:root {
  --navy: #111d4b;
  --navy-light: #24366f;
  --text: #171717;
  --muted: #5e626b;
  --line: #d9dce3;
  --soft: #f5f6f8;
  --page: min(1280px, calc(100vw - 80px));
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text);
  background: #ffffff;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 18px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--navy);
}

.page-shell {
  width: var(--page);
  margin-inline: auto;
}

.site-header {
  width: 100%;
  min-height: 60px;
  padding-inline: max(40px, calc((100vw - 1280px) / 2));
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--navy);
}

.wordmark {
  color: #ffffff;
  text-decoration: none;
}

.wordmark-mark {
  display: none;
}

.wordmark-name {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 34px;
}

.site-nav a {
  padding: 18px 0 15px;
  color: rgba(255, 255, 255, 0.78);
  border-bottom: 3px solid transparent;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-decoration: none;
  text-transform: uppercase;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] {
  color: #ffffff;
  border-bottom-color: #ffffff;
}

.hero {
  min-height: calc(100vh - 151px);
  padding: 82px 0 96px;
  display: grid;
  grid-template-columns: minmax(240px, 280px) minmax(0, 560px);
  align-items: center;
  justify-content: center;
  gap: clamp(48px, 7vw, 82px);
}

.hero h1 {
  margin: 0;
  color: var(--navy);
  font-size: clamp(30px, 3.2vw, 40px);
  font-weight: 800;
  letter-spacing: 0.035em;
  line-height: 1.15;
  text-transform: uppercase;
}

.portrait-wrap {
  width: 100%;
  margin: 0;
  padding: 9px;
  border: 1px solid var(--line);
  background: #ffffff;
  box-shadow: 12px 12px 0 #eef0f5;
}

.portrait {
  width: 100%;
  aspect-ratio: 300 / 216;
  background: url("image_siyu.jpg") center 36% / cover no-repeat;
}

.hero-aside {
  width: min(100%, 280px);
}

.hero-content {
  max-width: 760px;
}

.hero-bio {
  max-width: 520px;
  margin: 24px 0 0;
  font-size: 16px;
  line-height: 1.8;
}

.hero-bio p {
  margin: 0;
}

.hero-bio p + p {
  margin-top: 20px;
}

.hero-contact {
  margin-top: 28px;
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 8px;
  font-size: 16px;
}

.hero-contact span {
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.hero-contact a {
  color: var(--navy);
  overflow-wrap: anywhere;
}

.hero-cv {
  margin-top: 18px;
  text-align: center;
}

.cv-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding-bottom: 3px;
  color: var(--navy);
  border-bottom: 1px solid rgba(17, 29, 75, 0.45);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
}

.cv-link span {
  transition: transform 160ms ease;
}

.cv-link:hover {
  border-bottom-color: var(--navy);
}

.cv-link:hover span {
  transform: translateX(3px);
}

.papers-heading h2 {
  margin: 0;
  color: var(--navy);
  font-size: 26px;
  line-height: 1.3;
}

.research-page {
  width: min(860px, var(--page));
  padding: 55px 0 76px;
}

.papers-heading {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.papers-heading h2 {
  font-size: 26px;
}

.papers-heading p {
  margin: 0;
  color: var(--muted);
  font-size: 12px;
}

.paper {
  padding: 28px 0 29px;
  font-family: "Source Sans 3", Arial, Helvetica, sans-serif;
}

.paper + .paper {
  border-top: 1px solid #e1e6eb;
}

.paper-title-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

.paper-download {
  position: absolute;
  top: 0;
  left: 116px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 32px;
  padding-left: 18px;
  color: #506c8b;
  font-size: 15px;
  line-height: 1.5;
  text-decoration: none;
}

.paper-download::before {
  content: "";
  position: absolute;
  left: 0;
  height: 14px;
  border-left: 1px solid #e1e6eb;
}

.paper-download:hover {
  color: #263b53;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.paper h3 {
  max-width: none;
  margin: 0;
  color: #263b53;
  font-family: inherit;
  font-size: 19px;
  font-weight: 600;
  line-height: 1.5;
  overflow-wrap: break-word;
}

.paper-title-link {
  color: #263b53;
  text-decoration: none;
}

a.paper-title-link:hover {
  text-decoration: underline;
}

.paper-title-disabled {
  color: #263b53;
}

.paper-authors {
  margin: 7px 0 0;
  color: #697586;
  font-size: 16px;
  font-style: italic;
}

.paper-authors a {
  color: inherit;
  text-decoration: underline;
  text-decoration-thickness: 0.5px;
  text-decoration-color: rgba(105, 117, 134, 0.55);
  text-underline-offset: 3px;
}

.paper-authors a:hover {
  color: #263b53;
}

.paper-authors a:focus-visible {
  outline: 2px solid #506c8b;
  outline-offset: 3px;
}

.paper-content {
  position: relative;
  margin-top: 13px;
}

.paper-abstract summary {
  width: fit-content;
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 32px;
  margin: 0;
  color: #506c8b;
  cursor: pointer;
  font-size: 15px;
  font-weight: 400;
  list-style: none;
}

.paper-abstract summary::-webkit-details-marker {
  display: none;
}

.paper-abstract summary::after {
  content: "";
  width: 7px;
  height: 7px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: translateY(-2px) rotate(45deg);
  transition: transform 160ms ease;
}

.paper-abstract[open] summary::after {
  transform: translateY(2px) rotate(225deg);
}

.paper-abstract summary:hover {
  color: #263b53;
}

.paper-abstract summary:focus-visible,
.paper-download:focus-visible {
  outline: 2px solid #506c8b;
  outline-offset: 4px;
}

.paper-abstract p {
  max-width: none;
  margin: 12px 0 0;
  color: #5e6775;
  font-size: 16px;
  line-height: 1.85;
}

.paper-abstract .placeholder-copy {
  color: #8b8e95;
  font-style: italic;
}

.figure-placeholder,
.paper-figure {
  width: 100%;
  aspect-ratio: 16 / 9;
  margin: 0;
}

.figure-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: #858994;
  background: var(--soft);
  border: 1px dashed #b8bdc8;
}

.figure-placeholder svg {
  width: 55px;
  margin-bottom: 5px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.5;
}

.figure-placeholder span {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 14px;
}

.figure-placeholder small {
  margin-top: 1px;
  font-size: 10px;
}

.paper-figure {
  height: auto;
}

.paper-figure img {
  width: 100%;
  height: auto;
  display: block;
  border: 1px solid var(--line);
}

.paper-figure figcaption {
  margin-top: 6px;
  color: var(--muted);
  font-size: 11px;
}

.site-footer {
  min-height: 90px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 11px;
}

.site-footer a {
  text-decoration: none;
}

@media (max-width: 780px) {
  :root {
    --page: min(100% - 36px, 640px);
  }

  .site-header {
    padding-inline: 18px;
  }

  .hero {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    max-width: 610px;
    gap: 52px;
    padding: 60px 0 75px;
  }

  .portrait-wrap {
    width: 100%;
  }

  .hero-aside {
    width: min(280px, calc(100% - 12px));
    margin-inline: auto;
  }

  .hero-content {
    max-width: none;
  }

}

@media (max-width: 520px) {
  .site-header {
    min-height: 56px;
  }

  .wordmark-name {
    font-size: 14px;
  }

  .site-nav {
    gap: 19px;
  }

  .site-nav a {
    padding: 16px 0 13px;
    font-size: 11px;
  }

  .hero {
    padding: 46px 0 62px;
    gap: 44px;
  }

  .hero h1 {
    font-size: 30px;
  }

  .hero-bio {
    font-size: 15px;
  }

  .research-page {
    padding: 40px 0 58px;
  }

  .papers-heading {
    min-height: 68px;
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    gap: 0;
  }

  .paper {
    padding: 24px 0 27px;
  }

  .site-footer {
    min-height: 82px;
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    gap: 0;
  }

  .site-footer p {
    margin: 0;
  }
}