:root {
  --ink: #16212a;
  --muted: #63717b;
  --line: #d8e0e6;
  --paper: #f7f9fb;
  --white: #ffffff;
  --cyan: #00aeca;
  --amber: #d6922b;
  --green: #27796a;
  --deep: #08131d;
  --shadow: 0 18px 48px rgba(18, 33, 42, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family:
    Inter, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", Arial,
    sans-serif;
  line-height: 1.6;
}

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
  padding: 0 clamp(20px, 5vw, 64px);
  color: var(--white);
  transition:
    background 180ms ease,
    color 180ms ease,
    box-shadow 180ms ease;
}

.site-header.is-scrolled {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 1px 0 rgba(22, 33, 42, 0.08);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 184px;
}

.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  border: 1px solid currentColor;
  border-radius: 8px;
  color: inherit;
  font-weight: 800;
}

.brand strong,
.brand small {
  display: block;
  line-height: 1.2;
}

.brand small {
  margin-top: 2px;
  color: currentColor;
  font-size: 12px;
  opacity: 0.72;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(16px, 2.4vw, 32px);
  font-size: 14px;
}

.site-nav a {
  opacity: 0.86;
}

.site-nav a:hover {
  opacity: 1;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid currentColor;
  border-radius: 8px;
  color: inherit;
  background: transparent;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 5px auto;
  background: currentColor;
}

.hero {
  position: relative;
  min-height: 88vh;
  overflow: hidden;
  color: var(--white);
  background: var(--deep);
}

.hero-image {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(5, 12, 18, 0.86), rgba(5, 12, 18, 0.52) 42%, rgba(5, 12, 18, 0.12)),
    linear-gradient(0deg, rgba(5, 12, 18, 0.86), rgba(5, 12, 18, 0.04) 42%);
}

.hero-content {
  position: relative;
  z-index: 2;
  width: min(760px, calc(100% - 40px));
  padding: 22vh 0 220px clamp(20px, 7vw, 92px);
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--cyan);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 680px;
  margin-bottom: 24px;
  font-size: clamp(38px, 5vw, 68px);
  line-height: 1.08;
  letter-spacing: 0;
}

.hero-copy {
  max-width: 640px;
  margin-bottom: 34px;
  color: rgba(255, 255, 255, 0.82);
  font-size: clamp(16px, 1.5vw, 19px);
}

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

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 22px;
  border: 1px solid rgba(255, 255, 255, 0.42);
  border-radius: 8px;
  font-weight: 700;
}

.button.primary {
  border-color: var(--cyan);
  color: var(--deep);
  background: var(--cyan);
}

.button.secondary {
  color: var(--white);
  background: rgba(255, 255, 255, 0.08);
}

.hero-metrics {
  position: absolute;
  right: clamp(20px, 5vw, 64px);
  bottom: 28px;
  left: clamp(20px, 5vw, 64px);
  z-index: 2;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid rgba(255, 255, 255, 0.18);
  background: rgba(8, 19, 29, 0.42);
  backdrop-filter: blur(18px);
}

.hero-metrics div {
  min-height: 96px;
  padding: 22px 24px;
  border-right: 1px solid rgba(255, 255, 255, 0.16);
}

.hero-metrics div:last-child {
  border-right: 0;
}

.hero-metrics strong {
  display: block;
  font-size: 22px;
}

.hero-metrics span {
  color: rgba(255, 255, 255, 0.68);
  font-size: 14px;
}

.section {
  padding: clamp(72px, 9vw, 120px) clamp(20px, 6vw, 76px);
}

.section-heading {
  max-width: 760px;
  margin-bottom: 34px;
}

.section-heading h2,
.contact h2 {
  margin-bottom: 14px;
  font-size: clamp(30px, 3.2vw, 46px);
  line-height: 1.16;
  letter-spacing: 0;
}

.section-heading p:not(.eyebrow),
.contact p {
  color: var(--muted);
  font-size: 17px;
}

.intro-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.intro-grid article,
.feature-card,
.news-list article {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
  box-shadow: 0 1px 0 rgba(22, 33, 42, 0.04);
}

.intro-grid article {
  min-height: 280px;
  padding: 30px;
}

.index {
  display: block;
  margin-bottom: 42px;
  color: var(--amber);
  font-size: 13px;
  font-weight: 800;
}

h3 {
  margin-bottom: 12px;
  font-size: 22px;
  line-height: 1.28;
}

.intro-grid p,
.feature-card p,
.news-list p {
  color: var(--muted);
}

.split {
  display: grid;
  grid-template-columns: minmax(280px, 0.92fr) minmax(320px, 1.08fr);
  gap: clamp(32px, 5vw, 80px);
  align-items: start;
  background: var(--white);
}

.tech-panel {
  border-top: 1px solid var(--line);
}

.tech-line {
  display: grid;
  grid-template-columns: 118px 1fr;
  gap: 22px;
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.tech-line span {
  color: var(--green);
  font-weight: 800;
}

.tech-line strong {
  font-size: 18px;
  line-height: 1.45;
}

.research {
  background: linear-gradient(180deg, var(--paper), #eef4f5);
}

.research-layout {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr 0.85fr;
  gap: 18px;
}

.feature-card {
  padding: 28px;
}

.feature-card:first-child {
  color: var(--white);
  background: var(--ink);
  box-shadow: var(--shadow);
}

.feature-card:first-child p {
  color: rgba(255, 255, 255, 0.76);
}

.tag {
  color: var(--amber);
  font-size: 13px;
  font-weight: 800;
}

.news-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.news-list article {
  padding: 24px;
}

.news-list time {
  display: block;
  margin-bottom: 18px;
  color: var(--green);
  font-weight: 800;
}

.contact {
  color: var(--white);
  background:
    linear-gradient(120deg, rgba(8, 19, 29, 0.96), rgba(20, 55, 62, 0.9)),
    var(--deep);
}

.contact-content {
  display: grid;
  grid-template-columns: minmax(280px, 1fr) minmax(260px, 420px);
  gap: clamp(28px, 6vw, 76px);
  align-items: start;
}

.contact p {
  color: rgba(255, 255, 255, 0.72);
}

address {
  display: grid;
  gap: 14px;
  padding: 28px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.06);
  font-style: normal;
}

address span:first-child {
  color: var(--cyan);
  font-weight: 800;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 28px;
  justify-content: space-between;
  padding: 24px clamp(20px, 6vw, 76px);
  color: #75828b;
  background: #06101a;
  font-size: 14px;
}

.site-footer a:hover {
  color: var(--white);
}

@media (max-width: 900px) {
  .site-header {
    height: 68px;
  }

  .site-nav {
    position: fixed;
    top: 68px;
    right: 14px;
    left: 14px;
    display: none;
    padding: 16px;
    border-radius: 8px;
    color: var(--ink);
    background: var(--white);
    box-shadow: var(--shadow);
  }

  .site-nav.is-open {
    display: grid;
    gap: 4px;
  }

  .site-nav a {
    padding: 12px 10px;
  }

  .nav-toggle {
    display: inline-block;
  }

  .hero {
    min-height: 780px;
  }

  .hero-image {
    object-position: 58% center;
  }

  .hero-content {
    width: auto;
    padding: 150px 20px 280px;
  }

  .hero-metrics,
  .intro-grid,
  .split,
  .research-layout,
  .news-list,
  .contact-content {
    grid-template-columns: 1fr;
  }

  .hero-metrics {
    right: 20px;
    left: 20px;
  }

  .hero-metrics div {
    min-height: auto;
    border-right: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  }

  .hero-metrics div:last-child {
    border-bottom: 0;
  }
}

@media (max-width: 560px) {
  h1 {
    font-size: 34px;
  }

  .brand {
    min-width: 0;
  }

  .brand small {
    display: none;
  }

  .hero {
    min-height: 880px;
  }

  .button {
    min-width: 136px;
    padding: 0 18px;
  }

  .tech-line {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .intro-grid article {
    min-height: auto;
  }
}