:root {
  --paper: #f4ead5;
  --paper-soft: #efe3ca;
  --paper-deep: #dfcfac;
  --ink: #161210;
  --ink-soft: #4e4337;
  --border: rgba(107, 84, 58, 0.42);
  --border-strong: rgba(107, 84, 58, 0.68);
  --stamp: #b1442c;
  --stamp-soft: rgba(177, 68, 44, 0.16);
  --signal: #2a6df5;
  --signal-soft: rgba(42, 109, 245, 0.12);
  --shadow: rgba(28, 20, 14, 0.14);
  --max-width: 1240px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(255, 255, 255, 0.5), transparent 32%),
    radial-gradient(circle at bottom right, rgba(107, 84, 58, 0.08), transparent 30%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.24), rgba(255, 255, 255, 0) 220px),
    linear-gradient(135deg, rgba(42, 109, 245, 0.03), transparent 28%),
    linear-gradient(180deg, #f8efdc 0%, var(--paper) 42%, #efe0be 100%);
  font-family: Georgia, "Times New Roman", "Songti SC", "Noto Serif SC", serif;
  line-height: 1.55;
}

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

img {
  max-width: 100%;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.page-shell {
  width: min(100%, calc(var(--max-width) + 64px));
  margin: 0 auto;
  padding: 24px 32px 48px;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 0 18px;
  backdrop-filter: blur(10px);
  background: linear-gradient(180deg, rgba(244, 234, 213, 0.92), rgba(244, 234, 213, 0.74));
  border-bottom: 1px solid rgba(107, 84, 58, 0.18);
}

.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.brand-lockup__mark {
  flex: 0 0 56px;
  width: 56px;
  height: 56px;
  background: url("site-mark-seal.png") center/contain no-repeat;
  filter: drop-shadow(0 4px 8px rgba(57, 31, 24, 0.18));
  opacity: 0.96;
}

.brand-lockup__text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.brand-lockup__cn {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.brand-lockup__en {
  font-size: 0.77rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.topbar__controls {
  display: flex;
  align-items: center;
  gap: 18px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 18px;
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.site-nav a,
.lang-switch a,
.footer__links a {
  transition: color 150ms ease;
}

.site-nav a:hover,
.site-nav a:focus-visible,
.lang-switch a:hover,
.lang-switch a:focus-visible,
.footer__links a:hover,
.footer__links a:focus-visible {
  color: var(--stamp);
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.lang-switch a[aria-current="page"],
.mobile-menu__lang a[aria-current="page"] {
  color: var(--stamp);
}

.menu-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: rgba(244, 234, 213, 0.76);
  cursor: pointer;
}

.menu-toggle span:not(.sr-only) {
  display: block;
  width: 18px;
  height: 1px;
  margin: 4px auto;
  background: var(--ink);
}

.mobile-menu {
  display: none;
  position: sticky;
  top: 78px;
  z-index: 18;
  margin-bottom: 16px;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: 18px;
  background: rgba(250, 242, 225, 0.96);
  box-shadow: 0 18px 36px var(--shadow);
}

.mobile-menu a {
  display: block;
  padding: 12px 0;
  border-bottom: 1px solid rgba(107, 84, 58, 0.12);
}

.mobile-menu a:last-child {
  border-bottom: 0;
}

.mobile-menu__lang {
  display: flex;
  gap: 14px;
  margin-top: 10px;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.section {
  padding: 42px 0;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(320px, 0.9fr);
  align-items: center;
  gap: 44px;
  min-height: 78vh;
  padding-top: 32px;
}

.eyebrow,
.section-heading__eyebrow,
.feature-card__tag,
.library-card__kind,
.works-card__label {
  font-family: "Courier New", "JetBrains Mono", monospace;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.eyebrow {
  margin: 0 0 18px;
  font-size: 0.78rem;
  color: var(--stamp);
}

.hero h1 {
  margin: 0;
  max-width: 14ch;
  font-size: clamp(2.5rem, 5.3vw, 5.4rem);
  line-height: 0.98;
  letter-spacing: -0.04em;
}

.hero__lede {
  margin: 22px 0 0;
  max-width: 30rem;
  font-size: clamp(1.02rem, 1.5vw, 1.22rem);
  color: var(--ink-soft);
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 28px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: 0.92rem;
  font-weight: 600;
}

.button--primary {
  color: #fffaf3;
  background: linear-gradient(135deg, var(--ink), #30251c);
  box-shadow: 0 12px 24px rgba(22, 18, 16, 0.18);
}

.button--secondary {
  border-color: var(--border-strong);
  background: rgba(255, 255, 255, 0.22);
}

.hero__meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin: 32px 0 0;
  padding: 0;
}

.hero__meta div {
  padding: 14px 16px;
  border: 1px solid rgba(107, 84, 58, 0.18);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.18);
}

.hero__meta dt {
  margin: 0 0 4px;
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.hero__meta dd {
  margin: 0;
  font-size: 0.95rem;
}

.hero__visual {
  position: relative;
}

.hero-specimen {
  position: relative;
  display: flex;
  justify-content: center;
  padding: 8px 0 0 28px;
}

.hero-specimen__composite {
  display: block;
  width: min(100%, 520px);
  height: auto;
  filter: drop-shadow(0 22px 30px rgba(28, 20, 14, 0.08));
}

.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 22px;
}

.section-heading h2 {
  margin: 8px 0 0;
  max-width: 16ch;
  font-size: clamp(1.7rem, 3vw, 3rem);
  line-height: 1.06;
  letter-spacing: -0.03em;
}

.section-heading__eyebrow {
  margin: 0;
  font-size: 0.76rem;
  color: var(--stamp);
}

.section-heading__note {
  margin: 0;
  max-width: 26rem;
  font-size: 0.98rem;
  color: var(--ink-soft);
}

.feature-grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr 1fr;
  gap: 18px;
}

.feature-card,
.strip-card,
.library-card,
.institute-card {
  position: relative;
  padding: 24px;
  border: 1px solid rgba(107, 84, 58, 0.2);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.18);
  box-shadow: 0 14px 26px rgba(28, 20, 14, 0.05);
}

.feature-card--lead {
  background:
    linear-gradient(135deg, rgba(42, 109, 245, 0.08), transparent 58%),
    rgba(255, 255, 255, 0.2);
}

.feature-card__tag,
.library-card__kind,
.works-card__label {
  margin: 0;
  font-size: 0.73rem;
  color: var(--stamp);
}

.feature-card h3,
.strip-card h3,
.library-card h3,
.works-card h3,
.institute-card h3 {
  margin: 12px 0 10px;
  font-size: 1.38rem;
  line-height: 1.14;
}

.feature-card p,
.strip-card p,
.library-card p,
.works-card p,
.institute-card p,
.footer__note {
  margin: 0;
  color: var(--ink-soft);
}

.feature-card__state {
  display: inline-flex;
  margin-top: 18px;
  padding: 7px 12px;
  border-radius: 999px;
  border: 1px solid rgba(177, 68, 44, 0.22);
  background: var(--stamp-soft);
  font-size: 0.78rem;
  color: var(--stamp);
}

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

.strip-card {
  min-height: 232px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.18), rgba(255, 255, 255, 0.08)),
    rgba(255, 255, 255, 0.18);
}

.strip-card__index {
  display: inline-flex;
  margin-bottom: 18px;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(42, 109, 245, 0.09);
  color: var(--signal);
  font-family: "Courier New", monospace;
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

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

.works-card {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 24px;
  align-items: stretch;
  padding: 28px;
  border: 1px solid rgba(107, 84, 58, 0.22);
  border-radius: 28px;
  background:
    linear-gradient(135deg, rgba(22, 18, 16, 0.92), rgba(40, 32, 25, 0.84)),
    rgba(22, 18, 16, 0.92);
  color: #f5ecdd;
}

.works-card p,
.works-card .works-card__label {
  color: rgba(245, 236, 221, 0.78);
}

.works-card__content h3 {
  color: #fff8ef;
}

.works-card__status {
  display: grid;
  gap: 12px;
  align-content: start;
}

.works-card__status span {
  display: inline-flex;
  align-items: center;
  min-height: 56px;
  padding: 0 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.92rem;
}

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

.footer {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  padding: 34px 0 18px;
  border-top: 1px solid rgba(107, 84, 58, 0.18);
}

.footer__brand {
  margin: 0 0 8px;
  font-weight: 700;
}

.footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.92rem;
}

@media (max-width: 1279px) {
  .hero {
    grid-template-columns: 1fr;
    gap: 28px;
    min-height: auto;
    padding-top: 20px;
  }

  .hero h1,
  .section-heading h2 {
    max-width: none;
  }

  .feature-grid,
  .library-grid,
  .institute-grid,
  .strip-grid,
  .works-card {
    grid-template-columns: 1fr;
  }

  .section-heading,
  .footer {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 767px) {
  .page-shell {
    padding: 16px 18px 36px;
  }

  .topbar {
    gap: 16px;
    padding: 12px 0 16px;
  }

  .site-nav,
  .lang-switch {
    display: none;
  }

  .menu-toggle,
  .mobile-menu.is-open {
    display: block;
  }

  .brand-lockup__mark {
    width: 46px;
    height: 46px;
  }

  .brand-lockup__cn {
    font-size: 1.02rem;
  }

  .brand-lockup__en {
    font-size: 0.64rem;
    letter-spacing: 0.1em;
  }

  .section {
    padding: 28px 0;
  }

  .hero {
    min-height: auto;
    padding-top: 8px;
  }

  .hero h1 {
    font-size: clamp(2rem, 11vw, 3.1rem);
  }

  .hero__actions,
  .hero__meta {
    grid-template-columns: 1fr;
  }

  .hero__actions {
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .hero-specimen {
    padding: 8px 0 0;
  }

  .hero-specimen {
    padding: 0;
  }

  .hero-specimen__composite {
    width: min(100%, 340px);
  }

  .feature-card,
  .strip-card,
  .library-card,
  .institute-card,
  .works-card {
    padding: 20px;
    border-radius: 20px;
  }

  .section-heading__note {
    font-size: 0.94rem;
  }
}