/* ===== CSS Variables ===== */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --text: #1f2937;
  --text-muted: #6b7280;
  --bg: #ffffff;
  --bg-subtle: #f9fafb;
  --border: #e5e7eb;
  --border-hover: #d1d5db;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.2s ease;
  --sidebar-width: 260px;
}

/* ===== Base Reset ===== */
*, *::before, *::after {
  box-sizing: border-box;
}

/* ===== Typography ===== */
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  margin: 0;
  padding: 0;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  color: var(--text);
  margin-top: 2rem;
  margin-bottom: 1rem;
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; border-bottom: 2px solid var(--border); padding-bottom: 0.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.1rem; }

p {
  margin: 0 0 1rem 0;
}

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

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

/* ===== Layout ===== */
.site-container {
  display: flex;
  min-height: 100vh;
}

/* ===== Sidebar ===== */
.sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  background: var(--bg-subtle);
  border-right: 1px solid var(--border);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.sidebar-inner {
  padding: 2rem 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.profile-image {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--border);
  margin-bottom: 1rem;
}

.profile-name {
  font-size: 1.25rem;
  margin: 0 0 0.5rem 0;
}

.profile-bio {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0 0 1.5rem 0;
  line-height: 1.5;
}

/* ===== Sidebar Navigation ===== */
.sidebar-nav {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  margin-bottom: 1.5rem;
}

.sidebar-nav a {
  display: block;
  padding: 0.5rem 1rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
  background: var(--bg);
  color: var(--primary);
}

/* ===== Sidebar Social Links ===== */
.sidebar-social {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.sidebar-social a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem 1rem;
  color: var(--text-muted);
  font-size: 0.875rem;
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.sidebar-social a:hover {
  background: var(--bg);
  color: var(--primary);
}

.sidebar-social svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* ===== Main Content ===== */
.main-content {
  flex: 1;
  padding: 2rem 3rem;
  max-width: 900px;
}

.main-content h2:first-child {
  margin-top: 0;
}

/* ===== News Section ===== */
.news-card {
  background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
  border: 1px solid #fcd34d;
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  position: relative;
  overflow: hidden;
  margin-bottom: 1rem;
}

.news-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: #f59e0b;
}

.news-card p {
  margin: 0;
  color: #78350f;
}

.news-card p + p {
  margin-top: 0.75rem;
}

.news-card strong {
  color: #92400e;
}

/* ===== Publications ===== */
.publications {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.pub-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  transition: all var(--transition);
}

.pub-card:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow);
}

.pub-card h4 {
  margin: 0 0 0.5rem 0;
  font-size: 1rem;
  color: var(--text);
  line-height: 1.4;
}

.pub-venue {
  display: inline-block;
  background: var(--primary);
  color: white;
  font-size: 0.7rem;
  font-weight: 600;
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  margin-left: 0.5rem;
  vertical-align: middle;
}

.pub-authors {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-bottom: 0.5rem;
}

.pub-authors em {
  color: var(--primary);
  font-style: normal;
  font-weight: 600;
}

.pub-desc {
  color: var(--text);
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.pub-note {
  color: var(--text-muted);
  font-size: 0.85rem;
  font-style: italic;
  margin-bottom: 0.5rem;
}

.pub-link {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--primary);
}

.pub-link:hover {
  text-decoration: underline;
}

/* ===== Notice ===== */
.notice {
  background: var(--bg-subtle);
  border-left: 4px solid var(--border);
  padding: 1rem 1.25rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* ===== Footer ===== */
.site-footer {
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .site-container {
    flex-direction: column;
  }

  .sidebar {
    width: 100%;
    height: auto;
    position: relative;
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .sidebar-inner {
    padding: 1.5rem;
  }

  .profile-image {
    width: 100px;
    height: 100px;
  }

  .main-content {
    padding: 1.5rem;
  }

  .pub-venue {
    display: block;
    margin-left: 0;
    margin-top: 0.5rem;
    width: fit-content;
  }
}