/* Colors and typefaces */
:root {
  --ink: #172b46;
  --muted: #566477;
  --blue: #214fc1;
  --line: #dce3ee;
  --paper: #fff;
  --wash: #f2f5fa;
  --serif: Georgia,'Times New Roman','Noto Serif SC',serif;
  --sans: Inter,-apple-system,BlinkMacSystemFont,'Segoe UI',Arial,sans-serif;
}

/* Base elements and accessible focus styles */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 7rem;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--blue);
  text-underline-offset: .22em;
}

a:hover {
  text-decoration-thickness: 2px;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 5px;
}

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

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

h1,
h2,
h3 {
  line-height: 1.2;
}

h1,
h2 {
  font-family: var(--serif);
  font-weight: 400;
}

h1 {
  font-size: clamp(2.7rem,5vw,4.6rem);
  letter-spacing: -.035em;
}

h2 {
  font-size: clamp(1.9rem,3vw,2.6rem);
  letter-spacing: -.02em;
}

h3 {
  font-size: 1.2rem;
  line-height: 1.5;
  font-weight: 600;
}

p+p {
  margin-top: 1rem;
}

.container {
  width: min(1140px,calc(100% - 6rem));
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -5rem;
  background: var(--ink);
  color: white;
  padding: .5rem 1rem;
  z-index: 20;
}

.skip-link:focus {
  top: 1rem;
}

/* Header and primary navigation */
.site-header {
  border-top: 4px solid var(--blue);
  border-bottom: 1px solid var(--line);
  background: white;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 92px;
  gap: 2rem;
}

.brand {
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.5rem;
  text-decoration: none;
  white-space: nowrap;
}

.brand span {
  font-size: 1rem;
  color: var(--muted);
  margin-left: .65rem;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 1.65rem;
}

.main-nav>a {
  color: var(--muted);
  text-decoration: none;
  font-size: .94rem;
  padding: 1.8rem 0;
}

.main-nav [aria-current=page],
.main-nav [data-active=true] {
  color: var(--blue);
}

.menu-toggle {
  display: none;
}

/* Home introduction and small portrait */
.eyebrow {
  text-transform: uppercase;
  letter-spacing: .14em;
  font-size: .78rem;
  color: var(--blue);
  font-weight: 600;
  margin-bottom: 1.1rem;
}

.home-intro {
  display: grid;
  grid-template-columns: minmax(0,1fr) 180px;
  gap: 3rem;
  padding: 5rem 0 4rem;
  align-items: center;
}

.name-chinese {
  font-size: 1.65rem;
  letter-spacing: .12em;
  color: var(--muted);
  margin-left: .7rem;
  white-space: nowrap;
}

.position {
  font-size: 1.12rem;
  margin-top: 1.1rem;
  color: var(--ink);
}

.affiliation {
  color: var(--muted);
  font-size: 1rem;
  margin-top: .2rem;
}

.intro-description {
  margin-top: 1.8rem;
  max-width: 580px;
  font-size: 1.11rem;
  line-height: 1.9;
}

.inline-links {
  display: flex;
  gap: 1.4rem;
  flex-wrap: wrap;
  margin-top: 1.65rem;
  font-size: .94rem;
}

.inline-links a {
  text-decoration: none;
  border-bottom: 1px solid #214fc140;
}

.portrait {
  margin: 0;
  width: 180px;
  max-width: 100%;
}

.portrait img {
  width: 100%;
  height: auto;
  aspect-ratio: 860 / 959;
  object-fit: cover;
  object-position: center 44%;
}

.portrait figcaption {
  font-size: .78rem;
  color: var(--muted);
  margin-top: .65rem;
}

.portrait figcaption a {
  color: inherit;
}

/* Research cards and publication entries */
.content-section {
  padding: 3.5rem 0;
  border-top: 1px solid var(--line);
}

.section-heading {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1.5rem;
  margin-bottom: 1.9rem;
}

.section-heading>a {
  font-size: .9rem;
  white-space: nowrap;
}

.research-grid {
  display: grid;
  grid-template-columns: repeat(3,1fr);
  gap: 2.6rem;
}

.research-item {
  border-top: 3px solid var(--blue);
  padding-top: 1.2rem;
}

.research-item h3 a {
  color: var(--ink);
  text-decoration: none;
}

.research-item h3 a:hover {
  color: var(--blue);
}

.research-item p {
  color: var(--muted);
  font-size: .98rem;
  margin-top: .75rem;
}

.research-item .index {
  color: var(--blue);
  font-size: .8rem;
  margin-bottom: 1rem;
}

.publication {
  padding: 1.7rem 0;
  border-top: 1px solid var(--line);
}

.publication:first-child {
  border-top: 0;
  padding-top: 0;
}

.publication h3 a {
  color: var(--ink);
  text-decoration: none;
}

.publication h3 a:hover {
  color: var(--blue);
}

.publication .authors {
  color: var(--muted);
  margin-top: .45rem;
  font-size: .96rem;
}

.publication .venue {
  font-size: .92rem;
  margin-top: .25rem;
}

.publication .paper-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: .6rem;
  font-size: .87rem;
}

.paper-links a {
  text-decoration: none;
}

.home-bottom {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 5rem;
}

.home-bottom h2 {
  font-size: 2rem;
  margin-bottom: 1.3rem;
}

.home-bottom p {
  color: var(--muted);
}

.contact-lines {
  font-style: normal;
  color: var(--muted);
}

/* Shared footer */
.site-footer {
  padding: 2rem 0;
  background: var(--wash);
  border-top: 1px solid var(--line);
  margin-top: 2.5rem;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 2rem;
  font-size: .85rem;
  color: var(--muted);
}

.footer-inner a {
  color: var(--muted);
}

/* Tablet layouts */
@media (max-width: 980px) {
  .container {
    width: calc(100% - 3rem);
  }

  .header-inner {
    gap: 1rem;
  }

  .main-nav {
    gap: 1.1rem;
  }

  .home-intro {
    gap: 2.5rem;
    padding-top: 3.5rem;
  }

  .name-chinese {
    display: block;
    margin: 1rem 0 0;
  }

  .research-grid {
    gap: 1.5rem;
  }

  .brand span {
    display: none;
  }

}

/* Mobile layouts */
@media (max-width: 700px) {
  .container {
    width: calc(100% - 2.5rem);
  }

  .header-inner {
    min-height: 76px;
    flex-wrap: wrap;
  }

  .brand {
    font-size: 1.45rem;
  }

  .menu-toggle {
    display: block;
    font: inherit;
    font-size: .9rem;
    background: transparent;
    border: 1px solid var(--line);
    border-radius: 3px;
    color: var(--ink);
    padding: .45rem .8rem;
  }

  .main-nav {
    width: 100%;
    display: flex;
    flex-wrap: wrap;
    gap: 0;
    align-items: flex-start;
    padding-bottom: 1rem;
  }

  .main-nav>a {
    width: 50%;
  }

  .main-nav>a {
    display: block;
    padding: .55rem 0;
  }

  .js .main-nav {
    display: none;
  }

  .js .main-nav.is-open {
    display: flex;
  }

  .home-intro {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 2.8rem 0;
  }

  .home-intro .portrait {
    max-width: 180px;
    width: 100%;
  }

  .name-chinese {
    display: inline-block;
    font-size: 1.3rem;
    margin-left: .5rem;
  }

  .intro-description {
    font-size: 1.05rem;
  }

  .research-grid,
  .home-bottom {
    grid-template-columns: 1fr;
    gap: 1.9rem;
  }

  /* Research cards and publication entries */
.content-section {
    padding: 2.5rem 0;
  }

  .section-heading {
    align-items: flex-start;
    flex-wrap: wrap;
    gap: .6rem;
  }

  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: .5rem;
  }

  .publication h3 {
    font-size: 1.1rem;
  }

}

/* Reduced motion preference */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

}

/* Interior pages and section navigation */
.page-heading {
  padding: 2.5rem 0 3.3rem;
  max-width: 960px;
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: .6rem;
  font-size: .85rem;
  color: var(--muted);
  margin-bottom: 2.4rem;
  line-height: 1.6;
}

.breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
}

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

.breadcrumbs [aria-current=page] {
  color: var(--ink);
}

.page-heading h1 {
  font-size: clamp(2.5rem,4.5vw,3.9rem);
}

.page-intro {
  margin-top: 1.3rem;
  font-size: 1.12rem;
  color: var(--muted);
  max-width: 780px;
  line-height: 1.85;
}

.prose {
  max-width: 800px;
}

.prose h2 {
  margin-bottom: 1.4rem;
}

.prose h3 {
  margin: 1.5rem 0 .65rem;
}

.prose p {
  color: var(--muted);
  font-size: 1.02rem;
  line-height: 1.9;
}

.reading-layout,
.publication-layout {
  display: grid;
  grid-template-columns: 220px minmax(0,1fr);
  gap: 3.5rem;
  border-top: 1px solid var(--line);
  padding-top: 2.8rem;
}

.section-nav {
  align-self: start;
  position: sticky;
  top: 2rem;
  font-size: .91rem;
}

.section-nav>p {
  font-size: .76rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 1rem;
}

.section-nav a {
  display: block;
  padding: .55rem .9rem;
  border-left: 2px solid var(--line);
  color: var(--muted);
  text-decoration: none;
  line-height: 1.5;
}

.section-nav a:hover,
.section-nav a[aria-current=page] {
  color: var(--blue);
  background: var(--wash);
  border-color: var(--blue);
}

.sidebar-rule {
  height: 1rem;
}

.topic-overview {
  padding-bottom: 2rem;
}

.research-links {
  margin-top: -1rem;
  margin-bottom: 2.5rem;
}

.topic-questions {
  margin: 1.4rem 0 0;
  padding-left: 1.3rem;
  color: var(--muted);
}

.topic-questions li {
  margin: .6rem 0;
  padding-left: .25rem;
}

.publication-section {
  margin-bottom: 3.5rem;
  scroll-margin-top: 2rem;
}

.publication-section>.section-heading {
  padding-bottom: 1.15rem;
  border-bottom: 1px solid var(--line);
  margin-bottom: 1.5rem;
}

.section-meta {
  color: var(--muted);
  font-size: .85rem;
}

.publication-layout .publication h3 {
  font-size: 1.15rem;
}

/* Teaching and CV timelines */
.timeline-row {
  display: grid;
  grid-template-columns: 220px minmax(0,1fr);
  gap: 2.2rem;
  padding: 1.6rem 0;
  border-top: 1px solid var(--line);
}

.timeline-row:first-child {
  border: 0;
  padding-top: 0;
}

.timeline-date {
  font-size: .91rem;
  color: var(--muted);
  padding-top: .2rem;
  font-variant-numeric: tabular-nums;
}

.timeline-row p {
  color: var(--muted);
  margin-top: .3rem;
}

.timeline-row .row-note {
  font-size: .92rem;
  margin-top: .5rem;
}

.course+.course {
  margin-top: 1.1rem;
}

.course p a {
  color: var(--muted);
}

.cv-download {
  margin: -1.8rem 0 2.6rem;
}

.button-link {
  display: inline-block;
  background: var(--blue);
  color: white;
  padding: .6rem 1rem;
  text-decoration: none;
  font-size: .92rem;
}

.button-link:hover {
  background: #163e9f;
}

.cv-section {
  padding-bottom: 3rem;
  scroll-margin-top: 2rem;
}

.cv-section /* Teaching and CV timelines */
.timeline-row {
  grid-template-columns: 180px minmax(0,1fr);
  gap: 1.6rem;
}

.cv-section+.cv-section {
  border-top: 1px solid var(--line);
  padding-top: 2.8rem;
}

/* Contact page */
.contact-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 6rem;
}

.email-large {
  font-family: var(--serif);
  font-size: clamp(1.7rem,3vw,2.4rem);
  text-decoration: none;
  overflow-wrap: anywhere;
}

.contact-block {
  margin-top: 2.4rem;
}

.contact-block h2 {
  font-size: 1.7rem;
  margin-bottom: 1rem;
}

.contact-block p,
.contact-block address {
  font-style: normal;
  color: var(--muted);
}

.contact-profiles {
  padding: 2rem 2.3rem;
  background: var(--wash);
  align-self: start;
  border-top: 3px solid var(--blue);
}

.contact-profiles h2 {
  font-size: 1.8rem;
  margin-bottom: 1.6rem;
}

.profile-link {
  display: block;
  text-decoration: none;
  padding: 1rem 0;
  border-top: 1px solid var(--line);
}

.profile-link span {
  font-weight: 600;
  font-size: 1rem;
}

.profile-link small {
  display: block;
  color: var(--muted);
  font-size: .85rem;
  margin-top: .1rem;
}

.office-note {
  margin-top: 1rem;
}

.footer-divider {
  padding: 0 .5rem;
  color: #8893a2;
}

main:focus {
  outline: none;
}

[hidden] {
  display: none!important;
}

/* Tablet layouts */
@media (max-width: 980px) {
  .reading-layout,
  .publication-layout {
    grid-template-columns: 170px minmax(0,1fr);
    gap: 2rem;
  }

  .cv-section /* Teaching and CV timelines */
.timeline-row {
    grid-template-columns: 1fr;
    gap: .6rem;
  }

  /* Contact page */
.contact-grid {
    gap: 3rem;
  }

  /* Teaching and CV timelines */
.timeline-row {
    grid-template-columns: 170px minmax(0,1fr);
  }

}

/* Mobile layouts */
@media (max-width: 700px) {
  /* Interior pages and section navigation */
.page-heading {
    padding: 1.7rem 0 2.5rem;
  }

  .breadcrumbs {
    margin-bottom: 1.7rem;
    font-size: .81rem;
  }

  .page-intro {
    font-size: 1.05rem;
  }

  .reading-layout,
  .publication-layout {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding-top: 1.8rem;
  }

  .section-nav {
    position: static;
    display: flex;
    flex-wrap: wrap;
    gap: .3rem .6rem;
  }

  .section-nav>p {
    width: 100%;
    margin-bottom: .5rem;
  }

  .section-nav a {
    padding: .35rem .6rem;
    font-size: .86rem;
  }

  .sidebar-rule {
    display: none;
  }

  .timeline-row,
  .cv-section /* Teaching and CV timelines */
.timeline-row {
    grid-template-columns: 1fr;
    gap: .65rem;
  }

  /* Contact page */
.contact-grid {
    grid-template-columns: 1fr;
    gap: 2.4rem;
  }

  .contact-profiles {
    padding: 1.7rem;
  }

  .publication-section {
    margin-bottom: 2.5rem;
  }

  .cv-download {
    margin-top: -1.2rem;
  }

}

/* Printing */
@media print {
  .site-header,
  .site-footer,
  .section-nav,
  .skip-link,
  .inline-links,
  .paper-links,
  .cv-download {
    display: none;
  }

  .container {
    width: 100%;
  }

  /* Interior pages and section navigation */
.page-heading {
    padding: 1rem 0;
  }

  .breadcrumbs {
    display: none;
  }

  .reading-layout,
  .publication-layout {
    display: block;
    border: 0;
    padding: 0;
  }

  .home-intro {
    padding: 1rem 0;
    gap: 2rem;
  }

  .portrait {
    max-width: 180px;
  }

  .publication,
  .timeline-row,
  .research-item {
    break-inside: avoid;
  }

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

  h1 {
    font-size: 30pt;
  }

  h2 {
    font-size: 22pt;
  }

  body {
    font-size: 11pt;
  }

  .contact-profiles {
    background: none;
  }

  .cv-section {
    padding-bottom: 1rem;
  }

  .publication-section {
    margin-bottom: 1.5rem;
  }

}