:root {
  --text: rgba(0, 0, 0, 0.8);
  --muted: rgba(0, 0, 0, 0.58);
  --heading: #313131;
  --link: #0095eb;
  --link-dark: #0079c1;
  --line: #e6eaee;
  --soft: #f7f7f7;
  --white: #ffffff;
  --nav: #34495e;
  --shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.11);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  margin: 0;
  padding-top: 70px;
  color: var(--text);
  font-family: "Noto Sans SC", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
  background: var(--white);
}

a {
  color: var(--link);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover,
a:focus {
  color: var(--link-dark);
}

h1,
h2,
h3 {
  margin: 0;
  color: var(--heading);
  font-family: "Montserrat", "Noto Sans SC", sans-serif;
  font-weight: 400;
  line-height: 1.25;
}

p,
ul,
ol {
  margin-top: 0;
}

.site-header {
  position: fixed;
  z-index: 10;
  top: 0;
  left: 0;
  right: 0;
  background: var(--white);
  box-shadow: var(--shadow);
}

.navbar {
  min-height: 70px;
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  color: #2b2b2b;
  font-family: "Montserrat", "Noto Sans SC", sans-serif;
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 20px;
}

.nav-links a {
  color: var(--nav);
  font-size: 0.8rem;
  font-weight: 700;
  white-space: nowrap;
}

.nav-links a:hover {
  color: var(--link);
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 9px;
  border: 0;
  background: transparent;
  cursor: pointer;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  margin: 5px 0;
  background: var(--nav);
}

.wrapper {
  width: min(1000px, calc(100% - 32px));
  margin: 0 auto;
}

.home-section {
  padding: 96px 0;
  background: var(--white);
}

.home-section:nth-of-type(even) {
  background: var(--soft);
}

.intro-section {
  padding-top: 58px;
}

.intro-grid {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: 64px;
  align-items: start;
}

.profile {
  text-align: center;
  padding: 20px 0;
}

.portrait {
  width: 200px;
  height: 200px;
  margin: 0 auto 20px;
  border-radius: 50%;
  display: block;
  object-fit: cover;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.12);
}

.profile h1 {
  font-size: 1.75rem;
  font-weight: 300;
  color: #000;
  margin-bottom: 8px;
}

.role,
.organization {
  color: rgba(0, 0, 0, 0.54);
  font-size: 1rem;
  margin-bottom: 10px;
}

.organization {
  font-size: 0.88rem;
}

.profile-links {
  display: inline-flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 20px;
}

.profile-links a {
  min-width: 72px;
  padding: 7px 12px;
  border: 1px solid var(--link);
  border-radius: 4px;
  color: var(--link);
  font-size: 0.78rem;
  font-weight: 700;
}

.profile-links a:hover {
  background: var(--link);
  color: var(--white);
}

.intro-content h2,
.section-heading h2 {
  font-size: 1.7rem;
  margin-bottom: 24px;
}

.intro-content p {
  font-size: 0.98rem;
}

.eyebrow {
  margin-bottom: 8px;
  color: #9a9a9a;
  font-family: "Montserrat", "Noto Sans SC", sans-serif;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.info-table {
  margin-top: 28px;
  border-top: 1px solid var(--line);
}

.info-table div {
  display: grid;
  grid-template-columns: 104px minmax(0, 1fr);
  gap: 20px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.info-table span {
  color: var(--muted);
  font-size: 0.86rem;
}

.info-table strong {
  font-size: 0.9rem;
  font-weight: 500;
}

.two-column {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 60px;
}

.section-heading {
  position: sticky;
  top: 100px;
  align-self: start;
}

.content-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px 32px;
}

.content-list article,
.course-grid article {
  border-top: 2px solid var(--line);
  padding-top: 16px;
}

.content-list h3,
.course-grid h3 {
  margin-bottom: 10px;
  font-size: 1rem;
  font-weight: 700;
}

.content-list p,
.course-grid p {
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 0;
}

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

.timeline li {
  display: grid;
  grid-template-columns: 86px minmax(0, 1fr);
  gap: 22px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.timeline span {
  color: var(--link);
  font-family: "Montserrat", "Noto Sans SC", sans-serif;
  font-weight: 700;
}

.timeline p {
  margin-bottom: 0;
}

.project-list {
  margin: 0;
  padding-left: 1.2rem;
}

.project-list li {
  padding: 14px 0 14px 8px;
  border-bottom: 1px solid var(--line);
}

.project-list strong {
  display: block;
  color: var(--heading);
  font-size: 0.96rem;
  font-weight: 700;
}

.project-list span {
  display: block;
  color: var(--muted);
  font-size: 0.84rem;
  margin-top: 4px;
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px 32px;
}

.publication-list p {
  position: relative;
  margin-bottom: 18px;
  padding-left: 44px;
  font-size: 0.86rem;
  line-height: 1.58;
}

.publication-list p span {
  position: absolute;
  left: 0;
  top: 0;
  color: var(--link);
  font-family: "Montserrat", "Noto Sans SC", sans-serif;
  font-weight: 700;
}

.publication-list em {
  color: #168c2f;
  font-style: normal;
}

details {
  margin-top: 18px;
}

summary {
  width: fit-content;
  margin-bottom: 18px;
  color: var(--link);
  cursor: pointer;
  font-size: 0.88rem;
  font-weight: 700;
}

.contact-block {
  margin: 0;
  font-style: normal;
}

.contact-block p {
  display: grid;
  grid-template-columns: 90px minmax(0, 1fr);
  gap: 24px;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.contact-block strong {
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer {
  padding: 38px 0;
  color: #899596;
  background: var(--white);
  text-align: center;
}

.site-footer p {
  margin-bottom: 0;
  font-size: 0.75rem;
}

@media (min-width: 58em) {
  html {
    font-size: 20px;
  }
}

@media (max-width: 1200px) {
  body {
    padding-top: 52px;
  }

  .navbar {
    min-height: 52px;
  }

  .menu-toggle {
    display: block;
  }

  .nav-links {
    position: absolute;
    top: 52px;
    left: 0;
    right: 0;
    display: none;
    padding: 10px 16px 16px;
    background: var(--white);
    box-shadow: var(--shadow);
  }

  .nav-links.is-open {
    display: grid;
    gap: 4px;
  }

  .nav-links a {
    padding: 8px max(16px, calc((100vw - 1000px) / 2));
    line-height: 1.4;
  }
}

@media (max-width: 820px) {
  .home-section {
    padding: 62px 0;
  }

  .intro-section {
    padding-top: 42px;
  }

  .intro-grid,
  .two-column {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .section-heading {
    position: static;
  }

  .content-list,
  .course-grid {
    grid-template-columns: 1fr;
  }

  .intro-content h2,
  .section-heading h2 {
    font-size: 1.45rem;
  }
}

@media (max-width: 520px) {
  .wrapper,
  .navbar {
    width: min(100% - 24px, 1000px);
  }

  .portrait {
    width: 176px;
    height: 176px;
  }

  .info-table div,
  .timeline li,
  .contact-block p {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .publication-list p {
    padding-left: 0;
  }

  .publication-list p span {
    position: static;
    display: inline-block;
    margin-right: 6px;
  }
}