:root {
  color-scheme: dark;
  --bg: #071120;
  --bg-deep: #050d19;
  --navy: #0f2847;
  --blue: #2563eb;
  --cyan: #0ea5e9;
  --glow: #7dd3fc;
  --white: #ffffff;
  --text: #d1d5db;
  --muted: #94a3b8;
  --line: rgba(148, 163, 184, 0.18);
  --card: rgba(255, 255, 255, 0.06);
  --shadow: 0 18px 55px rgba(1, 6, 16, 0.28), 0 4px 18px rgba(8, 40, 84, 0.15);
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 92px;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

button,
a,
summary {
  -webkit-tap-highlight-color: transparent;
}

svg {
  display: block;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.container {
  width: min(calc(100% - 48px), var(--container));
  margin-inline: auto;
}

.narrow {
  width: min(calc(100% - 48px), 900px);
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--white);
  color: var(--bg);
  transform: translateY(-150%);
  transition: transform 160ms ease;
}

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

.site-header {
  position: fixed;
  z-index: 50;
  inset: 0 0 auto;
  height: 76px;
  border-bottom: 1px solid transparent;
  transition: background-color 260ms ease, border-color 260ms ease, box-shadow 260ms ease;
}

.site-header.scrolled {
  border-color: rgba(148, 163, 184, 0.13);
  background: rgba(5, 13, 25, 0.82);
  box-shadow: 0 8px 28px rgba(1, 6, 16, 0.18);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.nav-shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(calc(100% - 48px), var(--container));
  height: 100%;
  margin-inline: auto;
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: var(--white);
  font-size: 20px;
  font-weight: 800;
  line-height: 1;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 12px 21px;
  border: 1px solid transparent;
  border-radius: 10px;
  font-weight: 700;
  line-height: 1.2;
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.button svg,
.text-link svg {
  width: 19px;
  height: 19px;
  margin-left: 9px;
}

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

.button:focus-visible,
.text-link:focus-visible,
.brand:focus-visible,
.site-footer a:focus-visible,
summary:focus-visible {
  outline: 3px solid rgba(125, 211, 252, 0.72);
  outline-offset: 4px;
}

.button-primary {
  background: linear-gradient(120deg, var(--blue), var(--cyan));
  box-shadow: 0 10px 28px rgba(14, 165, 233, 0.19), inset 0 1px 0 rgba(255,255,255,0.2);
  color: var(--white);
}

.button-primary:hover {
  border-color: rgba(125, 211, 252, 0.65);
  box-shadow: 0 13px 34px rgba(14, 165, 233, 0.3), inset 0 1px 0 rgba(255,255,255,0.24);
}

.button-secondary {
  border-color: rgba(148, 163, 184, 0.32);
  background: rgba(255, 255, 255, 0.055);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.06);
  color: var(--white);
  backdrop-filter: blur(8px);
}

.button-secondary:hover {
  border-color: rgba(125, 211, 252, 0.58);
  background: rgba(125, 211, 252, 0.09);
  box-shadow: 0 8px 28px rgba(14, 165, 233, 0.12), inset 0 1px 0 rgba(255,255,255,0.1);
}

.button-small {
  min-height: 40px;
  padding: 9px 15px;
  font-size: 14px;
}

.button-small svg {
  width: 17px;
  height: 17px;
}

.hero {
  position: relative;
  display: flex;
  min-height: min(760px, 82vh);
  overflow: hidden;
  isolation: isolate;
  padding: 135px 0 78px;
  background:
    linear-gradient(rgba(255,255,255,0.018) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.018) 1px, transparent 1px),
    linear-gradient(145deg, #071120 12%, #09182a 56%, #071120 100%);
  background-size: 64px 64px, 64px 64px, auto;
}

.hero::after {
  content: "";
  position: absolute;
  z-index: -1;
  inset: auto 0 0;
  height: 180px;
  background: linear-gradient(transparent, var(--bg));
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  z-index: -2;
  width: 780px;
  height: 780px;
  border-radius: 50%;
  filter: blur(2px);
  opacity: 0.5;
  pointer-events: none;
}

.glow-one {
  top: -400px;
  left: -220px;
  background: radial-gradient(circle, rgba(37, 99, 235, 0.35) 0, rgba(37, 99, 235, 0.08) 42%, transparent 68%);
  animation: drift-one 16s ease-in-out infinite alternate;
}

.glow-two {
  right: -320px;
  bottom: -340px;
  background: radial-gradient(circle, rgba(14, 165, 233, 0.27) 0, rgba(125, 211, 252, 0.06) 40%, transparent 70%);
  animation: drift-two 19s ease-in-out infinite alternate;
}

@keyframes drift-one {
  from { transform: translate3d(0, 0, 0); }
  to { transform: translate3d(130px, 75px, 0); }
}

@keyframes drift-two {
  from { transform: translate3d(0, 0, 0); }
  to { transform: translate3d(-120px, -65px, 0); }
}

.network-visual {
  position: absolute;
  top: 50%;
  right: max(-120px, calc((100vw - var(--container)) / 2 - 150px));
  width: 560px;
  height: 560px;
  opacity: 0.27;
  transform: translateY(-46%);
  pointer-events: none;
}

.network-ring {
  position: absolute;
  inset: 12%;
  border: 1px solid rgba(125, 211, 252, 0.35);
  border-radius: 50%;
}

.ring-one::before,
.ring-one::after,
.ring-two::before,
.ring-two::after {
  content: "";
  position: absolute;
  background: rgba(125, 211, 252, 0.32);
}

.ring-one::before,
.ring-two::before {
  top: 50%;
  left: -8%;
  width: 116%;
  height: 1px;
}

.ring-one::after,
.ring-two::after {
  top: -8%;
  left: 50%;
  width: 1px;
  height: 116%;
}

.ring-two {
  inset: 27%;
  transform: rotate(45deg);
}

.network-node {
  position: absolute;
  width: 9px;
  height: 9px;
  border: 2px solid rgba(255,255,255,0.9);
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 24px rgba(125,211,252,0.8);
}

.node-one { top: 11%; left: 49%; }
.node-two { right: 11%; top: 49%; }
.node-three { bottom: 17%; left: 24%; }

.hero-content {
  position: relative;
  z-index: 2;
  align-self: center;
}

.eyebrow,
.section-label {
  margin: 0 0 18px;
  color: #7dd3fc;
  font-size: 12px;
  font-weight: 800;
  line-height: 1.3;
  text-transform: uppercase;
  letter-spacing: 0;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
}

.eyebrow span {
  width: 26px;
  height: 1px;
  background: var(--glow);
  box-shadow: 0 0 10px rgba(125,211,252,0.7);
}

.hero h1 {
  margin: 0;
  color: var(--white);
  font-size: clamp(58px, 8vw, 104px);
  font-weight: 850;
  line-height: 1.03;
  letter-spacing: 0;
}

.hero h2 {
  max-width: 800px;
  margin: 24px 0 0;
  color: var(--white);
  font-size: clamp(24px, 3.2vw, 39px);
  font-weight: 650;
  line-height: 1.32;
  letter-spacing: 0;
}

.hero-copy {
  max-width: 710px;
  margin: 24px 0 0;
  color: var(--text);
  font-size: 18px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 36px;
}

.hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 15px 28px;
  margin-top: 42px;
  color: var(--muted);
  font-size: 14px;
}

.hero-facts span {
  display: inline-flex;
  align-items: center;
}

.hero-facts i {
  width: 6px;
  height: 6px;
  margin-right: 9px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 12px rgba(14, 165, 233, 0.7);
}

.section {
  padding: 118px 0;
}

.section h2,
.cta-section h2 {
  margin: 0;
  color: var(--white);
  font-size: clamp(34px, 4.2vw, 50px);
  font-weight: 780;
  line-height: 1.2;
  letter-spacing: 0;
}

.definition {
  background: var(--bg);
}

.definition .lead {
  margin: 30px 0 0;
  color: var(--text);
  font-size: 19px;
  line-height: 2;
}

.definition-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  margin: 54px 0 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.definition-stats div {
  padding: 27px 30px;
  border-right: 1px solid var(--line);
}

.definition-stats div:first-child { padding-left: 0; }
.definition-stats div:last-child { border-right: 0; }

.definition-stats dt {
  color: var(--white);
  font-size: 25px;
  font-weight: 800;
  line-height: 1.2;
}

.definition-stats dd {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.advantages {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 85% 12%, rgba(14, 165, 233, 0.09), transparent 29%),
    radial-gradient(circle at 6% 92%, rgba(37, 99, 235, 0.08), transparent 28%),
    var(--bg-deep);
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 440px);
  align-items: end;
  gap: 50px;
  margin-bottom: 48px;
}

.section-heading > p {
  margin: 0 0 5px;
  color: var(--muted);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.feature-card {
  position: relative;
  min-height: 320px;
  overflow: hidden;
  padding: 30px 26px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--card);
  box-shadow: var(--shadow), inset 0 1px 0 rgba(255,255,255,0.035);
  transition: transform 230ms ease, border-color 230ms ease, box-shadow 230ms ease, background-color 230ms ease;
}

.feature-card::before {
  content: "";
  position: absolute;
  top: -90px;
  right: -90px;
  width: 190px;
  height: 190px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(125,211,252,0.12), transparent 68%);
  opacity: 0;
  transition: opacity 230ms ease;
}

.feature-card:hover {
  border-color: rgba(125, 211, 252, 0.45);
  background: rgba(255,255,255,0.075);
  box-shadow: 0 20px 60px rgba(1, 6, 16, 0.35), 0 0 0 1px rgba(14, 165, 233, 0.08), 0 0 32px rgba(14, 165, 233, 0.09);
  transform: translateY(-6px);
}

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

.icon-box,
.scenario-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--glow);
}

.icon-box {
  width: 48px;
  height: 48px;
  border: 1px solid rgba(125, 211, 252, 0.2);
  border-radius: 10px;
  background: rgba(14, 165, 233, 0.1);
}

.icon-box svg { width: 25px; height: 25px; }

.card-number {
  position: absolute;
  top: 30px;
  right: 25px;
  color: rgba(148, 163, 184, 0.33);
  font-size: 13px;
  font-weight: 700;
}

.feature-card h3 {
  margin: 30px 0 12px;
  color: var(--white);
  font-size: 20px;
  line-height: 1.4;
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.85;
}

.pattern-section {
  position: relative;
  background-color: var(--bg);
  background-image: radial-gradient(rgba(125, 211, 252, 0.13) 0.8px, transparent 0.8px);
  background-size: 24px 24px;
}

.pattern-section::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, var(--bg) 0%, rgba(7,17,32,0.75) 48%, rgba(7,17,32,0.3) 100%);
  pointer-events: none;
}

.scenario-layout {
  position: relative;
  display: grid;
  grid-template-columns: minmax(260px, 0.76fr) minmax(0, 1.24fr);
  gap: 90px;
}

.scenario-intro {
  align-self: start;
  position: sticky;
  top: 120px;
}

.scenario-intro > p:not(.section-label),
.faq-intro > p:not(.section-label) {
  margin: 23px 0 0;
  color: var(--muted);
  font-size: 17px;
}

.text-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  margin-top: 30px;
  color: var(--glow);
  font-weight: 700;
}

.text-link svg { transition: transform 180ms ease; }
.text-link:hover svg { transform: translateX(4px); }

.scenario-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  border-radius: 14px;
  background: var(--line);
  list-style: none;
  overflow: hidden;
}

.scenario-list li {
  display: flex;
  gap: 18px;
  min-height: 160px;
  padding: 29px;
  background: rgba(7, 17, 32, 0.93);
}

.scenario-list li:last-child {
  grid-column: 1 / -1;
}

.scenario-icon {
  flex: 0 0 auto;
  width: 42px;
  height: 42px;
  border-radius: 10px;
  background: rgba(14,165,233,0.1);
}

.scenario-icon svg { width: 23px; height: 23px; }

.scenario-list h3 {
  margin: 0;
  color: var(--white);
  font-size: 18px;
  line-height: 1.45;
}

.scenario-list p {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.7;
}

.faq {
  background:
    radial-gradient(circle at 8% 40%, rgba(37,99,235,0.08), transparent 24%),
    var(--bg-deep);
}

.faq-layout {
  display: grid;
  grid-template-columns: minmax(230px, 0.68fr) minmax(0, 1.32fr);
  gap: 90px;
}

.faq-list {
  border-top: 1px solid var(--line);
}

.faq-list details {
  border-bottom: 1px solid var(--line);
}

.faq-list summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 78px;
  padding: 22px 4px;
  color: var(--white);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.5;
  cursor: pointer;
  list-style: none;
}

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

.faq-list summary i {
  position: relative;
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  border: 1px solid rgba(125,211,252,0.27);
  border-radius: 50%;
  background: rgba(14,165,233,0.07);
}

.faq-list summary i::before,
.faq-list summary i::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 10px;
  height: 1px;
  background: var(--glow);
  transform: translate(-50%, -50%);
  transition: transform 180ms ease;
}

.faq-list summary i::after { transform: translate(-50%, -50%) rotate(90deg); }
.faq-list details[open] summary i::after { transform: translate(-50%, -50%) rotate(0); }

.answer {
  overflow: hidden;
}

.answer p {
  margin: 0;
  padding: 0 50px 26px 4px;
  color: var(--muted);
  line-height: 1.9;
}

.cta-section {
  position: relative;
  overflow: hidden;
  padding: 104px 0;
  background: linear-gradient(125deg, #1d4ed8 0%, #087eae 100%);
  isolation: isolate;
}

.cta-section::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image: linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 52px 52px;
}

.cta-glow {
  position: absolute;
  z-index: -1;
  right: -200px;
  bottom: -400px;
  width: 750px;
  height: 750px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,255,255,0.18), transparent 63%);
}

.cta-content {
  text-align: center;
}

.section-label.light { color: rgba(255,255,255,0.73); }

.cta-section p:not(.section-label) {
  margin: 20px 0 30px;
  color: rgba(255,255,255,0.78);
  font-size: 18px;
}

.button-light {
  background: var(--white);
  color: #123a66;
  box-shadow: 0 13px 35px rgba(2, 21, 47, 0.24);
}

.button-light:hover {
  box-shadow: 0 17px 42px rgba(2, 21, 47, 0.33);
}

.site-footer {
  padding: 27px 0;
  border-top: 1px solid rgba(148,163,184,0.11);
  background: #050c17;
  color: var(--muted);
  font-size: 14px;
}

.footer-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.footer-content p { margin: 0; }
.footer-content a { color: var(--text); transition: color 160ms ease; }
.footer-content a:hover { color: var(--glow); }

.js .reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 650ms ease, transform 650ms ease;
}

.js .reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.card-grid .reveal:nth-child(2),
.scenario-list .reveal:nth-child(2) { transition-delay: 70ms; }
.card-grid .reveal:nth-child(3),
.scenario-list .reveal:nth-child(3) { transition-delay: 140ms; }
.card-grid .reveal:nth-child(4),
.scenario-list .reveal:nth-child(4) { transition-delay: 210ms; }
.scenario-list .reveal:nth-child(5) { transition-delay: 280ms; }

@media (max-width: 980px) {
  .card-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .feature-card { min-height: 285px; }
  .network-visual { right: -230px; opacity: 0.2; }
  .scenario-layout,
  .faq-layout { gap: 55px; }
}

@media (max-width: 760px) {
  .container,
  .narrow,
  .nav-shell { width: min(calc(100% - 32px), var(--container)); }

  .site-header { height: 68px; }
  .button-small span { display: none; }
  .button-small { width: 42px; min-height: 42px; padding: 10px; }
  .button-small svg { margin: 0; width: 19px; height: 19px; }

  .hero {
    min-height: auto;
    padding: 112px 0 45px;
    background-size: 44px 44px, 44px 44px, auto;
  }

  .hero h1 { font-size: clamp(52px, 18vw, 76px); }
  .hero h2 { margin-top: 20px; font-size: 25px; }
  .hero-copy { margin-top: 18px; font-size: 16px; }
  .hero-actions { align-items: stretch; margin-top: 30px; }
  .hero-actions .button { flex: 1 1 190px; }
  .hero-facts { gap: 10px 18px; margin-top: 32px; font-size: 13px; }
  .network-visual { top: 28%; right: -275px; width: 500px; height: 500px; }

  .section { padding: 70px 0; }
  .section h2,
  .cta-section h2 { font-size: 34px; }

  .definition .lead { margin-top: 22px; font-size: 17px; line-height: 1.9; }
  .definition-stats { grid-template-columns: 1fr; margin-top: 38px; }
  .definition-stats div,
  .definition-stats div:first-child {
    padding: 20px 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .definition-stats div:last-child { border-bottom: 0; }

  .section-heading,
  .scenario-layout,
  .faq-layout {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .section-heading { margin-bottom: 34px; }
  .section-heading > p { font-size: 15px; }
  .card-grid { grid-template-columns: 1fr; }
  .feature-card { min-height: 0; }

  .scenario-intro { position: static; }
  .scenario-list { grid-template-columns: 1fr; }
  .scenario-list li,
  .scenario-list li:last-child { grid-column: auto; min-height: 0; padding: 24px 20px; }

  .faq-list summary { min-height: 72px; padding-block: 20px; font-size: 17px; }
  .answer p { padding-right: 8px; }

  .cta-section { padding: 82px 0; }
  .footer-content { align-items: flex-start; flex-direction: column; gap: 8px; }
  .footer-content a {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
  }

  .js .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

@media (max-width: 430px) {
  .hero-actions { flex-direction: column; }
  .hero-actions .button { flex-basis: auto; width: 100%; }
  .hero-facts { flex-direction: column; }
  .section h2,
  .cta-section h2 { font-size: 31px; }
  .feature-card { padding: 25px 22px; }
  .scenario-list li { flex-direction: column; }
}

@media (max-width: 375px) and (max-height: 700px) {
  .site-header { height: 60px; }

  .hero {
    padding: 78px 0 22px;
  }

  .eyebrow,
  .hero-facts {
    display: none;
  }

  .hero h1 {
    font-size: 52px;
  }

  .hero h2 {
    margin-top: 12px;
    font-size: 21px;
    line-height: 1.35;
  }

  .hero-copy {
    margin-top: 12px;
    font-size: 14px;
    line-height: 1.7;
  }

  .hero-actions {
    gap: 8px;
    margin-top: 17px;
  }

  .hero-actions .button {
    min-height: 44px;
    padding-block: 10px;
  }

  .definition {
    padding-top: 52px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
  .js .reveal { opacity: 1; transform: none; }
}

@media (hover: none) {
  .feature-card:hover,
  .button:hover { transform: none; }
}