/* Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #fafaf8;
  --surface: #ffffff;
  --text: #1a1a1a;
  --text-secondary: #374151;
  --muted: #6b7280;
  --accent: #2563eb;
  --accent-light: #eff6ff;
  --border: #e5e7eb;
  --max-width: 1100px;
  --font-serif: 'Georgia', 'Times New Roman', serif;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
}

[data-theme="dark"] {
  --bg: #111110;
  --surface: #1c1c1a;
  --text: #e8e8e5;
  --text-secondary: #d1d5db;
  --muted: #9ca3af;
  --accent: #60a5fa;
  --accent-light: #172554;
  --border: #2d2d2b;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111110;
    --surface: #1c1c1a;
    --text: #e8e8e5;
    --text-secondary: #d1d5db;
    --muted: #9ca3af;
    --accent: #60a5fa;
    --accent-light: #172554;
    --border: #2d2d2b;
  }
}

html { font-size: 17px; scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover { text-decoration: underline; }

/* Layout */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Nav */
nav {
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.nav-name {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
  letter-spacing: -0.01em;
}

.nav-links {
  display: flex;
  gap: 1.75rem;
  list-style: none;
}

.nav-links a {
  color: var(--muted);
  font-size: 0.875rem;
  font-weight: 500;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--text); text-decoration: none; }

.theme-toggle {
  border: none;
  background: transparent;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--muted);
  cursor: pointer;
  font-family: var(--font-sans);
  padding: 0;
  transition: color 0.15s;
}
.theme-toggle:hover { color: var(--text); }

/* Hero */
.hero {
  padding: 3rem 0 2rem;
}

.hero-top {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3.5rem;
  align-items: start;
}

.hero-inner {
  display: flex;
  gap: 2.5rem;
  align-items: flex-start;
}

.research-themes--sidebar {
  grid-template-columns: 1fr;
  gap: 0.65rem;
}

.hero-photo {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  object-fit: cover;
  flex-shrink: 0;
  border: 3px solid var(--border);
  background: var(--border);
}

.hero-photo-placeholder {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  flex-shrink: 0;
  border: 3px solid var(--border);
  background: linear-gradient(135deg, var(--accent-light), var(--border));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.2rem;
  color: var(--accent);
  font-weight: 700;
  font-family: var(--font-serif);
}

.hero-text h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 0.4rem;
}

.hero-roles {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1rem;
}

.role-tag {
  font-size: 0.78rem;
  font-weight: 500;
  padding: 0.2rem 0.65rem;
  border-radius: 99px;
  background: var(--accent-light);
  color: var(--accent);
  border: 1px solid #bfdbfe;
}

.hero-bio {
  color: var(--text-secondary);
  font-size: 0.975rem;
  line-height: 1.7;
  margin-bottom: 1.25rem;
}

.social-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.social-link {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.825rem;
  font-weight: 500;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.3rem 0.75rem;
  background: var(--surface);
  transition: all 0.15s;
}
.social-link:hover {
  color: var(--accent);
  border-color: var(--accent);
  text-decoration: none;
}

/* Section */
section {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border);
}

section h2 {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: 1.5rem;
  color: var(--text);
}

/* Research */
.research-intro {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.75;
}

.research-themes {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.85rem;
}

.theme-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.15rem;
}

.theme-card h3 {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
  color: var(--text);
}

.theme-card p {
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.55;
}

/* Publications */
.pub-list {
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}

.pub-item {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.pub-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.4;
}
.pub-title a { color: var(--text); }
.pub-title a:hover { color: var(--accent); }

.pub-authors {
  font-size: 0.8rem;
  color: var(--muted);
}

.pub-venue {
  font-size: 0.8rem;
  color: var(--accent);
  font-weight: 500;
}

.pub-group {
  margin-bottom: 1.75rem;
}

.pub-group-label {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 0.85rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border);
}

.pub-more {
  margin-top: 0.75rem;
  font-size: 0.875rem;
}

/* Venue links */
.venue-links {
  display: inline-flex;
  gap: 0.3rem;
  margin-left: 0.5rem;
  vertical-align: middle;
}

.venue-link {
  font-size: 0.68rem;
  font-weight: 500;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0.05rem 0.4rem;
  background: var(--surface);
  transition: all 0.15s;
  white-space: nowrap;
}

.venue-link:hover {
  color: var(--accent);
  border-color: var(--accent);
  text-decoration: none;
}

/* Publications page controls */
.pub-controls {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 2rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--border);
}

.view-toggle {
  display: flex;
  gap: 3px;
  background: var(--border);
  border-radius: 8px;
  padding: 3px;
  width: fit-content;
}

.toggle-btn {
  border: none;
  background: transparent;
  padding: 0.35rem 1rem;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  color: var(--muted);
  transition: all 0.15s;
  font-family: var(--font-sans);
}

.toggle-btn.active {
  background: var(--surface);
  color: var(--text);
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
}

.topic-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.pill-row {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex-wrap: wrap;
}

.pill-row + .pill-row {
  margin-top: 0.5rem;
}

.pill-row-label {
  font-size: 0.67rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  white-space: nowrap;
  width: 48px;
  flex-shrink: 0;
}

.pill-row-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.topic-pill {
  border: 1px solid var(--border);
  background: var(--surface);
  padding: 0.25rem 0.75rem;
  border-radius: 99px;
  font-size: 0.78rem;
  font-weight: 500;
  cursor: pointer;
  color: var(--muted);
  transition: all 0.15s;
  font-family: var(--font-sans);
}

.topic-pill:hover {
  color: var(--accent);
  border-color: var(--accent);
}

.topic-pill.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.topic-pill--secondary {
  font-size: 0.73rem;
}

.topic-pill--secondary.active {
  background: var(--accent-light);
  color: var(--accent);
  border-color: var(--accent);
}

/* Publications page supercategory */
.pub-supercategory {
  margin-bottom: 2.5rem;
}

.pub-supercategory-label {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
  padding-bottom: 0.6rem;
  border-bottom: 2px solid var(--text);
  margin-bottom: 1.5rem;
}

.pub-subcategory {
  margin-bottom: 1.75rem;
  padding-left: 0.85rem;
  border-left: 3px solid var(--accent-light);
}

.pub-subcategory-label {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.85rem;
}

/* Recent */
.recent-list {
  display: flex;
  flex-direction: column;
}

.recent-item {
  display: grid;
  grid-template-columns: 80px auto 1fr;
  align-items: baseline;
  gap: 0 0.75rem;
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--border);
}
.recent-item:last-child { border-bottom: none; }

.recent-date {
  font-size: 0.78rem;
  color: var(--muted);
  white-space: nowrap;
  font-weight: 500;
}

.recent-tag {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  white-space: nowrap;
}

.recent-tag--paper    { color: var(--accent); }
.recent-tag--preprint { color: var(--muted); }
.recent-tag--press    { color: #d97706; }

.recent-content {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.45;
}

.recent-content a {
  color: var(--text);
  font-weight: 500;
}
.recent-content a:hover { color: var(--accent); text-decoration: none; }

/* Career */
.career-list {
  display: flex;
  flex-direction: column;
}

.career-item {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 1rem;
  padding: 0.9rem 0;
  border-bottom: 1px solid var(--border);
}
.career-item:last-child { border-bottom: none; }

.career-dates {
  font-size: 0.78rem;
  color: var(--muted);
  font-weight: 500;
  padding-top: 0.15rem;
  white-space: nowrap;
}

.career-role {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  line-height: 1.3;
}

.career-company {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
  margin-top: 0.1rem;
}

.career-logo {
  height: 18px;
  width: auto;
  border-radius: 3px;
  flex-shrink: 0;
}

.career-desc {
  font-size: 0.8rem;
  color: var(--muted);
  margin-top: 0.3rem;
  line-height: 1.5;
}

/* Press */
.press-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.press-item {
  display: grid;
  grid-template-columns: 110px 1fr auto;
  align-items: baseline;
  gap: 0.75rem 1rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--border);
}
.press-item:last-child { border-bottom: none; }

.press-outlet {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--muted);
  letter-spacing: 0.03em;
  text-transform: uppercase;
  white-space: nowrap;
}

.press-headline {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text);
  line-height: 1.4;
}
.press-headline:hover { color: var(--accent); text-decoration: none; }

.press-date {
  font-size: 0.78rem;
  color: var(--muted);
  white-space: nowrap;
}

@media (max-width: 600px) {
  .press-item {
    grid-template-columns: 1fr;
    gap: 0.2rem;
  }
  .press-date { display: none; }
}

/* Blog */
.blog-posts {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.blog-post {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--border);
  gap: 1rem;
}
.blog-post:last-child { border-bottom: none; }

.blog-post-title {
  font-size: 0.925rem;
  font-weight: 500;
  color: var(--text);
  flex: 1;
}
.blog-post-title:hover { color: var(--accent); text-decoration: none; }

.blog-post-date {
  font-size: 0.8rem;
  color: var(--muted);
  white-space: nowrap;
  flex-shrink: 0;
}

.blog-empty {
  font-size: 0.9rem;
  color: var(--muted);
  font-style: italic;
}

/* Open Source */
.oss-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.oss-item {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.oss-name {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--accent);
}

.oss-desc {
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.15rem;
}

/* Blog post prose */
.post-header {
  padding: 3rem 0 2rem;
}

.post-header h1 {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.25;
  margin-bottom: 0.5rem;
}

.post-meta {
  font-size: 0.85rem;
  color: var(--muted);
}

.post-body {
  max-width: 680px;
  padding: 2rem 0 4rem;
}

.post-body p {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 1.4rem;
}

.post-body h2 {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 2rem 0 0.75rem;
  color: var(--text);
}

.post-body h3 {
  font-size: 1rem;
  font-weight: 700;
  margin: 1.5rem 0 0.5rem;
  color: var(--text);
}

.post-body ul, .post-body ol {
  margin: 0 0 1.4rem 1.5rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

.post-body li { margin-bottom: 0.3rem; }

.post-body blockquote {
  border-left: 3px solid var(--accent);
  margin: 1.5rem 0;
  padding: 0.5rem 1.25rem;
  color: var(--muted);
  font-style: italic;
}

.post-body a { color: var(--accent); }

.post-back {
  font-size: 0.85rem;
  color: var(--muted);
  display: inline-block;
  margin-bottom: 1.5rem;
}
.post-back:hover { color: var(--accent); text-decoration: none; }

/* Footer */
footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  margin-top: 1rem;
  text-align: center;
}

footer p {
  font-size: 0.8rem;
  color: var(--muted);
}

/* Responsive */
@media (max-width: 800px) {
  .hero-top { grid-template-columns: 1fr; gap: 2rem; }
}

@media (max-width: 600px) {
  .hero-inner { flex-direction: column; gap: 1.25rem; }
  .research-themes { grid-template-columns: 1fr; }
  .nav-links { gap: 1rem; }
}