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

:root {
  --color-bg: #f9f9f7;
  --color-surface: #ffffff;
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-text: #1a1a2e;
  --color-muted: #6b7280;
  --color-border: #e5e7eb;
  --color-accent: #dbeafe;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'Fira Code', 'Courier New', monospace;
  --radius: 0.5rem;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.05);
  --max-width: 900px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  font-size: 16px;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

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

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

/* ============================================================
   Navigation
   ============================================================ */
.site-header {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  padding-bottom: 1rem;
}

.site-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
}

.site-title:hover {
  color: var(--color-primary);
  text-decoration: none;
}

.site-nav {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.site-nav a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-muted);
  transition: color 0.2s;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--color-primary);
  text-decoration: none;
}

/* ============================================================
   Hero / Bio
   ============================================================ */
.hero {
  padding: 4rem 0 3rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 3rem;
  align-items: start;
}

.profile-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--color-border);
  box-shadow: var(--shadow-md);
  background: var(--color-accent);
}

.profile-photo-placeholder {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 3px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 4rem;
  box-shadow: var(--shadow-md);
}

.hero-name {
  font-size: 2.2rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 0.25rem;
}

.hero-title {
  font-size: 1.05rem;
  color: var(--color-primary);
  font-weight: 500;
  margin-bottom: 0.75rem;
}

.hero-affiliation {
  font-size: 0.95rem;
  color: var(--color-muted);
  margin-bottom: 1.25rem;
}

.hero-bio {
  font-size: 1rem;
  color: var(--color-text);
  margin-bottom: 1.5rem;
  max-width: 600px;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1.1rem;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s, color 0.2s, box-shadow 0.2s;
  text-decoration: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
  border: 1px solid var(--color-primary);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  color: #fff;
  text-decoration: none;
}

.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--color-primary);
}

.btn-outline:hover {
  background: var(--color-accent);
  color: var(--color-primary-dark);
  text-decoration: none;
}

/* ============================================================
   Sections
   ============================================================ */
.section {
  padding: 3rem 0;
  border-top: 1px solid var(--color-border);
}

.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--color-text);
}

.section-subtitle {
  font-size: 1rem;
  color: var(--color-muted);
  margin-bottom: 2rem;
}

/* ============================================================
   Publications
   ============================================================ */
.publication-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.publication-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  box-shadow: var(--shadow);
  transition: box-shadow 0.2s;
}

.publication-card:hover {
  box-shadow: var(--shadow-md);
}

.pub-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 0.25rem;
}

.pub-authors {
  font-size: 0.9rem;
  color: var(--color-muted);
  margin-bottom: 0.25rem;
}

.pub-venue {
  font-size: 0.9rem;
  font-style: italic;
  color: var(--color-muted);
  margin-bottom: 0.75rem;
}

.pub-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 500;
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
}

.tag-blue {
  background: var(--color-accent);
  color: var(--color-primary);
}

.tag-blue:hover {
  background: var(--color-primary);
  color: #fff;
  text-decoration: none;
}

.tag-gray {
  background: #f3f4f6;
  color: #374151;
}

.tag-gray:hover {
  background: #e5e7eb;
  color: #111;
  text-decoration: none;
}

.tag-green {
  background: #dcfce7;
  color: #166534;
}

.tag-green:hover {
  background: #16a34a;
  color: #fff;
  text-decoration: none;
}

/* ============================================================
   Blog
   ============================================================ */
.blog-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.blog-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  box-shadow: var(--shadow);
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  transition: box-shadow 0.2s;
}

.blog-card:hover {
  box-shadow: var(--shadow-md);
}

.blog-card-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: 0.25rem;
}

.blog-card-title a {
  color: inherit;
}

.blog-card-title a:hover {
  color: var(--color-primary);
  text-decoration: none;
}

.blog-card-excerpt {
  font-size: 0.9rem;
  color: var(--color-muted);
}

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

.blog-card-date {
  display: block;
  text-align: right;
  margin-bottom: 0.25rem;
}

.view-all-link {
  margin-top: 1.25rem;
  display: inline-block;
  font-size: 0.9rem;
  font-weight: 500;
}

/* ============================================================
   Contact
   ============================================================ */
.contact-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.95rem;
  color: var(--color-text);
}

.contact-item svg {
  color: var(--color-primary);
  flex-shrink: 0;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 0;
  margin-top: 2rem;
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-muted);
}

/* ============================================================
   Publication / Blog Page
   ============================================================ */
.page-header {
  padding: 3rem 0 2rem;
}

.page-header h1 {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.page-header .meta {
  color: var(--color-muted);
  font-size: 0.95rem;
}

.page-content {
  padding: 0 0 3rem;
}

.prose {
  max-width: 720px;
}

.prose h2 {
  font-size: 1.3rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
}

.prose h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.5rem 0 0.5rem;
}

.prose p {
  margin-bottom: 1rem;
  line-height: 1.8;
}

.prose ul, .prose ol {
  margin: 0.75rem 0 1rem 1.5rem;
}

.prose li {
  margin-bottom: 0.4rem;
}

.prose pre {
  background: #1e293b;
  color: #e2e8f0;
  padding: 1rem 1.25rem;
  border-radius: var(--radius);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  margin: 1.25rem 0;
}

.prose code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: #f1f5f9;
  padding: 0.1em 0.35em;
  border-radius: 0.25rem;
}

.prose pre code {
  background: none;
  padding: 0;
  font-size: inherit;
}

.prose blockquote {
  border-left: 4px solid var(--color-primary);
  padding-left: 1rem;
  color: var(--color-muted);
  margin: 1.25rem 0;
  font-style: italic;
}

.pub-abstract {
  background: var(--color-accent);
  border-left: 4px solid var(--color-primary);
  padding: 1rem 1.25rem;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 1.5rem 0;
  font-size: 0.95rem;
  line-height: 1.75;
}

.pub-meta-grid {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.4rem 1rem;
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.pub-meta-grid dt {
  font-weight: 600;
  color: var(--color-muted);
}

/* ============================================================
   Blog index
   ============================================================ */
.blog-page-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  padding-bottom: 3rem;
}

.blog-page-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: box-shadow 0.2s;
}

.blog-page-card:hover {
  box-shadow: var(--shadow-md);
}

.blog-page-card h2 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.3rem;
}

.blog-page-card h2 a {
  color: var(--color-text);
}

.blog-page-card h2 a:hover {
  color: var(--color-primary);
  text-decoration: none;
}

.blog-page-card .meta {
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-bottom: 0.75rem;
}

.blog-page-card .excerpt {
  font-size: 0.95rem;
  color: var(--color-text);
  line-height: 1.7;
}

/* ============================================================
   Publications index layout
   ============================================================ */
.publications-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 180px;
  gap: 2rem;
  align-items: start;
  padding-bottom: 3rem;
}

.publications-main {
  min-width: 0;
}

.publication-year-group {
  scroll-margin-top: 6rem;
  margin-bottom: 2rem;
}

.publication-year-group:last-child {
  margin-bottom: 0;
}

.publication-year-heading {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--color-text);
}

.publication-timeline {
  position: sticky;
  top: 5.5rem;
}

.publication-timeline-title {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-muted);
  margin-bottom: 0.7rem;
}

.publication-timeline-list {
  list-style: none;
  border-left: 2px solid var(--color-border);
  padding-left: 0.8rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.publication-timeline-list a {
  color: var(--color-muted);
  font-weight: 600;
  font-size: 0.92rem;
}

.publication-timeline-list a:hover {
  color: var(--color-primary);
  text-decoration: none;
}

/* ============================================================
   Back link
   ============================================================ */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.9rem;
  color: var(--color-muted);
  margin-bottom: 1.5rem;
  margin-top: 1.5rem;
}

.back-link:hover {
  color: var(--color-primary);
  text-decoration: none;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 640px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .profile-photo,
  .profile-photo-placeholder {
    width: 120px;
    height: 120px;
    font-size: 3rem;
  }

  .hero-name {
    font-size: 1.7rem;
  }

  .site-header .container {
    flex-direction: column;
    gap: 0.75rem;
    align-items: flex-start;
  }

  .site-nav {
    gap: 1.25rem;
  }

  .blog-card {
    flex-direction: column;
  }

  .blog-card-meta {
    align-self: flex-end;
  }
}

@media (max-width: 900px) {
  .publications-layout {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }

  .publication-timeline {
    position: static;
  }

  .publication-timeline-list {
    border-left: 0;
    border-top: 2px solid var(--color-border);
    padding-left: 0;
    padding-top: 0.75rem;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 0.75rem 1rem;
  }
}