:root {
  color-scheme: light;
  --ink: #18201f;
  --muted: #64706d;
  --line: #dce6e1;
  --paper: #f7faf8;
  --white: #ffffff;
  --forest: #163f36;
  --teal: #087f8c;
  --mint: #dff5ea;
  --amber: #c98428;
  --coal: #101514;
  --shadow: 0 18px 50px rgba(18, 32, 29, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  letter-spacing: 0;
}

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

img {
  max-width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 74px;
  padding: 14px clamp(18px, 4vw, 56px);
  color: var(--white);
  background: rgba(16, 21, 20, 0.88);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 260px;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 8px;
  overflow: hidden;
}

.brand__logo {
  display: block;
  width: 42px;
  height: 42px;
}

.brand__text {
  display: grid;
  gap: 0;
}

.brand__text strong {
  font-size: 0.96rem;
  line-height: 1.2;
}

.brand__text small {
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.76rem;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 6px;
}

.nav a {
  min-height: 36px;
  padding: 7px 12px;
  color: rgba(255, 255, 255, 0.82);
  border-radius: 6px;
  font-size: 0.9rem;
}

.nav a:hover {
  color: var(--white);
  background: rgba(255, 255, 255, 0.1);
}

.hero {
  position: relative;
  min-height: calc(100vh - 74px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 420px);
  gap: clamp(24px, 5vw, 60px);
  align-items: end;
  padding: clamp(70px, 11vh, 124px) clamp(18px, 6vw, 74px) clamp(34px, 8vh, 72px);
  color: var(--white);
  background:
    linear-gradient(90deg, rgba(12, 18, 17, 0.94) 0%, rgba(12, 18, 17, 0.82) 42%, rgba(12, 18, 17, 0.28) 100%),
    url("/assets/isp-network-hero.png") center / cover no-repeat;
  overflow: hidden;
}

.hero__shade {
  position: absolute;
  inset: auto 0 0;
  height: 32%;
  background: linear-gradient(180deg, rgba(16, 21, 20, 0), rgba(16, 21, 20, 0.9));
  pointer-events: none;
}

.hero__content,
.hero__profile {
  position: relative;
  z-index: 1;
}

.hero__content {
  max-width: 820px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--amber);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.hero h1 {
  max-width: 820px;
  margin: 0;
  font-size: clamp(3rem, 9vw, 7.4rem);
  line-height: 0.94;
  font-weight: 850;
}

.hero__lead {
  max-width: 760px;
  margin: 24px 0 0;
  color: rgba(255, 255, 255, 0.86);
  font-size: 1.12rem;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 18px;
  border-radius: 7px;
  font-weight: 750;
  border: 1px solid transparent;
}

.btn--primary {
  color: var(--coal);
  background: var(--mint);
}

.btn--ghost {
  color: var(--white);
  border-color: rgba(255, 255, 255, 0.32);
  background: rgba(255, 255, 255, 0.08);
}

.hero__stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(120px, 1fr));
  gap: 10px;
  max-width: 760px;
  margin-top: 42px;
}

.stat {
  min-height: 96px;
  padding: 16px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(10px);
}

.stat span,
.stat small {
  display: block;
}

.stat span {
  font-size: 1.05rem;
  font-weight: 820;
}

.stat small {
  margin-top: 8px;
  color: rgba(255, 255, 255, 0.68);
}

.hero__profile {
  align-self: end;
  padding: 22px;
  border-radius: 8px;
  background: rgba(247, 250, 248, 0.92);
  color: var(--ink);
  box-shadow: var(--shadow);
}

.profile-label {
  margin: 0 0 14px;
  color: var(--teal);
  font-weight: 820;
}

.hero__profile dl,
.data-list {
  display: grid;
  gap: 11px;
  margin: 0;
}

.hero__profile dl div,
.data-list div {
  display: grid;
  grid-template-columns: 130px minmax(0, 1fr);
  gap: 14px;
  padding-bottom: 11px;
  border-bottom: 1px solid var(--line);
}

dt {
  color: var(--muted);
  font-size: 0.86rem;
}

dd {
  margin: 0;
  font-weight: 760;
  overflow-wrap: anywhere;
}

.profile-note {
  margin: 16px 0 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.section {
  padding: clamp(56px, 9vw, 100px) clamp(18px, 5vw, 64px);
}

.section--light {
  background: var(--paper);
}

.section--white {
  background: var(--white);
}

.section__inner {
  width: min(1180px, 100%);
  margin: 0 auto;
}

.section__head {
  max-width: 820px;
  margin-bottom: 34px;
}

.section h2 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 4rem);
  line-height: 1.04;
}

.section__intro {
  margin: 18px 0 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.service-card,
.info-card,
.panel,
.network-panel,
.address-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
  box-shadow: 0 1px 0 rgba(20, 42, 37, 0.04);
}

.service-card {
  min-height: 244px;
  padding: 24px;
}

.card-icon {
  display: grid;
  place-items: center;
  width: 42px;
  height: 34px;
  color: var(--forest);
  background: var(--mint);
  border-radius: 7px;
  font-size: 0.8rem;
  font-weight: 850;
}

.service-card h3,
.panel h3,
.info-card h3,
.network-panel h3,
.abuse-band h3 {
  margin: 20px 0 10px;
  font-size: 1.22rem;
  line-height: 1.2;
}

.service-card p,
.info-card p,
.panel p,
.abuse-band p {
  margin: 0;
  color: var(--muted);
}

.network-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(300px, 0.8fr);
  gap: 18px;
}

.route-board {
  min-height: 440px;
  display: grid;
  grid-template-columns: 1fr 60px 1fr 60px 1fr;
  align-items: center;
  padding: clamp(20px, 5vw, 46px);
  border-radius: 8px;
  color: var(--white);
  background:
    linear-gradient(135deg, rgba(22, 63, 54, 0.92), rgba(16, 21, 20, 0.96)),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.04) 0 1px, transparent 1px 90px);
  border: 1px solid rgba(255, 255, 255, 0.16);
}

.route-node {
  min-height: 154px;
  display: grid;
  align-content: center;
  gap: 8px;
  padding: 20px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
}

.route-node span {
  color: var(--mint);
  font-weight: 760;
}

.route-node strong {
  font-size: 1.25rem;
  line-height: 1.2;
}

.route-line {
  height: 2px;
  background: linear-gradient(90deg, rgba(223, 245, 234, 0.2), rgba(223, 245, 234, 0.95));
}

.network-panel {
  padding: 24px;
}

.network-panel h3 {
  margin-top: 0;
}

.network-panel h4 {
  margin: 24px 0 10px;
}

.pill-list,
.compact-list,
.list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.pill-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.pill-list li {
  padding: 7px 10px;
  color: var(--forest);
  background: var(--mint);
  border-radius: 7px;
  font-weight: 760;
  overflow-wrap: anywhere;
}

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

.panel {
  padding: 26px;
}

.panel--accent {
  background: #f2fbf6;
  border-color: #ccebd9;
}

.list {
  display: grid;
  gap: 14px;
}

.list li {
  position: relative;
  padding-left: 22px;
  color: var(--muted);
}

.list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 8px;
  height: 8px;
  background: var(--teal);
  border-radius: 50%;
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.info-card {
  min-height: 238px;
  padding: 24px;
}

.compact-list {
  display: grid;
  gap: 10px;
  color: var(--muted);
}

.text-link {
  display: inline-flex;
  margin-top: 16px;
  color: var(--teal);
  font-weight: 800;
  overflow-wrap: anywhere;
}

.abuse-band {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 420px);
  gap: 24px;
  align-items: center;
  padding: clamp(24px, 5vw, 42px);
  border-radius: 8px;
  color: var(--white);
  background: linear-gradient(135deg, var(--coal), var(--forest));
}

.abuse-band h3 {
  color: var(--white);
}

.abuse-band p {
  color: rgba(255, 255, 255, 0.78);
}

.contact-box {
  display: grid;
  gap: 8px;
  padding: 20px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
}

.contact-box span {
  color: var(--mint);
  font-weight: 800;
}

.contact-box a {
  font-size: 1.35rem;
  font-weight: 850;
  overflow-wrap: anywhere;
}

.contact-box small {
  color: rgba(255, 255, 255, 0.7);
}

.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 380px);
  gap: 18px;
}

.contact-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.contact-list a {
  display: grid;
  gap: 5px;
  min-height: 92px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
}

.contact-list span {
  color: var(--muted);
  font-size: 0.9rem;
}

.contact-list strong {
  color: var(--teal);
  overflow-wrap: anywhere;
}

.address-card {
  display: grid;
  gap: 10px;
  padding: 22px;
  font-style: normal;
}

.address-card span {
  color: var(--muted);
}

.footer {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  padding: 34px clamp(18px, 5vw, 64px);
  color: rgba(255, 255, 255, 0.76);
  background: var(--coal);
}

.footer strong {
  color: var(--white);
}

.footer p {
  margin: 6px 0 0;
}

.footer__links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 12px;
}

.footer__links a {
  color: var(--mint);
}

.fallback-shell {
  background: var(--paper);
}

@media (max-width: 980px) {
  .site-header {
    position: static;
    align-items: flex-start;
    flex-direction: column;
  }

  .brand {
    min-width: 0;
  }

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

  .hero {
    min-height: auto;
    grid-template-columns: 1fr;
    padding-top: 72px;
  }

  .hero h1 {
    font-size: 3.8rem;
  }

  .hero__stats,
  .card-grid,
  .split,
  .info-grid,
  .contact-grid {
    grid-template-columns: 1fr;
  }

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

  .route-board {
    grid-template-columns: 1fr;
    gap: 14px;
    min-height: auto;
  }

  .route-line {
    width: 2px;
    height: 34px;
    justify-self: center;
    background: linear-gradient(180deg, rgba(223, 245, 234, 0.2), rgba(223, 245, 234, 0.95));
  }

  .abuse-band {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 620px) {
  .site-header {
    padding: 14px 16px;
  }

  .brand__text small {
    display: none;
  }

  .nav a {
    padding-left: 8px;
    padding-right: 8px;
  }

  .hero {
    padding: 54px 16px 28px;
  }

  .hero h1 {
    font-size: 3rem;
    line-height: 1;
  }

  .hero__lead,
  .section__intro {
    font-size: 1rem;
  }

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

  .hero__profile dl div,
  .data-list div {
    grid-template-columns: 1fr;
    gap: 3px;
  }

  .section {
    padding: 46px 16px;
  }

  .section h2 {
    font-size: 2.15rem;
  }

  .contact-list {
    grid-template-columns: 1fr;
  }

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

  .footer__links {
    justify-content: flex-start;
  }
}