:root {
  --ink: #14243a;
  --muted: #66758a;
  --blue: #164d87;
  --blue-deep: #0c315d;
  --pale: #edf5fc;
  --line: #dce6f1;
  --white: #fff;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

.site-header {
  position: sticky;
  z-index: 10;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  padding: 0 max(28px, calc((100vw - 1160px) / 2));
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand strong {
  color: var(--blue);
  font-size: 28px;
  letter-spacing: -1px;
}

.brand span {
  padding-left: 12px;
  color: #35445a;
  border-left: 1px solid var(--line);
  font-size: 14px;
}

nav {
  display: flex;
  gap: 34px;
}

nav a {
  color: #425066;
  font-size: 14px;
  text-decoration: none;
}

nav a:hover {
  color: var(--blue);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(340px, 0.75fr);
  min-height: 520px;
  background: linear-gradient(125deg, #f9fcff 0 62%, #eaf4fd 62% 100%);
}

.hero-copy {
  align-self: center;
  width: min(750px, calc(100% - 56px));
  margin-left: max(28px, calc((100vw - 1160px) / 2));
  padding: 78px 0;
}

.eyebrow,
.section-title > span,
.contact-label {
  display: block;
  margin: 0 0 16px;
  color: var(--blue);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.2em;
}

h1 {
  margin: 0;
  font-size: clamp(42px, 5.8vw, 72px);
  line-height: 1.12;
  letter-spacing: -0.045em;
}

.english-name {
  margin: 14px 0 0;
  color: var(--blue);
  font-size: clamp(18px, 2.2vw, 28px);
  letter-spacing: 0.04em;
  line-height: 1.4;
}

.hero-intro {
  max-width: 620px;
  margin: 32px 0;
  color: #526278;
  font-size: 18px;
  line-height: 1.9;
}

.primary-link {
  display: inline-block;
  padding: 13px 24px;
  color: var(--white);
  background: var(--blue);
  border-radius: 4px;
  font-size: 14px;
  text-decoration: none;
}

.hero-mark {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 16px;
  overflow: hidden;
  padding: 50px 32px;
  color: rgba(22, 77, 135, 0.2);
  font-size: clamp(34px, 4.6vw, 72px);
  font-weight: 800;
  letter-spacing: -0.05em;
  line-height: 0.95;
}

.section {
  width: min(1160px, calc(100% - 56px));
  margin: 0 auto;
  padding: 96px 0;
}

.section-title h2,
.contact h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 44px);
  letter-spacing: -0.04em;
}

.about {
  display: grid;
  grid-template-columns: 0.7fr 1.3fr;
  gap: 80px;
  align-items: start;
}

.about-copy {
  padding-left: 34px;
  border-left: 3px solid var(--blue);
}

.about-copy p {
  margin: 0 0 22px;
  color: #56657a;
  font-size: 17px;
  line-height: 2;
}

.research {
  width: 100%;
  padding-right: max(28px, calc((100vw - 1160px) / 2));
  padding-left: max(28px, calc((100vw - 1160px) / 2));
  background: #f6f9fc;
}

.research-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 46px;
}

.research-grid article {
  min-height: 230px;
  padding: 30px;
  background: var(--white);
  border: 1px solid var(--line);
}

.research-grid b {
  color: #87a9cc;
  font-size: 13px;
}

.research-grid h3 {
  margin: 46px 0 14px;
  font-size: 20px;
}

.research-grid p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.8;
}

.team-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
  margin-top: 46px;
}

.team-grid article {
  display: grid;
  grid-template-columns: 82px 1fr;
  gap: 24px;
  padding: 34px;
  border: 1px solid var(--line);
  border-radius: 8px;
}

.avatar {
  display: grid;
  width: 82px;
  height: 82px;
  place-items: center;
  color: var(--white);
  background: linear-gradient(145deg, var(--blue), #2a78c1);
  border-radius: 50%;
  font-size: 26px;
}

.team-grid h3 {
  margin: 0 0 8px;
  font-size: 24px;
}

.team-grid p {
  margin: 8px 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.75;
}

.team-grid .role {
  color: var(--blue);
}

.team-grid a {
  display: inline-block;
  margin-top: 10px;
  color: var(--blue);
  font-size: 13px;
}

.activities {
  padding-top: 30px;
}

.activity-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  margin-top: 42px;
  padding: 36px 42px;
  color: var(--white);
  background: linear-gradient(120deg, var(--blue-deep), var(--blue));
  border-radius: 8px;
  text-decoration: none;
}

.activity-card span,
.activity-card p {
  color: #bed9f2;
  font-size: 13px;
}

.activity-card h3 {
  margin: 10px 0 8px;
  font-size: 26px;
}

.activity-card p {
  margin: 0;
}

.activity-card > strong {
  white-space: nowrap;
  font-size: 14px;
}

.contact {
  display: flex;
  align-items: end;
  justify-content: space-between;
  margin-bottom: 90px;
  padding: 58px 64px;
  color: var(--white);
  background: var(--blue-deep);
  border-radius: 8px;
}

.contact-label {
  color: #98c8f1;
}

address {
  display: flex;
  flex-direction: column;
  gap: 9px;
  color: #d9e7f5;
  font-size: 14px;
  font-style: normal;
  text-align: right;
}

address strong {
  color: var(--white);
  font-size: 17px;
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 34px max(28px, calc((100vw - 1160px) / 2));
  color: #78869a;
  border-top: 1px solid var(--line);
  font-size: 12px;
}

footer p {
  margin: 0;
}

@media (max-width: 900px) {
  nav {
    display: none;
  }

  .hero {
    grid-template-columns: 1fr;
    min-height: 0;
    background: linear-gradient(145deg, #f9fcff, #e9f4fd);
  }

  .hero-copy {
    width: calc(100% - 40px);
    margin-left: 20px;
    padding: 72px 0 62px;
  }

  .hero-mark {
    display: none;
  }

  .about {
    grid-template-columns: 1fr;
    gap: 38px;
  }

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

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

@media (max-width: 600px) {
  .site-header {
    min-height: 64px;
    padding: 0 18px;
  }

  .brand strong {
    font-size: 24px;
  }

  .section {
    width: calc(100% - 36px);
    padding: 68px 0;
  }

  .hero-copy {
    padding: 58px 0 54px;
  }

  h1 {
    font-size: 38px;
  }

  .hero-intro {
    margin: 26px 0;
    font-size: 16px;
  }

  .about-copy {
    padding-left: 20px;
  }

  .about-copy p {
    font-size: 15px;
  }

  .research {
    width: 100%;
    padding-right: 18px;
    padding-left: 18px;
  }

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

  .research-grid article {
    min-height: 190px;
  }

  .team-grid article {
    grid-template-columns: 58px 1fr;
    gap: 18px;
    padding: 24px 20px;
  }

  .avatar {
    width: 58px;
    height: 58px;
    font-size: 20px;
  }

  .contact {
    display: block;
    width: calc(100% - 36px);
    margin-bottom: 54px;
    padding: 36px 26px;
  }

  .activity-card {
    display: block;
    padding: 28px 24px;
  }

  .activity-card > strong {
    display: inline-block;
    margin-top: 24px;
  }

  address {
    margin-top: 32px;
    text-align: left;
  }

  footer {
    display: block;
    padding: 28px 18px;
  }

  footer p {
    margin-top: 10px;
  }
}