*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #f0f2f5;
  --surface: #ffffff;
  --text: #1a1a2e;
  --text-muted: #5c6370;
  --accent: #2d6a9f;
  --accent-light: #e8f1f8;
  --border: #dde1e6;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: "Source Sans 3", "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.65;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.15s;
}

a:hover {
  color: #1a4f7a;
  text-decoration: underline;
}

/* Header */
.site-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 1.25rem 2rem;
}

.site-header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1000px;
  margin: 0 auto;
}

.site-name {
  font-family: "Crimson Pro", Georgia, serif;
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
}

.chinese-name {
  font-family: "Songti SC", "STSong", "SimSun", "宋体", serif;
}

.site-nav {
  display: flex;
  gap: 0.25rem;
}

.site-nav a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-muted);
  padding: 0.4rem 0.85rem;
  border-radius: 6px;
  text-decoration: none;
}

.site-nav a:hover {
  color: var(--text);
  background: var(--bg);
  text-decoration: none;
}

.site-nav a.active {
  color: var(--accent);
  background: var(--accent-light);
}

/* Main layout */
.page-body {
  display: flex;
  gap: 2.5rem;
  max-width: 1000px;
  margin: 2rem auto;
  padding: 0 2rem 4rem;
}

/* Sidebar */
.sidebar {
  flex: 0 0 240px;
}

.sidebar-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.75rem 1.5rem;
}

.photo-placeholder,
.photo {
  width: 140px;
  height: 140px;
  margin: 0 auto 1.25rem;
  border-radius: 50%;
}

.photo-placeholder {
  background: linear-gradient(135deg, #e2e8f0, #cbd5e1);
}

.photo {
  display: block;
  object-fit: cover;
}

.sidebar .name {
  font-family: "Crimson Pro", Georgia, serif;
  font-size: 1.2rem;
  font-weight: 600;
  text-align: center;
  margin-bottom: 0.2rem;
}

.sidebar .affiliation {
  font-size: 0.88rem;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 0.75rem;
}

.sidebar .email {
  font-size: 0.85rem;
  color: var(--text-muted);
  text-align: center;
  margin-bottom: 1rem;
}

.sidebar .links {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.sidebar .links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--border);
  border-radius: 50%;
  color: var(--text-muted);
  transition: color 0.15s, background 0.15s, border-color 0.15s;
}

.sidebar .links a:hover {
  background: var(--accent-light);
  border-color: var(--accent);
  color: var(--accent);
  text-decoration: none;
}

.sidebar .status {
  font-size: 0.85rem;
  color: var(--text-muted);
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  line-height: 1.5;
}

/* Main content */
.content {
  flex: 1;
  min-width: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 2rem 2.25rem;
}

.content p {
  margin-bottom: 1rem;
  color: var(--text);
}

.content h2 {
  font-family: "Crimson Pro", Georgia, serif;
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 1.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
}

.content h3 {
  font-family: "Crimson Pro", Georgia, serif;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--accent);
  margin: 2rem 0 0.6rem;
}

.content h3:first-of-type {
  margin-top: 0;
}

.divider {
  border: none;
  margin: 2rem 0;
}

/* Recent updates */
.updates-list {
  list-style: none;
}

.updates-list li {
  padding: 1rem 0 1rem 1rem;
  border-left: 3px solid var(--accent-light);
  margin-bottom: 0.75rem;
}

.updates-list li:hover {
  border-left-color: var(--accent);
}

.updates-list .date {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  background: var(--accent-light);
  padding: 0.15rem 0.55rem;
  border-radius: 4px;
  margin-bottom: 0.4rem;
}

.updates-list .desc {
  display: block;
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* Publications */
.pub-entry {
  padding: 1rem 0 1rem 1rem;
  border-left: 3px solid var(--border);
  margin-bottom: 1.25rem;
  transition: border-color 0.15s;
}

.pub-entry:hover {
  border-left-color: var(--accent);
}

.pub-entry .title {
  font-family: "Crimson Pro", Georgia, serif;
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
}

.pub-entry .authors {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 0.2rem;
}

.pub-entry .venue {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.pub-entry .venue a {
  font-weight: 600;
}

/* Research toggle */
.toggle-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent);
  cursor: pointer;
  margin-top: 0.25rem;
  display: inline-block;
}

/* Responsive */
@media (max-width: 720px) {
  .site-header-inner {
    flex-direction: column;
    gap: 0.75rem;
    align-items: flex-start;
  }

  .page-body {
    flex-direction: column;
    margin-top: 1.25rem;
  }

  .sidebar {
    flex: none;
    width: 100%;
  }

  .content {
    padding: 1.5rem;
  }
}