
  gap: 28px;
  align-items: center;
}

.feature-panel {
  background: #fff;
  border: 1px solid #e5eaf3;
  border-radius: 34px;
  padding: 28px;
  box-shadow: 0 20px 60px rgba(18, 24, 39, 0.07);
}

.feature-panel.gradient-card {
  background: linear-gradient(135deg, #ffffff 0%, #f2f6ff 100%);
}

.feature-panel img {
  border-radius: 28px;
  margin: 0 auto;
}

.feature-list {
  display: grid;
  gap: 12px;
  margin: 24px 0 18px;
  padding: 0;
  list-style: none;
}

.feature-list li {
  padding: 12px 14px;
  border-radius: 16px;
  background: #f6f8fc;
  color: #435066;
  border: 1px solid #edf1f7;
}

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

.speed-metrics .metric {
  padding: 18px;
  border-radius: 22px;
  background: #fff;
  border: 1px solid #e4eaf5;
}

.metric strong {
  color: #2980FE;
  display: block;
  font-size: 22px;
}

.node-card-stack {
  display: grid;
  gap: 14px;
}

.node-line {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  border-radius: 18px;
  background: #fff;
  border: 1px solid #e4eaf5;
}

.node-line span:last-child {
  color: #2980FE;
  font-weight: 800;
}

.privacy-protection-section {
  display: grid;
  gap: 24px;
}

.privacy-grid,
.no-log-policy-section,
.encryption-grid,
.risk-grid,
.faq-grid,
.article-grid,
.check-grid {
  display: grid;
  gap: 16px;
}

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

.policy-card {
  border-left: 4px solid #2980FE;
}

.device-stack {
  display: grid;
  gap: 16px;
}

.device-card {
  padding: 18px;
  background: #fff;
  border: 1px solid #e5eaf3;
  border-radius: 24px;
  display: flex;
  gap: 14px;
  align-items: center;
}

.device-card span {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: #edf5ff;
  color: #2980FE;
  font-weight: 900;
}

.protocol-panel {
  background: #121827;
  color: #e5edff;
  border-radius: 34px;
  padding: 28px;
  position: relative;
  overflow: hidden;
}

.protocol-panel::after {
  content: "";
  position: absolute;
  width: 260px;
  height: 260px;
  border-radius: 999px;
  background: linear-gradient(90deg, rgba(53, 88, 242, .32), rgba(184, 77, 218, .28));
  right: -120px;
  top: -120px;
}

.protocol-panel h2,
.protocol-panel h3 {
  color: #fff;
}

.protocol-panel p,
.protocol-panel li {
  color: #cbd5e1;
}

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

.step-card {
  position: relative;
  overflow: hidden;
}

.step-number {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 16px;
  background: #2980FE;
  color: #fff;
  font-weight: 900;
  margin-bottom: 14px;
}

.risk-card {
  border-top: 4px solid #2980FE;
}

.risk-action {
  margin-top: 12px;
  padding: 12px;
  border-radius: 16px;
  background: #f4f8ff;
  color: #344258;
  font-weight: 700;
}

.faq-item details {
  cursor: pointer;
}

.faq-item summary {
  font-weight: 900;
  color: #121827;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item p {
  margin-top: 12px;
  color: #5f6978;
}

.cta-section {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto 72px;
  border-radius: 34px;
  padding: 48px 22px;
  text-align: center;
  color: #fff;
  position: relative;
  overflow: hidden;
}

.cta-section h2,
.cta-section p {
  color: #fff;
}

.cta-section p {
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  color: rgba(255, 255, 255, .88);
}

.page-hero {
  padding: 64px 0 36px;
  background:
    radial-gradient(circle at top right, rgba(123, 78, 241, .16), transparent 28%),
    linear-gradient(180deg, #f8fbff 0%, #f6f8fc 100%);
}

.page-hero .container {
  display: grid;
  gap: 20px;
}

.page-hero h1 {
  max-width: 880px;
  font-size: clamp(34px, 7vw, 56px);
}

.page-hero p {
  max-width: 780px;
  color: #5d6675;
  font-size: 17px;
}

.content-container {
  width: min(1020px, calc(100% - 36px));
  margin: 0 auto;
}

.article-layout {
  display: grid;
  gap: 24px;
  padding: 34px 0 72px;
}

.article-main {
  display: grid;
  gap: 18px;
}

.article-card h2 {
  margin-bottom: 10px;
}

.article-side {
  display: grid;
  gap: 16px;
  align-content: start;
}

.tip-box {
  padding: 22px;
  background: linear-gradient(135deg, #ffffff 0%, #eef6ff 100%);
}

.cta-inline {
  margin-top: 10px;
  padding: 24px;
  border-radius: 28px;
  background: #fff;
  border: 1px solid #e5eaf3;
  text-align: center;
}

.download-layout {
  padding: 34px 0 72px;
}

.download-panel {
  padding: 28px;
}

.install-steps {
  margin: 24px 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.install-steps li {
  padding: 16px;
  border: 1px solid #e5eaf3;
  border-radius: 18px;
  background: #f8fbff;
  color: #445166;
}

.install-steps strong {
  color: #121827;
}

.site-footer {
  background: #101828;
  color: #cbd5e1;
  padding: 54px 0 0;
}

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

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-size: 22px;
  margin-bottom: 12px;
}

.footer-brand img {
  width: 40px;
  height: 40px;
  border-radius: 14px;
  object-fit: cover;
}

.site-footer h3 {
  color: #fff;
  font-size: 16px;
}

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

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

.footer-bottom {
  margin-top: 36px;
  border-top: 1px solid rgba(255,255,255,.12);
  padding: 18px;
  text-align: center;
  color: #a9b4c4;
}

.footer-bottom p {
  margin: 0;
}

@media (min-width: 680px) {
  .highlight-grid,
  .privacy-grid,
  .no-log-policy-section,
  .risk-grid,
  .article-grid,
  .check-grid,
  .faq-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .process-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .hero-inner {
    padding: 66px 42px;
  }
}

@media (min-width: 920px) {
  .nav-toggle-label {
    display: none;
  }

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

  .main-nav a {
    padding: 10px 9px;
    font-size: 14px;
  }

  .hero-inner {
    grid-template-columns: 1.02fr .98fr;
    padding: 76px 58px;
  }

  .feature-split,
  .vpn-connection-section,
  .high-speed-section,
  .global-nodes-section,
  .multi-device-section,
  .encryption-protocol-section,
  .download-layout {
    grid-template-columns: 1fr 1fr;
  }

  .highlight-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .privacy-protection-section {
    grid-template-columns: 1.08fr .92fr;
    align-items: center;
  }

  .risk-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .faq-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .article-layout {
    grid-template-columns: minmax(0, 1fr) 300px;
  }

  .footer-grid {
    grid-template-columns: 1.6fr 1fr 1fr 1fr;
  }
}

@media (min-width: 1080px) {
  .main-nav a {
    padding: 10px 12px;
    font-size: 15px;
  }

  .process-steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 420px) {
  .container,
  .content-container {
    width: min(100% - 24px, 1120px);
  }

  .vpn-saas-hero {
    width: min(100% - 16px, 1200px);
    border-radius: 24px;
  }

  .hero-inner {
    padding: 42px 18px;
  }

  .feature-panel,
  .protocol-panel,
  .download-panel {
    border-radius: 26px;
    padding: 22px;
  }

  .download-btn {
    width: 100%;
  }

  .float-card {
    font-size: 12px;
  }
}