:root {
  --slate-950: #13202c;
  --slate-800: #2f4151;
  --slate-600: #637789;
  --slate-400: #9cb0c0;
  --fog: #edf3f6;
  --ice: #f8fbfc;
  --white: #ffffff;
  --line: #d5e0e6;
  --blue: #377da3;
  --blue-dark: #265f7e;
  --aqua: #70aeb9;
  --red: #e83f57;
  --green: #348a76;
  --shadow: 0 24px 70px rgba(47, 71, 87, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--slate-950);
  background: var(--ice);
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  line-height: 1.75;
}

body::before {
  position: fixed;
  z-index: -2;
  inset: 0;
  content: "";
  background:
    radial-gradient(ellipse at 12% 14%, rgba(137, 185, 198, 0.3), transparent 34%),
    radial-gradient(ellipse at 84% 20%, rgba(168, 190, 205, 0.25), transparent 32%),
    linear-gradient(180deg, #f6fafb 0, #eaf1f4 42%, #f8fbfc 100%);
}

body::after {
  position: fixed;
  z-index: -1;
  inset: 0;
  content: "";
  opacity: 0.18;
  background-image: repeating-linear-gradient(115deg, transparent 0 34px, rgba(49, 89, 111, 0.12) 35px 36px);
  mask-image: linear-gradient(#000, transparent 80%);
}

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

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

.skip {
  position: fixed;
  z-index: 100;
  top: 8px;
  left: 8px;
  padding: 8px 13px;
  color: #fff;
  background: var(--slate-950);
  border-radius: 6px;
  transform: translateY(-160%);
}

.skip:focus {
  transform: translateY(0);
}

.wrap {
  width: min(1180px, calc(100% - 44px));
  margin-inline: auto;
}

.topbar {
  border-bottom: 1px solid rgba(188, 206, 215, 0.72);
  color: var(--slate-600);
  background: rgba(238, 244, 247, 0.8);
  font-size: 12px;
}

.topbar-inner {
  display: flex;
  min-height: 34px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.topbar-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.status-light {
  width: 7px;
  height: 7px;
  background: var(--green);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(52, 138, 118, 0.12);
}

.header {
  position: sticky;
  z-index: 40;
  top: 0;
  border-bottom: 1px solid rgba(197, 212, 220, 0.8);
  background: rgba(248, 251, 252, 0.9);
  backdrop-filter: blur(20px);
}

.nav {
  display: flex;
  min-height: 72px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 900;
  letter-spacing: 0.02em;
}

.logo-icon {
  display: grid;
  width: 36px;
  height: 36px;
  place-items: center;
  color: #fff;
  background: var(--slate-800);
  border-radius: 50%;
  box-shadow: inset 0 0 0 5px rgba(255, 255, 255, 0.12);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 30px;
  color: #4c6273;
  font-size: 14px;
  font-weight: 700;
}

.nav-list a {
  position: relative;
}

.nav-list a::after {
  position: absolute;
  right: 0;
  bottom: -9px;
  left: 0;
  height: 2px;
  content: "";
  background: var(--blue);
  transform: scaleX(0);
  transition: transform 0.2s ease;
}

.nav-list a:hover::after,
.nav-list a[aria-current="page"]::after {
  transform: scaleX(1);
}

.nav-side {
  display: flex;
  align-items: center;
  gap: 12px;
}

.lang {
  color: var(--slate-600);
  font-size: 12px;
  font-weight: 700;
}

.button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 18px;
  border: 1px solid transparent;
  border-radius: 7px;
  font-size: 14px;
  font-weight: 900;
  line-height: 1.2;
  transition: 0.2s ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-main {
  color: #fff;
  background: var(--slate-800);
  box-shadow: 0 10px 26px rgba(31, 53, 69, 0.2);
}

.button-blue {
  color: #fff;
  background: var(--blue);
  box-shadow: 0 10px 26px rgba(55, 125, 163, 0.22);
}

.button-quiet {
  color: var(--slate-800);
  background: rgba(255, 255, 255, 0.64);
  border-color: var(--line);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  color: var(--slate-800);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 7px;
  font-size: 20px;
}

.hero {
  position: relative;
  padding: 70px 0 50px;
  overflow: hidden;
}

.hero-layout {
  display: grid;
  align-items: center;
  grid-template-columns: minmax(0, 1.07fr) minmax(390px, 0.93fr);
  gap: 72px;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 18px;
  color: var(--blue-dark);
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.kicker::before {
  width: 30px;
  height: 1px;
  content: "";
  background: var(--blue);
}

.hero h1,
.inner-hero h1 {
  margin: 0;
  font-family: "Microsoft YaHei UI", "Microsoft YaHei", sans-serif;
  font-size: clamp(44px, 6.2vw, 74px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.055em;
}

.hero h1 em {
  color: var(--blue);
  font-style: normal;
}

.lead {
  max-width: 650px;
  margin: 22px 0 0;
  color: var(--slate-600);
  font-size: 17px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 11px;
  margin-top: 30px;
}

.hero-footnote {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-top: 22px;
  color: #708393;
  font-size: 12px;
  font-weight: 700;
}

.hero-footnote span::before {
  margin-right: 6px;
  color: var(--green);
  content: "●";
  font-size: 8px;
}

.fog-frame {
  position: relative;
  min-height: 490px;
}

.fog-circle {
  position: absolute;
  inset: 20px 8px 20px 8px;
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 45%, rgba(255, 255, 255, 0.9), rgba(204, 222, 230, 0.58) 57%, rgba(151, 180, 194, 0.35) 71%, transparent 72%);
  border-radius: 50%;
}

.fog-circle::before,
.fog-circle::after {
  position: absolute;
  width: 130%;
  height: 90px;
  left: -15%;
  content: "";
  background: rgba(255, 255, 255, 0.44);
  border-radius: 50%;
  filter: blur(16px);
}

.fog-circle::before {
  top: 25%;
  transform: rotate(-8deg);
}

.fog-circle::after {
  bottom: 17%;
  transform: rotate(7deg);
}

.hero-rocket {
  position: absolute;
  z-index: 2;
  width: 74%;
  max-height: 410px;
  top: 50%;
  left: 50%;
  object-fit: contain;
  filter: saturate(0.82) drop-shadow(0 26px 28px rgba(42, 69, 86, 0.18));
  transform: translate(-50%, -50%);
}

.signal {
  position: absolute;
  z-index: 4;
  padding: 12px 15px;
  color: #40586a;
  background: rgba(248, 251, 252, 0.84);
  border: 1px solid rgba(193, 211, 220, 0.84);
  border-radius: 8px;
  box-shadow: var(--shadow);
  font-size: 11px;
  font-weight: 700;
  backdrop-filter: blur(13px);
}

.signal strong {
  display: block;
  color: var(--slate-950);
  font-size: 15px;
}

.signal-top {
  top: 10px;
  right: 0;
}

.signal-bottom {
  bottom: 20px;
  left: 0;
}

.assurance {
  display: grid;
  margin-top: 26px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.66);
  border: 1px solid var(--line);
  border-radius: 10px;
  box-shadow: 0 16px 48px rgba(47, 72, 89, 0.08);
  grid-template-columns: repeat(3, 1fr);
}

.assurance-item {
  display: flex;
  min-height: 76px;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: #4a6171;
  font-size: 13px;
  font-weight: 800;
}

.assurance-item + .assurance-item {
  border-left: 1px solid var(--line);
}

.assurance-icon {
  display: grid;
  width: 35px;
  height: 35px;
  place-items: center;
  color: var(--blue-dark);
  background: #e4eef2;
  border-radius: 50%;
  font-size: 12px;
}

.section {
  padding: 88px 0;
}

.section-muted {
  background: rgba(218, 229, 235, 0.46);
  border-block: 1px solid #d7e2e8;
}

.section-dark {
  color: #e8f0f4;
  background:
    radial-gradient(circle at 15% 0, rgba(112, 174, 185, 0.18), transparent 31rem),
    #263744;
}

.section-heading {
  display: grid;
  align-items: end;
  margin-bottom: 38px;
  grid-template-columns: minmax(0, 0.8fr) minmax(280px, 0.45fr);
  gap: 50px;
}

.section-heading.center {
  display: block;
  max-width: 720px;
  margin-inline: auto;
  text-align: center;
}

.section-heading h2 {
  margin: 0;
  font-size: clamp(30px, 4.2vw, 48px);
  line-height: 1.2;
  letter-spacing: -0.04em;
}

.section-heading p {
  margin: 0;
  color: var(--slate-600);
}

.section-heading.center p {
  margin-top: 13px;
}

.section-dark .section-heading p {
  color: #a7bac6;
}

.stats {
  display: grid;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid var(--line);
  border-radius: 10px;
  grid-template-columns: repeat(4, 1fr);
}

.stat {
  padding: 30px;
}

.stat + .stat {
  border-left: 1px solid var(--line);
}

.stat strong {
  display: block;
  color: var(--slate-800);
  font-size: 30px;
  letter-spacing: -0.04em;
}

.stat span {
  color: var(--slate-600);
  font-size: 12px;
  font-weight: 700;
}

.data-note {
  margin: 11px 0 0;
  color: #7e909d;
  font-size: 11px;
  text-align: right;
}

.capabilities {
  display: grid;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--line);
  border-radius: 11px;
  grid-template-columns: repeat(3, 1fr);
}

.capability {
  position: relative;
  padding: 34px;
}

.capability + .capability {
  border-left: 1px solid var(--line);
}

.capability-index {
  color: var(--slate-400);
  font-family: Consolas, monospace;
  font-size: 12px;
}

.capability h3 {
  margin: 42px 0 10px;
  font-size: 21px;
}

.capability p {
  margin: 0;
  color: var(--slate-600);
  font-size: 14px;
}

.capability-link {
  display: inline-block;
  margin-top: 24px;
  color: var(--blue-dark);
  font-size: 12px;
  font-weight: 900;
}

.world-layout {
  display: grid;
  align-items: center;
  grid-template-columns: 0.88fr 1.12fr;
  gap: 68px;
}

.world-image {
  position: relative;
  padding: 13px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.world-image img {
  width: 100%;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: 7px;
  filter: saturate(0.68) contrast(0.95);
}

.city-list {
  display: grid;
  gap: 10px;
}

.city {
  display: grid;
  min-height: 66px;
  align-items: center;
  padding: 13px 17px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(190, 211, 221, 0.15);
  border-radius: 7px;
  grid-template-columns: 1fr auto auto;
  gap: 18px;
}

.city strong {
  color: #fff;
}

.city small {
  color: #9fb3bf;
}

.latency {
  color: #8bd0c3;
  font-family: Consolas, monospace;
  font-size: 12px;
}

.bandwidth {
  padding: 3px 7px;
  color: #cfe0e8;
  background: #354b5a;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 800;
}

.quotes,
.plans,
.download-options,
.help-topics,
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.quote {
  padding: 28px;
  background: rgba(255, 255, 255, 0.74);
  border: 1px solid var(--line);
  border-radius: 9px;
}

.stars {
  color: #d99c2a;
  letter-spacing: 3px;
}

.quote blockquote {
  margin: 17px 0;
  color: #3f5667;
  font-size: 14px;
}

.quote footer {
  display: flex;
  align-items: center;
  gap: 11px;
  color: var(--slate-600);
  font-size: 12px;
}

.portrait {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  color: #fff;
  background: var(--slate-800);
  border-radius: 50%;
  font-weight: 900;
}

.plan {
  position: relative;
  padding: 30px;
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid var(--line);
  border-radius: 10px;
}

.plan.recommended {
  color: #edf5f8;
  background: var(--slate-800);
  border-color: var(--slate-800);
  box-shadow: var(--shadow);
}

.recommend-tag {
  position: absolute;
  top: 17px;
  right: 17px;
  padding: 3px 8px;
  color: var(--slate-950);
  background: #c9dde4;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 900;
}

.plan h3 {
  margin: 0;
}

.plan-price {
  margin: 18px 0 0;
  font-size: 34px;
  font-weight: 900;
}

.plan-price small {
  color: var(--slate-600);
  font-size: 12px;
  font-weight: 500;
}

.recommended .plan-price small,
.recommended li {
  color: #b8cbd5;
}

.plan ul {
  margin: 21px 0 26px;
  padding: 0;
  color: var(--slate-600);
  list-style: none;
  font-size: 13px;
}

.plan li {
  padding: 6px 0;
}

.plan li::before {
  margin-right: 7px;
  color: var(--green);
  content: "✓";
  font-weight: 900;
}

.plan .button {
  width: 100%;
}

.recommended .button {
  color: var(--slate-950);
  background: #e5f0f3;
}

.faq {
  max-width: 880px;
  margin-inline: auto;
}

.faq details {
  margin-bottom: 10px;
  background: rgba(255, 255, 255, 0.74);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.faq summary {
  position: relative;
  padding: 18px 50px 18px 20px;
  cursor: pointer;
  font-weight: 900;
  list-style: none;
}

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

.faq summary::after {
  position: absolute;
  top: 14px;
  right: 20px;
  color: var(--blue);
  content: "+";
  font-size: 24px;
}

.faq details[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 0 20px 19px;
  color: var(--slate-600);
  font-size: 14px;
}

.faq-answer ol {
  margin-bottom: 0;
  padding-left: 20px;
}

.inner-hero {
  padding: 68px 0 46px;
}

.inner-layout {
  display: grid;
  align-items: center;
  grid-template-columns: 1.08fr 0.92fr;
  gap: 64px;
}

.inner-hero h1 {
  font-size: clamp(39px, 5.2vw, 62px);
}

.inner-visual {
  position: relative;
  min-height: 370px;
}

.inner-visual::before {
  position: absolute;
  inset: 20px;
  content: "";
  background: radial-gradient(circle, rgba(177, 204, 214, 0.6), transparent 68%);
  border-radius: 50%;
}

.inner-visual img {
  position: absolute;
  width: 100%;
  height: 100%;
  object-fit: contain;
  filter: saturate(0.72) drop-shadow(0 25px 30px rgba(40, 64, 80, 0.17));
}

.download-options {
  align-items: stretch;
}

.download-card,
.help-topic,
.step {
  padding: 28px;
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid var(--line);
  border-radius: 9px;
}

.download-card {
  display: flex;
  flex-direction: column;
}

.system-icon,
.topic-index {
  display: grid;
  width: 46px;
  height: 46px;
  place-items: center;
  color: var(--blue-dark);
  background: #e0ebef;
  border-radius: 7px;
  font-weight: 900;
}

.download-card h3,
.help-topic h3,
.step h3 {
  margin: 21px 0 8px;
}

.download-card p,
.help-topic p,
.step p {
  margin: 0;
  color: var(--slate-600);
  font-size: 13px;
}

.download-card ul {
  margin: 18px 0 23px;
  padding-left: 18px;
  color: var(--slate-600);
  font-size: 12px;
}

.download-card .button {
  width: 100%;
  margin-top: auto;
}

.steps {
  counter-reset: steps;
}

.step {
  counter-increment: steps;
}

.step::before {
  color: var(--slate-400);
  content: "STEP " counter(steps, decimal-leading-zero);
  font-family: Consolas, monospace;
  font-size: 11px;
  font-weight: 800;
}

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

.help-topic a {
  display: inline-block;
  margin-top: 14px;
  color: var(--blue-dark);
  font-size: 12px;
  font-weight: 900;
}

.article {
  max-width: 830px;
  margin-inline: auto;
}

.article h2 {
  margin: 44px 0 11px;
  font-size: 27px;
}

.article h3 {
  margin: 27px 0 7px;
}

.article p,
.article li {
  color: #536a7a;
}

.notice {
  margin: 27px 0;
  padding: 20px 22px;
  background: rgba(216, 231, 237, 0.76);
  border-left: 3px solid var(--blue);
  border-radius: 0 7px 7px 0;
}

.cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
  padding: 38px 42px;
  color: #fff;
  background: var(--slate-800);
  border-radius: 10px;
  box-shadow: var(--shadow);
}

.cta h2 {
  margin: 0;
}

.cta p {
  margin: 4px 0 0;
  color: #b7c9d3;
}

.footer {
  margin-top: 80px;
  padding: 54px 0 22px;
  color: #9fb0bb;
  background: #182630;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 42px;
}

.footer-intro p {
  max-width: 350px;
  color: #8498a5;
  font-size: 12px;
}

.footer h3 {
  margin: 0 0 14px;
  color: #fff;
  font-size: 13px;
}

.footer-links {
  display: grid;
  gap: 8px;
  font-size: 12px;
}

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

.copyright {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  margin-top: 38px;
  padding-top: 18px;
  border-top: 1px solid #30414d;
  font-size: 11px;
}

@media (max-width: 940px) {
  .nav-toggle {
    display: block;
  }

  .nav-list {
    position: absolute;
    top: 72px;
    right: 22px;
    left: 22px;
    display: none;
    padding: 16px;
    background: #f8fbfc;
    border: 1px solid var(--line);
    border-radius: 8px;
    box-shadow: var(--shadow);
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }

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

  .nav-list a {
    padding: 8px;
  }

  .nav-list a::after,
  .lang,
  .nav-side > .button {
    display: none;
  }

  .hero-layout,
  .world-layout,
  .inner-layout {
    grid-template-columns: 1fr;
  }

  .hero-layout {
    gap: 30px;
  }

  .fog-frame {
    min-height: 430px;
  }

  .section-heading {
    display: block;
  }

  .section-heading p {
    margin-top: 12px;
  }

  .stats,
  .capabilities,
  .quotes,
  .plans,
  .download-options,
  .steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .stat + .stat,
  .capability + .capability {
    border-left: 0;
  }

  .stat:nth-child(even),
  .capability:nth-child(even) {
    border-left: 1px solid var(--line);
  }

  .stat:nth-child(n+3),
  .capability:nth-child(n+3) {
    border-top: 1px solid var(--line);
  }
}

@media (max-width: 630px) {
  .wrap {
    width: min(100% - 26px, 1180px);
  }

  .topbar-inner span:last-child {
    display: none;
  }

  .hero {
    padding-top: 48px;
  }

  .hero h1 {
    font-size: 43px;
  }

  .fog-frame {
    min-height: 370px;
  }

  .assurance,
  .stats,
  .capabilities,
  .quotes,
  .plans,
  .download-options,
  .help-topics,
  .steps {
    grid-template-columns: 1fr;
  }

  .assurance-item {
    justify-content: flex-start;
    padding: 10px 18px;
  }

  .assurance-item + .assurance-item,
  .stat:nth-child(even),
  .capability:nth-child(even) {
    border-left: 0;
  }

  .assurance-item + .assurance-item,
  .stat + .stat,
  .capability + .capability {
    border-top: 1px solid var(--line);
  }

  .section {
    padding: 64px 0;
  }

  .city {
    grid-template-columns: 1fr auto;
  }

  .bandwidth {
    display: none;
  }

  .cta,
  .copyright {
    align-items: flex-start;
    flex-direction: column;
  }

  .cta {
    padding: 28px;
  }

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

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}