/* Xiangyu Tao — personal academic site */
:root {
  --bg: #f7faf7;
  --text: #182b22;
  --muted: #5b6d63;
  --accent: #14452f;
  --accent-2: #2a9d8f;
  --accent-soft: #e3efe7;
  --rule: #d8e5da;
  --link: #1f7a5c;
  --maxw: 900px;
}

* { box-sizing: border-box; }

html { font-size: 18px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Source Serif Pro", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header / nav */
header.site {
  border-bottom: 1px solid var(--rule);
  padding: 1.4rem 0 1.1rem;
}
header.site .wrap {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.6rem;
}
.site-name {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--text);
  text-decoration: none;
}
.site-name .zh {
  font-weight: 400;
  color: var(--muted);
  margin-left: 0.45em;
  font-size: 0.95em;
}
nav.main a {
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  text-decoration: none;
  margin-left: 1.1rem;
}
nav.main a:first-child { margin-left: 0; }
nav.main a:hover { color: var(--accent); }
nav.main a[aria-current="page"] {
  color: var(--accent);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 2px;
}

/* Main content */
main { padding: 2.6rem 0 3rem; }

h1 {
  font-size: 1.9rem;
  line-height: 1.25;
  margin: 0 0 1.1rem;
  font-weight: 700;
}
h2 {
  font-size: 1.25rem;
  margin: 2.2rem 0 0.8rem;
  font-weight: 700;
}
h2:first-child { margin-top: 0; }

p { margin: 0 0 1rem; }

a { color: var(--link); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: #14452f; }

.lede { font-size: 1rem; }

.muted { color: var(--muted); }

.small {
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.85rem;
  color: var(--muted);
}

/* Homepage intro */
.intro { display: flex; gap: 1.6rem; align-items: flex-start; flex-wrap: wrap; }
.intro-text { flex: 1 1 26rem; }

/* Publication list */
ol.pubs {
  list-style: none;
  margin: 0;
  padding: 0;
}
ol.pubs li {
  margin: 0 0 1.15rem;
  padding-left: 0;
}
ol.pubs .title { font-weight: 600; }
ol.pubs .venue { font-style: italic; }
.pub-year {
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  border-top: 1px solid var(--rule);
  padding-top: 1.1rem;
  margin: 1.8rem 0 0.9rem;
  font-weight: 600;
}
.award {
  display: inline-block;
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.75rem;
  background: var(--accent-soft);
  color: var(--accent);
  border-radius: 999px;
  padding: 0.1rem 0.6rem;
  margin-top: 0.25rem;
}

/* News / blog */
ul.news { list-style: none; margin: 0; padding: 0; }
ul.news li {
  display: flex;
  gap: 1rem;
  margin-bottom: 0.9rem;
  align-items: baseline;
}
ul.news .date {
  flex: 0 0 6.2rem;
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.02em;
}

article.post h1 { margin-bottom: 0.3rem; }
article.post .post-date { margin-bottom: 1.6rem; }

/* Contact list */
ul.contact { list-style: none; margin: 0; padding: 0; }
ul.contact li { margin-bottom: 0.45rem; }
ul.contact .label {
  display: inline-block;
  width: 6.5rem;
  color: var(--muted);
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.85rem;
}

/* Footer */
footer.site {
  border-top: 1px solid var(--rule);
  padding: 1.2rem 0 2rem;
}
footer.site .wrap {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

@media (max-width: 540px) {
  html { font-size: 16px; }
  nav.main a { margin-left: 0.8rem; }
  ul.news li { flex-direction: column; gap: 0.1rem; }
}

/* Header logo mark */
.site-name { display: inline-flex; align-items: center; gap: 0.55rem; }
.site-name img.mark { height: 34px; width: auto; display: block; }

/* THREADS project card */
.project-card {
  background: #fff;
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 1.3rem 1.4rem;
  margin: 0.4rem 0 1.2rem;
}
.project-card img.logo { width: min(620px, 100%); height: auto; display: block; margin: 0 auto 1.1rem; }
.project-card .tagline {
  font-family: -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent-2);
  font-weight: 600;
}

/* Headshot */
.intro img.headshot {
  width: 170px; height: 170px; border-radius: 50%;
  flex: 0 0 auto; border: 3px solid var(--accent-soft);
}
@media (max-width: 540px) { .intro img.headshot { margin: 0 auto; } }