:root {
  --ink: #202020;
  --muted: #5e6470;
  --line: #dedede;
  --paper: #ffffff;
  --soft: #f7f7f5;
  --accent: #7a1f2b;
  --accent-dark: #5e1721;
  --teal: #2b655f;
  --gold: #9a742a;
  --shadow: 0 12px 28px rgba(32, 32, 32, 0.08);
  --font-serif: "Times New Roman", "SimSun", "Songti SC", "Noto Serif CJK SC", serif;
  --max: 980px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-serif);
  font-size: 16px;
  line-height: 1.58;
  text-rendering: optimizeLegibility;
}

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

img {
  display: block;
  max-width: 100%;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 24px;
  padding: 12px clamp(18px, 4vw, 44px);
  border-bottom: 1px solid rgba(222, 222, 222, 0.9);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
}

.brand-mark {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border: 1px solid var(--ink);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-serif);
  font-size: 14px;
}

.brand-text {
  white-space: nowrap;
}

.site-nav {
  display: flex;
  justify-content: center;
  gap: 22px;
  color: var(--muted);
  font-size: 15px;
}

.site-nav a {
  padding: 6px 0;
}

.site-nav a:hover {
  color: var(--accent);
}

.language-switch {
  display: inline-flex;
  gap: 2px;
  padding: 2px;
  border: 1px solid var(--line);
  background: var(--paper);
}

.language-button,
.nav-toggle {
  border: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  cursor: pointer;
}

.language-button {
  min-width: 34px;
  min-height: 28px;
  padding: 2px 7px;
  font-size: 13px;
}

.language-button.is-active {
  background: var(--soft);
  color: var(--accent);
}

.nav-toggle {
  display: none;
  width: 38px;
  height: 38px;
  align-items: center;
  justify-content: center;
  gap: 6px;
  flex-direction: column;
  border: 1px solid var(--line);
}

.nav-toggle span {
  width: 18px;
  height: 2px;
  background: var(--ink);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(230px, 0.42fr);
  gap: clamp(30px, 6vw, 64px);
  align-items: center;
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(34px, 5vw, 56px) clamp(18px, 4vw, 44px) 38px;
}

.eyebrow,
.section-kicker,
.paper-year {
  margin: 0;
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1 {
  margin: 9px 0 2px;
  font-family: var(--font-serif);
  font-size: clamp(44px, 7vw, 68px);
  font-weight: 500;
  line-height: 1;
}

.role {
  margin: 0;
  color: var(--teal);
  font-size: clamp(19px, 2.4vw, 24px);
  font-weight: 600;
}

.hero-summary {
  max-width: 650px;
  margin: 20px 0 0;
  color: #333a42;
  font-size: clamp(17px, 2vw, 19px);
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 36px;
  padding: 6px 14px;
  border: 1px solid var(--ink);
  font-size: 15px;
  font-weight: 600;
}

.button.primary {
  background: var(--ink);
  color: #fff;
}

.button.secondary {
  background: transparent;
  color: var(--ink);
}

.portrait-block {
  margin: 0;
  justify-self: end;
  width: min(100%, 260px);
}

.portrait-block img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  object-position: center top;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.portrait-block figcaption {
  margin-top: 10px;
  padding-left: 10px;
  border-left: 2px solid var(--gold);
  color: var(--muted);
  font-size: 14px;
}

.section {
  max-width: var(--max);
  margin: 0 auto;
  padding: 46px clamp(18px, 4vw, 44px);
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(130px, 0.28fr) minmax(0, 1fr);
  gap: 26px;
  align-items: end;
  margin-bottom: 22px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 10px;
}

.section-heading h2,
.contact-section h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: clamp(25px, 3vw, 34px);
  font-weight: 500;
  line-height: 1.1;
}

.intro-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(300px, 0.64fr);
  gap: clamp(28px, 5vw, 58px);
  border-top: 1px solid var(--line);
}

.profile-note h2 {
  margin: 0 0 14px;
  font-size: 28px;
  line-height: 1.2;
}

.profile-note p {
  margin: 0;
  color: #38404a;
  font-size: 18px;
}

.facts {
  display: grid;
  gap: 18px;
  margin: 0;
}

.facts div {
  border-left: 3px solid var(--teal);
  padding-left: 16px;
}

.facts dt {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
}

.facts dd {
  margin: 4px 0 0;
  font-weight: 650;
}

.research-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.research-item {
  display: grid;
  grid-template-columns: 70px minmax(0, 1fr);
  gap: 26px;
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
}

.item-index {
  color: var(--gold);
  font-family: Georgia, serif;
  font-size: 26px;
}

.research-item h3,
.paper h3,
.working-list h3,
.timeline h3 {
  margin: 0;
  font-size: 18px;
  line-height: 1.35;
  font-weight: 600;
}

.research-item p,
.paper p,
.working-list p,
.timeline p {
  margin: 8px 0 0;
  color: var(--muted);
}

.paper-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.paper {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: 0 18px;
  min-height: 0;
  padding: 15px 0;
  border: 0;
  border-bottom: 1px solid var(--line);
  background: var(--paper);
}

.paper h3 {
  grid-column: 2;
}

.paper p:not(.paper-year) {
  grid-column: 2;
}

.paper-year {
  grid-row: 1 / span 3;
  padding-top: 2px;
}

.working-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.working-list article {
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.teaching-groups {
  display: grid;
  gap: 18px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.teaching-group {
  display: grid;
  gap: 7px;
}

.teaching-group h3 {
  margin: 0;
  color: var(--ink);
  font-size: 17px;
  font-weight: 600;
  line-height: 1.35;
}

.course-list {
  display: grid;
  gap: 4px;
  margin: 0;
  padding-left: 18px;
  color: #333a42;
  font-size: 16.5px;
}

.course-list li {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 20px;
  align-items: baseline;
}

.course-list li::before {
  content: "•";
  position: absolute;
  left: -15px;
  color: var(--ink);
}

.course-list time {
  color: var(--muted);
  font-weight: 650;
  white-space: nowrap;
}

.education-section {
  border-top: 1px solid var(--line);
}

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

.timeline article {
  display: grid;
  grid-template-columns: 118px minmax(0, 1fr);
  gap: 22px;
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}

.timeline time {
  color: var(--accent);
  font-weight: 700;
}

.contact-section {
  display: grid;
  grid-template-columns: minmax(130px, 0.28fr) minmax(0, 1fr);
  gap: 26px;
  max-width: var(--max);
  margin: 0 auto;
  padding: 46px clamp(18px, 4vw, 44px) 58px;
  border-top: 1px solid var(--line);
}

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  align-items: center;
  color: var(--muted);
  font-size: 17px;
}

.contact-links a {
  color: var(--accent);
  font-weight: 700;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 16px clamp(18px, 4vw, 44px);
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 860px) {
  .site-header {
    grid-template-columns: auto auto auto;
    gap: 12px;
  }

  .nav-toggle {
    display: inline-flex;
    justify-self: end;
  }

  .site-nav {
    position: absolute;
    top: 71px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    gap: 0;
    padding: 10px 20px 18px;
    border-bottom: 1px solid var(--line);
    background: #fff;
  }

  .site-nav.is-open {
    display: flex;
  }

  .site-nav a {
    padding: 10px 0;
  }

  .hero,
  .intro-grid,
  .contact-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    padding-top: 34px;
    gap: 24px;
  }

  .portrait-block {
    justify-self: start;
    width: min(100%, 250px);
  }

  .section-heading {
    grid-template-columns: 1fr;
    gap: 8px;
  }

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

  .paper {
    grid-template-columns: 64px minmax(0, 1fr);
  }
}

@media (max-width: 560px) {
  .brand-text {
    display: none;
  }

  .hero h1 {
    font-size: 40px;
  }

  .hero-actions {
    align-items: center;
    flex-direction: row;
  }

  .button {
    min-height: 34px;
    padding: 5px 12px;
  }

  .portrait-block {
    width: min(100%, 205px);
  }

  .timeline article {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .course-list li {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 12px;
  }

  .section {
    padding-top: 38px;
    padding-bottom: 38px;
  }

  .site-footer {
    flex-direction: column;
  }
}

@media print {
  .site-header,
  .language-switch,
  .nav-toggle {
    display: none;
  }

  body {
    color: #000;
  }

  .hero {
    min-height: auto;
  }

  .paper {
    break-inside: avoid;
  }
}

body:not(.lang-en) [data-lang="en"] {
  display: none !important;
}

body.lang-en [data-lang="zh"] {
  display: none !important;
}

body.lang-en [data-lang="en"] {
  display: revert;
}