/* Guanqun Cao — homepage theme */
:root {
  --bg: #FAF7F2;            /* warm off-white */
  --ink: #3D362E;           /* warm near-black */
  --muted: #8B7E6E;         /* warm gray-brown */
  --accent: #B85C38;        /* terracotta */
  --accent-dark: #9C4A2B;
  --soft: #F3EBDE;          /* soft card background */
  --card: #FFFDF8;
  --border: #E8DECF;
  --good: #5E7F5A;          /* muted green for the demo link */
  --ring: rgba(184, 92, 56, 0.16);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 900px;
  margin: 0 auto;
  padding: 56px 28px 40px;
}

/* ---------- header ---------- */

.hero {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 36px;
  align-items: center;
}

.intro h1 {
  margin: 0 0 6px;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 44px;
  font-weight: 600;
  letter-spacing: 0.5px;
  color: var(--ink);
}

.role {
  margin: 0;
  color: var(--muted);
  font-size: 16.5px;
}

/* contact icons */

.contact {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.contact a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--card);
  color: var(--ink);
  text-decoration: none;
  font-size: 15px;
  transition: transform 0.15s ease, border-color 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}

.contact a svg {
  flex: none;
}

.contact a:hover {
  transform: translateY(-2px);
  border-color: var(--accent);
  color: var(--accent-dark);
  box-shadow: 0 6px 16px var(--ring);
}

/* portrait */

.portrait {
  width: 210px;
  height: 210px;
  object-fit: cover;
  border-radius: 50%;
  border: 5px solid var(--card);
  outline: 1px solid var(--border);
  box-shadow: 0 12px 30px rgba(150, 118, 88, 0.18);
}

/* ---------- bio ---------- */

.bio {
  margin-top: 40px;
  max-width: 64ch;
}

.bio p {
  margin: 0 0 14px;
}

/* ---------- what's new ---------- */

.news {
  margin-top: 34px;
  padding: 26px 28px;
  background: var(--soft);
  border: 1px solid var(--border);
  border-radius: 18px;
}

.news-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

.news-head h2 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: 22px;
  font-weight: 600;
}

.badge {
  background: var(--accent);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  padding: 3px 10px;
  border-radius: 999px;
}

.cite {
  margin: 0;
}

.cite .title {
  font-weight: 700;
}

.cite .authors {
  color: var(--muted);
  font-size: 15.5px;
}

.news-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 20px;
  border-radius: 999px;
  text-decoration: none;
  font-size: 15px;
  font-weight: 600;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px var(--ring);
}

.btn-paper {
  background: var(--accent);
  color: #fff;
}

.btn-paper:hover { background: var(--accent-dark); }

.btn-demo {
  background: var(--card);
  color: var(--good);
  border: 1.5px solid var(--good);
}

.btn-demo:hover { background: var(--good); color: #fff; }

.btn svg { flex: none; }

/* ---------- footer ---------- */

footer {
  margin-top: 56px;
  padding: 22px 16px 34px;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--muted);
  font-size: 14.5px;
}

footer nav a {
  color: var(--muted);
  text-decoration: none;
  margin: 0 6px;
}

footer nav a:hover { color: var(--accent-dark); }

footer p { margin: 0 0 8px; }

/* ---------- responsive ---------- */

@media (max-width: 720px) {
  main { padding-top: 36px; }

  .hero { grid-template-columns: 1fr; gap: 24px; text-align: center; }

  .portrait {
    order: -1;
    width: 180px;
    height: 180px;
    margin: 0 auto;
  }

  .contact { justify-content: center; }

  .cite .authors { font-size: 15px; }
}
/* ---------- subpages ---------- */

.subpage { padding-top: 28px; }

.subpage-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 34px;
}

.subpage-nav a {
  padding: 7px 16px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--card);
  color: var(--ink);
  text-decoration: none;
  font-size: 15px;
  transition: border-color 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}

.subpage-nav a:hover {
  border-color: var(--accent);
  color: var(--accent-dark);
  box-shadow: 0 6px 16px var(--ring);
}

.subpage-content { max-width: 76ch; margin: 0 auto; }

.subpage-content h1,
.subpage-content h2,
.subpage-content h3 {
  font-family: Georgia, "Times New Roman", serif;
  font-weight: 600;
}

.subpage-content h1 { margin: 0 0 24px; font-size: 38px; }
.subpage-content h2 { margin: 0 0 14px; font-size: 24px; }
.subpage-content h3 { margin: 4px 0 18px; font-size: 20px; }
.subpage-content a { color: var(--accent-dark); }
.subpage-content a:hover { color: var(--accent); }
.post-list { margin: 0; padding-left: 1.4em; }
.post-meta { color: var(--muted); font-size: 15px; }
.subpage-content ol { padding-left: 1.5em; }
.subpage-content li { margin-bottom: 14px; }
.rss-subscribe { color: var(--muted); }

.award { color: var(--accent-dark); font-weight: 600; }