:root {
  --bg: #f4f8fb;
  --surface: #ffffff;
  --surface-2: #eaf8fa;
  --ink: #03101f;
  --ink-2: #071b2f;
  --text: #102033;
  --muted: #627386;
  --line: #d7e6ed;
  --brand: #16d8c7;
  --brand-2: #1688ff;
  --accent: #38f1d2;
  --success: #20d692;
  --shadow: 0 18px 44px rgba(3, 16, 31, 0.14);
  color-scheme: light;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    radial-gradient(circle at top left, rgba(22, 216, 199, 0.12), transparent 34rem),
    var(--bg);
  color: var(--text);
  line-height: 1.65;
}

a {
  color: var(--brand);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--brand-2);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid rgba(22, 216, 199, 0.18);
  background: rgba(3, 16, 31, 0.92);
  backdrop-filter: blur(14px);
}

.header-inner {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 68px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 800;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  object-fit: cover;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: var(--ink);
  color: var(--brand);
  font-size: 18px;
  box-shadow: 0 0 0 1px rgba(22, 216, 199, 0.28);
}

.top-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 14px;
  font-size: 14px;
}

.top-nav a {
  color: rgba(255, 255, 255, 0.72);
  font-weight: 650;
  text-decoration: none;
}

.top-nav a[aria-current="page"],
.top-nav a:hover {
  color: var(--brand);
}

.hero {
  position: relative;
  min-height: 520px;
  display: grid;
  align-items: end;
  overflow: hidden;
  color: #fff;
  background: var(--ink);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 74% 42%, rgba(22, 216, 199, 0.18), transparent 20rem),
    linear-gradient(90deg, rgba(3, 16, 31, 0.96), rgba(3, 16, 31, 0.76) 42%, rgba(3, 16, 31, 0.24));
  z-index: 1;
}

.hero > img:not(.hero-visual) {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.42;
}

.hero-content {
  position: relative;
  z-index: 2;
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 86px 0 80px;
}

.hero-visual {
  position: absolute;
  right: max(24px, calc((100vw - 1180px) / 2));
  bottom: 44px;
  z-index: 2;
  width: min(410px, 38vw);
  height: auto;
  border: 1px solid rgba(22, 216, 199, 0.3);
  border-radius: 8px;
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.35);
}

.eyebrow {
  color: var(--brand);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.15;
  letter-spacing: 0;
}

h1 {
  margin: 12px 0 18px;
  max-width: 720px;
  font-size: clamp(40px, 7vw, 76px);
}

.hero p {
  max-width: 650px;
  margin: 0 0 28px;
  color: rgba(255, 255, 255, 0.88);
  font-size: 20px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 18px;
  border: 1px solid transparent;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #fff;
  font-weight: 800;
  text-decoration: none;
}

.button.secondary {
  border-color: rgba(22, 216, 199, 0.42);
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
}

.page {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 42px 0 70px;
}

.doc-layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 42px;
}

.sidebar {
  align-self: start;
  position: sticky;
  top: 92px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.sidebar-title {
  margin: 0 0 12px;
  color: var(--brand-2);
  font-size: 13px;
  font-weight: 850;
  text-transform: uppercase;
}

.sidebar a {
  display: block;
  padding: 7px 0;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
}

.sidebar a[aria-current="page"],
.sidebar a:hover {
  color: var(--brand);
}

.article {
  max-width: 820px;
}

.article-header {
  margin-bottom: 28px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

.breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--brand-2);
}

.breadcrumbs span::before {
  content: "->";
  margin-right: 8px;
  color: var(--brand-2);
}

.article-header h1 {
  margin: 8px 0 14px;
  color: var(--ink-2);
  font-size: clamp(34px, 5vw, 56px);
}

.lead {
  margin: 0;
  color: var(--muted);
  font-size: 20px;
}

.article-illustration {
  margin: 26px 0 30px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(3, 16, 31, 0.06);
}

.article-illustration svg {
  display: block;
  width: 100%;
  height: auto;
}

.article-illustration figcaption {
  margin-top: 12px;
  color: var(--muted);
  font-size: 15px;
  text-align: center;
}

.article h2 {
  margin: 38px 0 12px;
  color: var(--ink-2);
  font-size: 28px;
}

.article h3 {
  margin: 28px 0 10px;
  color: var(--text);
  font-size: 21px;
}

.article p,
.article li {
  font-size: 17px;
}

.article ul,
.article ol {
  padding-left: 24px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin-top: 28px;
}

.card {
  display: flex;
  flex-direction: column;
  min-height: 190px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(3, 16, 31, 0.06);
  text-decoration: none;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.card-number {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: var(--ink);
  color: var(--brand);
  font-weight: 850;
}

.card h2,
.card h3 {
  margin: 18px 0 8px;
  color: var(--ink-2);
  font-size: 22px;
}

.card p {
  margin: 0;
  color: var(--muted);
}

.callout {
  margin: 26px 0;
  padding: 20px;
  border-left: 4px solid var(--brand);
  border-radius: 8px;
  background: var(--surface-2);
}

.callout strong {
  color: var(--brand-2);
}

.connection-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(92px, 0.8fr) minmax(0, 1.2fr) minmax(70px, 0.7fr) minmax(0, 1fr);
  align-items: center;
  gap: 12px;
  margin: 26px 0;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(3, 16, 31, 0.06);
}

.connection-flow.traffic-path {
  grid-template-columns: minmax(0, 1fr) minmax(54px, 0.5fr) minmax(0, 1fr) minmax(54px, 0.5fr) minmax(0, 1fr) minmax(54px, 0.5fr) minmax(0, 1fr);
}

.flow-node {
  display: grid;
  justify-items: center;
  gap: 8px;
  color: var(--ink-2);
  font-weight: 850;
  text-align: center;
}

.flow-node svg {
  width: 42px;
  height: 42px;
  padding: 9px;
  border-radius: 8px;
  background: var(--surface-2);
  fill: none;
  stroke: var(--brand-2);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.flow-link {
  position: relative;
  min-height: 2px;
  background: linear-gradient(90deg, var(--brand), var(--brand-2));
}

.flow-link::after {
  content: "";
  position: absolute;
  right: -1px;
  top: 50%;
  width: 10px;
  height: 10px;
  border-top: 2px solid var(--brand-2);
  border-right: 2px solid var(--brand-2);
  transform: translateY(-50%) rotate(45deg);
  background: var(--surface);
}

.flow-link span {
  position: absolute;
  left: 50%;
  top: -32px;
  transform: translateX(-50%);
  width: max-content;
  max-width: 130px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 750;
  text-align: center;
}

.steps {
  counter-reset: steps;
  list-style: none;
  padding: 0;
}

.steps li {
  counter-increment: steps;
  position: relative;
  margin: 12px 0;
  padding: 16px 18px 16px 58px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.steps li::before {
  content: counter(steps);
  position: absolute;
  left: 16px;
  top: 15px;
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #fff;
  font-size: 14px;
  font-weight: 850;
}

.comparison {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin: 18px 0;
}

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

.access-table-wrap {
  margin: 24px 0;
  overflow-x: auto;
}

.access-table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(3, 16, 31, 0.06);
}

.access-table caption {
  margin-bottom: 10px;
  color: var(--muted);
  font-size: 15px;
  font-weight: 750;
  text-align: left;
}

.access-table th,
.access-table td {
  padding: 14px;
  border-bottom: 1px solid var(--line);
  border-right: 1px solid var(--line);
  text-align: center;
  vertical-align: middle;
}

.access-table th {
  background: var(--surface-2);
  color: var(--ink-2);
  font-size: 14px;
  font-weight: 850;
}

.access-table th:first-child,
.access-table td:first-child {
  text-align: left;
}

.access-table tr:last-child td {
  border-bottom: 0;
}

.access-table th:last-child,
.access-table td:last-child {
  border-right: 0;
}

.access-mark {
  display: inline-grid;
  place-items: center;
  min-width: 34px;
  height: 28px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 850;
}

.access-yes {
  background: rgba(32, 214, 146, 0.14);
  color: #08794e;
}

.access-partial {
  background: rgba(22, 136, 255, 0.12);
  color: var(--brand-2);
}

.access-no {
  background: rgba(98, 115, 134, 0.12);
  color: var(--muted);
}

.diagram-caption {
  margin-top: -10px;
  color: var(--muted);
  font-size: 15px;
}

.envelope-flow {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  align-items: center;
  gap: 12px;
  margin: 26px 0 12px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(3, 16, 31, 0.06);
}

.envelope-node {
  position: relative;
  display: grid;
  justify-items: center;
  gap: 8px;
  color: var(--ink-2);
  font-weight: 850;
  text-align: center;
}

.envelope-node:not(:last-child)::after {
  content: "";
  position: absolute;
  right: -14px;
  top: 21px;
  width: 18px;
  height: 2px;
  background: linear-gradient(90deg, var(--brand), var(--brand-2));
}

.envelope-node:not(:last-child)::before {
  content: "";
  position: absolute;
  right: -15px;
  top: 17px;
  width: 9px;
  height: 9px;
  border-top: 2px solid var(--brand-2);
  border-right: 2px solid var(--brand-2);
  transform: rotate(45deg);
}

.envelope-node svg {
  width: 42px;
  height: 42px;
  padding: 9px;
  border-radius: 8px;
  background: var(--surface-2);
  fill: none;
  stroke: var(--brand-2);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.mini-card {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.mini-card h3 {
  margin-top: 0;
}

.mini-card ul {
  margin-bottom: 0;
}

.next-card {
  margin-top: 34px;
}

.next-card .card-number {
  width: auto;
  padding: 0 10px;
}

.pager {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.pager a {
  display: inline-flex;
  max-width: 48%;
  color: var(--ink-2);
  font-weight: 800;
  text-decoration: none;
}

.pager a:last-child {
  text-align: right;
}

.site-footer {
  border-top: 1px solid var(--line);
  background: var(--ink);
}

.footer-inner {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 26px 0;
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
}

.section-band {
  background: var(--surface);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 36px;
  align-items: center;
}

.section-copy {
  max-width: 760px;
}

.section-copy h2 {
  margin: 0 0 14px;
  color: var(--ink-2);
  font-size: clamp(30px, 4vw, 46px);
}

.section-copy p {
  color: var(--muted);
  font-size: 18px;
}

.brand-card {
  width: 100%;
  border: 1px solid rgba(22, 216, 199, 0.24);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.question-list {
  display: grid;
  gap: 12px;
  margin-top: 22px;
}

.question-list a {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--text);
  font-weight: 750;
  text-decoration: none;
}

.question-list a::after {
  content: "->";
  color: var(--brand-2);
}

.article-note {
  color: var(--muted);
  font-size: 15px;
}

@media (max-width: 860px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    padding: 14px 0;
  }

  .top-nav {
    justify-content: flex-start;
  }

  .hero {
    min-height: 500px;
  }

  .hero-visual {
    display: none;
  }

  .doc-layout {
    grid-template-columns: 1fr;
  }

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

  .sidebar {
    position: static;
  }

  .cards,
  .comparison,
  .comparison.two-column {
    grid-template-columns: 1fr;
  }

  .connection-flow {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .connection-flow.traffic-path {
    grid-template-columns: 1fr;
  }

  .envelope-flow {
    grid-template-columns: 1fr;
    gap: 18px;
  }

  .envelope-node:not(:last-child)::after {
    right: auto;
    top: auto;
    bottom: -14px;
    left: 50%;
    width: 2px;
    height: 18px;
    background: linear-gradient(180deg, var(--brand), var(--brand-2));
  }

  .envelope-node:not(:last-child)::before {
    right: auto;
    top: auto;
    bottom: -15px;
    left: calc(50% - 4px);
    transform: rotate(135deg);
  }

  .flow-link {
    width: 2px;
    min-height: 48px;
    margin: 0 auto;
    background: linear-gradient(180deg, var(--brand), var(--brand-2));
  }

  .flow-link::after {
    right: auto;
    left: 50%;
    top: auto;
    bottom: -1px;
    transform: translateX(-50%) rotate(135deg);
    background: var(--surface);
  }

  .flow-link span {
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    text-align: left;
  }

  .pager {
    flex-direction: column;
  }

  .pager a {
    max-width: none;
  }

  .pager a:last-child {
    text-align: left;
  }
}

@media (max-width: 560px) {
  .hero-content {
    padding: 70px 0 58px;
  }

  .hero p,
  .lead {
    font-size: 18px;
  }
}