:root {
  color-scheme: light;
  --paper: #ffffff;
  --paper-soft: #fafafa;
  --ink: #17211f;
  --ink-muted: #5e6762;
  --line: #d8d0c1;
  --teal: #1d6f6d;
  --teal-dark: #124f4e;
  --claret: #833849;
  --gold: #a46f22;
  --green: #66775c;
  --shadow: 0 20px 48px rgba(42, 36, 26, 0.12);
  --header: rgba(255, 255, 255, 0.9);
  --radius: 8px;
  --max-width: 1160px;
  --font-sans: "Inter", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei UI", "Microsoft YaHei", Arial, sans-serif;
  --font-serif: Georgia, "Noto Serif SC", "Songti SC", "SimSun", "Times New Roman", serif;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #171b19;
  --paper-soft: #20251f;
  --ink: #f3eddf;
  --ink-muted: #bbb4a5;
  --line: #3b4039;
  --teal: #78bbb3;
  --teal-dark: #9fd4cc;
  --claret: #d78c9d;
  --gold: #d5aa62;
  --green: #a6b693;
  --shadow: 0 20px 48px rgba(0, 0, 0, 0.34);
  --header: rgba(23, 27, 25, 0.9);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  line-height: 1.72;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body.nav-open {
  overflow: hidden;
}

a {
  color: inherit;
  text-decoration-color: color-mix(in srgb, var(--teal) 65%, transparent);
  text-underline-offset: 0.2em;
}

a:hover {
  color: var(--teal-dark);
}

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

button,
input,
textarea,
select {
  font: inherit;
}

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

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 20;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 1rem;
  min-height: 72px;
  padding: 0.7rem max(1rem, calc((100vw - var(--max-width)) / 2));
  background: var(--header);
  border-bottom: 1px solid color-mix(in srgb, var(--line) 78%, transparent);
  backdrop-filter: blur(18px);
}

.site-nav {
  justify-self: center;
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.site-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 0.82rem;
  border-radius: 999px;
  color: var(--ink-muted);
  font-size: 0.94rem;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a.is-active {
  background: color-mix(in srgb, var(--teal) 12%, transparent);
  color: var(--teal-dark);
}

.header-actions {
  justify-self: end;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.language-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
  min-height: 40px;
  padding: 0.2rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--paper-soft);
}

.theme-toggle,
.nav-toggle,
.copy-button,
.filter-button,
.language-toggle button {
  border: 1px solid var(--line);
  background: var(--paper-soft);
  color: var(--ink);
  cursor: pointer;
}

.theme-toggle {
  min-width: 74px;
  min-height: 40px;
  padding: 0 0.9rem;
  border-radius: 999px;
}

.language-toggle button {
  min-width: 34px;
  min-height: 32px;
  padding: 0 0.55rem;
  border-color: transparent;
  border-radius: 999px;
  background: transparent;
  color: var(--ink-muted);
  font-size: 0.84rem;
  font-weight: 700;
}

.language-toggle button.is-active {
  background: var(--teal);
  color: #fffaf0;
}

.theme-toggle:hover,
.copy-button:hover,
.filter-button:hover,
.language-toggle button:hover {
  border-color: color-mix(in srgb, var(--teal) 60%, var(--line));
}

.nav-toggle {
  display: none;
  justify-self: end;
  width: 42px;
  height: 42px;
  padding: 0;
  border-radius: 50%;
}

.nav-toggle span:not(.sr-only) {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: currentColor;
}

.hero {
  position: relative;
  min-height: 78vh;
  max-height: 760px;
  isolation: isolate;
  display: flex;
  align-items: center;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}

.hero-media,
.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: -2;
}

.hero-media {
  background-image: url("../assets/academic-hero-abstract-world-model-mpc-final.png");
  background-size: cover;
  background-position: center;
  transform: scale(1.02);
}

.hero-overlay {
  z-index: -1;
  background:
    linear-gradient(90deg, rgba(12, 19, 18, 0.88) 0%, rgba(18, 24, 22, 0.68) 42%, rgba(18, 24, 22, 0.2) 100%),
    linear-gradient(0deg, rgba(12, 19, 18, 0.36), rgba(12, 19, 18, 0.05));
}

.hero-inner {
  width: min(var(--max-width), calc(100% - 2rem));
  margin: 0 auto;
  padding-top: 6rem;
  padding-bottom: 3rem;
  color: #fffaf0;
}

.section-label {
  margin: 0 0 0.75rem;
  color: var(--gold);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: none;
}

.hero h1 {
  max-width: 760px;
  margin: 0;
  font-family: var(--font-serif);
  font-size: 4.7rem;
  line-height: 1.03;
  font-weight: 700;
}

.hero-title-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem 1rem;
}

.hero-role {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 0.78rem;
  border: 1px solid rgba(255, 250, 240, 0.28);
  border-radius: 999px;
  background: rgba(255, 250, 240, 0.08);
  color: rgba(255, 250, 240, 0.9);
  font-family: var(--font-sans);
  font-size: 0.98rem;
  font-weight: 600;
  backdrop-filter: blur(6px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 1.75rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 1.15rem;
  border: 1px solid rgba(255, 250, 240, 0.42);
  border-radius: 999px;
  color: #fffaf0;
  font-weight: 700;
  text-decoration: none;
}

.button:hover {
  color: #fffaf0;
  transform: translateY(-1px);
}

.button-primary {
  background: rgba(255, 250, 240, 0.1);
  color: #fffaf0;
  border-color: rgba(255, 250, 240, 0.42);
  backdrop-filter: blur(6px);
}

.button-primary:hover {
  color: #fffaf0;
}

.button-secondary {
  background: rgba(255, 250, 240, 0.1);
  backdrop-filter: blur(6px);
}

.hero-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  max-width: 820px;
  margin: 2.75rem 0 0;
}

.hero-facts div {
  min-height: 84px;
  padding: 0.85rem 1.05rem;
  border-left: 2px solid var(--gold);
  background: rgba(255, 250, 240, 0.1);
  backdrop-filter: blur(8px);
}

.hero-facts dt {
  color: rgba(255, 250, 240, 0.68);
  font-size: 0.78rem;
}

.hero-facts dd {
  margin: 0.25rem 0 0;
  color: #fffaf0;
  font-weight: 700;
}

.section {
  padding: 5.5rem 0;
  border-bottom: 1px solid var(--line);
}

.section-inner {
  width: min(var(--max-width), calc(100% - 2rem));
  margin: 0 auto;
}

.two-column,
.split-list,
.contact-layout {
  display: grid;
  grid-template-columns: minmax(220px, 0.8fr) minmax(0, 1.6fr);
  gap: 4rem;
  align-items: start;
}

.section h2 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 2.45rem;
  line-height: 1.12;
}

.section h3 {
  margin: 0;
  font-size: 1.08rem;
  line-height: 1.35;
}

.about-intro {
  display: grid;
  align-content: start;
}

.profile-photo {
  width: min(230px, 100%);
  margin: 2rem 0 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--paper-soft);
  box-shadow: var(--shadow);
}

.profile-photo img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  object-position: 50% 30%;
}

.profile-photo-dark {
  display: none;
}

:root[data-theme="dark"] .profile-photo-light {
  display: none;
}

:root[data-theme="dark"] .profile-photo-dark {
  display: block;
}

.section p {
  color: var(--ink-muted);
}

.lead-block p {
  margin-top: 0;
  max-width: 820px;
  font-size: 1.04rem;
  line-height: 1.9;
  text-align: justify;
  text-justify: inter-ideograph;
}

.section-heading {
  max-width: 720px;
  margin-bottom: 2.3rem;
}

.section-heading.compact {
  margin-bottom: 1.4rem;
}

.research-grid,
.note-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.research-card,
.note-card,
.timeline-item,
.contact-card,
.publication-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper-soft);
  box-shadow: var(--shadow);
}

.research-card {
  min-height: 245px;
  padding: 1.35rem;
}

.card-index {
  display: inline-block;
  margin-bottom: 2.4rem;
  color: var(--claret);
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-weight: 700;
}

.research-card p,
.note-card p,
.timeline-item p,
.publication-item p {
  margin-bottom: 0;
}

.publications-section,
.notes-section {
  background:
    linear-gradient(180deg, color-mix(in srgb, var(--paper-soft) 64%, transparent), transparent 32%),
    var(--paper);
}

.publication-toolbar {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.25rem;
  margin-bottom: 1.25rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: color-mix(in srgb, var(--paper-soft) 70%, transparent);
}

.filter-button {
  min-height: 36px;
  padding: 0 0.95rem;
  border-radius: 999px;
  border-color: transparent;
  color: var(--ink-muted);
}

.filter-button.is-active {
  background: var(--teal);
  color: #fffaf0;
}

.publication-list {
  display: grid;
  gap: 0.9rem;
}

.publication-item {
  display: grid;
  grid-template-columns: 96px 1fr;
  gap: 1.25rem;
  padding: 1.3rem;
}

.publication-item[hidden] {
  display: none;
}

.pub-year {
  color: var(--claret);
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
}

.pub-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-top: 0.85rem;
}

.pub-links a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 0.75rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--teal-dark);
  font-size: 0.88rem;
  font-weight: 700;
  text-decoration: none;
}

.pub-links a:hover {
  border-color: var(--teal);
  background: color-mix(in srgb, var(--teal) 10%, transparent);
}

.pub-links span {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 0.75rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--teal-dark);
  font-size: 0.88rem;
  font-weight: 700;
}

.timeline {
  display: grid;
  gap: 0.85rem;
}

.timeline-item {
  position: relative;
  padding: 1.2rem 1.3rem 1.2rem 1.6rem;
  overflow: hidden;
}

.timeline-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(180deg, var(--teal), var(--gold));
}

.timeline-item span,
.note-card time {
  display: block;
  margin-bottom: 0.4rem;
  color: var(--claret);
  font-size: 0.82rem;
  font-weight: 700;
}

.note-card {
  min-height: 210px;
  padding: 1.25rem;
}

.contact-section {
  background: var(--paper-soft);
}

.contact-card {
  display: grid;
  gap: 0.65rem;
  padding: 1.4rem;
  font-style: normal;
}

.contact-card a {
  color: var(--teal-dark);
  font-size: 1.15rem;
  font-weight: 700;
}

.copy-button {
  justify-self: start;
  min-height: 40px;
  margin-top: 0.4rem;
  padding: 0 1rem;
  border-radius: 999px;
}

.copy-button.is-copied {
  background: var(--green);
  color: #fffaf0;
}

.copy-button:disabled {
  cursor: not-allowed;
  opacity: 0.62;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  width: min(var(--max-width), calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0;
  color: var(--ink-muted);
  font-size: 0.92rem;
}

@media (max-width: 980px) {
  .site-header {
    grid-template-columns: auto auto auto;
  }

  .nav-toggle {
    display: inline-block;
  }

  .site-nav {
    position: fixed;
    top: 72px;
    left: 1rem;
    right: 1rem;
    display: grid;
    gap: 0.2rem;
    padding: 0.75rem;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--paper-soft);
    box-shadow: var(--shadow);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity 180ms ease, transform 180ms ease;
  }

  .site-nav.is-open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .site-nav a {
    border-radius: var(--radius);
  }

  .hero h1 {
    font-size: 3.55rem;
  }

  .research-grid,
  .note-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .two-column,
  .split-list,
  .contact-layout {
    grid-template-columns: 1fr;
    gap: 1.7rem;
  }
}

@media (max-width: 680px) {
  .site-header {
    min-height: 64px;
    gap: 0.6rem;
    padding: 0.6rem 0.85rem;
  }

  .theme-toggle {
    min-width: 62px;
    padding: 0 0.65rem;
  }

  .header-actions {
    gap: 0.35rem;
  }

  .language-toggle {
    min-height: 38px;
  }

  .language-toggle button {
    min-width: 30px;
    padding: 0 0.42rem;
  }

  .site-nav {
    top: 64px;
  }

  .hero {
    min-height: 82vh;
  }

  .hero-inner {
    width: min(100% - 1.5rem, var(--max-width));
    padding-top: 5.4rem;
    padding-bottom: 2.2rem;
  }

  .hero h1 {
    font-size: 2.9rem;
  }

  .hero-role {
    font-size: 1rem;
  }

  .hero-actions {
    gap: 0.6rem;
  }

  .hero-facts,
  .research-grid,
  .note-grid {
    grid-template-columns: 1fr;
  }

  .hero-facts {
    gap: 0.6rem;
    margin-top: 1.85rem;
  }

  .hero-facts div {
    min-height: 76px;
    padding: 0.8rem 0.95rem;
  }

  .button {
    flex: 1 1 150px;
  }

  .research-grid,
  .note-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 4rem 0;
  }

  .section h2 {
    font-size: 2rem;
  }

  .publication-toolbar {
    width: 100%;
    overflow-x: auto;
  }

  .filter-button {
    flex: 0 0 auto;
  }

  .publication-item {
    grid-template-columns: 1fr;
    gap: 0.5rem;
    padding: 1.1rem;
  }

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

@media (max-width: 420px) {
  .theme-toggle {
    min-width: 54px;
    padding: 0 0.55rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}