:root {
  --page-width: 1120px;
  --text: #262626;
  --muted: #70757a;
  --line: #e1e5ea;
  --blue: #1a73e8;
  --blue-dark: #0b3d91;
  --paper: #ffffff;
  --soft: #f7f9fc;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 16px;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
}

.wrap,
.header-inner {
  width: min(var(--page-width), calc(100% - 64px));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.97);
  border-bottom: 1px solid rgba(32, 33, 36, 0.12);
  backdrop-filter: blur(10px);
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 36px;
}

.brand {
  flex: 0 0 auto;
  color: #202124;
  text-decoration: none;
  font-size: 22px;
  font-weight: 500;
  letter-spacing: 0.01em;
}

.site-nav {
  display: flex;
  align-items: stretch;
  gap: 30px;
  min-height: 72px;
}

.site-nav a {
  display: flex;
  align-items: center;
  color: #3c4043;
  text-decoration: none;
  border-bottom: 3px solid transparent;
  padding: 3px 0 0;
  font-size: 14px;
  white-space: nowrap;
  transition: color .16s ease, border-color .16s ease;
}

.site-nav a:hover,
.site-nav a:focus-visible,
.site-nav a.active {
  color: var(--blue);
  border-bottom-color: var(--blue);
}

.hero {
  position: relative;
  min-height: 390px;
  display: grid;
  align-items: end;
  overflow: hidden;
  background:
    linear-gradient(90deg, rgba(7, 40, 84, .64), rgba(7, 40, 84, .12) 64%, rgba(7, 40, 84, .05)),
    url("assets/OIST.jpg") center 42% / cover no-repeat;
  border-bottom: 1px solid rgba(0,0,0,.06);
}

.hero-shade {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(0,0,0,.02) 0%, rgba(0,0,0,.05) 38%, rgba(0,0,0,.30) 100%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 1;
  padding-block: 74px 54px;
  color: #fff;
}

.eyebrow {
  margin: 0 0 10px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: .04em;
  text-transform: uppercase;
}

.hero h1 {
  margin: 0;
  font-size: clamp(52px, 7vw, 82px);
  line-height: .98;
  font-weight: 500;
  letter-spacing: -.025em;
  text-shadow: 0 2px 15px rgba(0,0,0,.18);
}

.subtitle {
  max-width: 780px;
  margin: 18px 0 0;
  font-size: clamp(20px, 2.8vw, 30px);
  line-height: 1.28;
  font-weight: 400;
  text-shadow: 0 2px 14px rgba(0,0,0,.16);
}

.page-content {
  padding-block: 58px 76px;
}

.intro-grid,
.content-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 72px;
}

.info-card {
  padding: 0;
}

.kicker {
  margin: 0 0 8px;
  color: var(--blue);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.info-card h2 {
  margin: 0;
  font-size: 22px;
  line-height: 1.4;
  font-weight: 400;
}

.section-rule {
  height: 1px;
  background: var(--line);
  margin: 46px 0;
}

.section {
  scroll-margin-top: 96px;
}

.section h2 {
  position: relative;
  margin: 0 0 14px;
  padding-left: 17px;
  color: #202124;
  font-size: 22px;
  line-height: 1.35;
  font-weight: 500;
}

.section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: .26em;
  width: 4px;
  height: 1.05em;
  border-radius: 2px;
  background: var(--blue);
}

.section p { margin: 0; }
.section-note {
  margin: -7px 0 12px !important;
  color: var(--muted);
  font-size: 14px;
}

.clean-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.clean-list li {
  margin: 8px 0;
}

.clean-list li::before {
  content: "•";
  color: #5f6368;
  margin-right: 10px;
}

.clean-list span {
  color: #5f6368;
}

.muted { color: var(--muted); }

.history-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 30px;
}

.history-heading h2 { margin-bottom: 5px; }

.history-links {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  margin-top: 22px;
}

.history-links a {
  color: #174ea6;
  text-decoration: none;
  text-align: center;
  padding: 20px 12px;
  border-right: 1px solid var(--line);
  font-size: 14px;
  font-weight: 500;
}

.history-links a:last-child { border-right: 0; }
.history-links a:hover { background: var(--soft); color: var(--blue); }

.updated {
  margin: 54px 0 0;
  color: var(--muted);
  font-size: 13px;
  text-align: right;
}

.site-footer {
  background: #f8f9fa;
  border-top: 1px solid var(--line);
  color: #5f6368;
  font-size: 13px;
}

.footer-inner {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

@media (max-width: 900px) {
  .site-nav { gap: 18px; }
  .site-nav a { font-size: 13px; }
  .intro-grid,
  .content-grid { gap: 42px; }
  .history-links { grid-template-columns: repeat(3, 1fr); }
  .history-links a:nth-child(3) { border-right: 0; }
  .history-links a:nth-child(-n+3) { border-bottom: 1px solid var(--line); }
}

@media (max-width: 720px) {
  .wrap,
  .header-inner { width: min(var(--page-width), calc(100% - 34px)); }
  .site-header { position: static; }
  .header-inner {
    min-height: auto;
    padding-block: 16px;
    display: block;
  }
  .site-nav {
    min-height: 0;
    margin-top: 13px;
    gap: 18px;
    overflow-x: auto;
    padding-bottom: 2px;
  }
  .site-nav a { min-height: 38px; }
  .hero { min-height: 335px; }
  .hero-inner { padding-block: 54px 38px; }
  .intro-grid,
  .content-grid { grid-template-columns: 1fr; gap: 34px; }
  .section-rule { margin: 38px 0; }
  .history-links { grid-template-columns: repeat(2, 1fr); }
  .history-links a,
  .history-links a:nth-child(3) { border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
  .history-links a:nth-child(2n) { border-right: 0; }
  .history-links a:nth-last-child(-n+2) { border-bottom: 0; }
  .updated { text-align: left; }
  .footer-inner { display: block; padding-block: 20px; }
  .footer-inner span { display: block; }
}