/* Reset and Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  --blue-50: #eff6ff;
  --blue-500: #3b82f6;
  --blue-700: #1d4ed8;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  line-height: 1.5;
  color: var(--gray-900);
  background: #ffffff;
  font-size: 16px;
}

/* Typography */
h1 {
  font-size: 1.875rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--gray-900);
}

h2 {
  font-size: 1.5rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--gray-900);
}

h3 {
  font-size: 1.25rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--gray-900);
}

h4 {
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.5;
  color: var(--gray-900);
}

p {
  font-size: 1rem;
  line-height: 1.5;
}

a {
  color: inherit;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

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

/* Header */
header {
  position: sticky;
  top: 0;
  background: #ffffff;
  border-bottom: 1px solid var(--gray-200);
  z-index: 50;
}

nav {
  max-width: 80rem;
  margin: 0 auto;
  padding: 1rem 1.5rem;
}

nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  justify-content: center;
  list-style: none;
}

nav a {
  color: var(--gray-700);
  transition: color 0.2s;
}

nav a:hover,
nav a.active {
  color: var(--gray-900);
}

/* Main Content */
main {
  flex: 1;
}

.container {
  max-width: 80rem;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

.container-narrow {
  max-width: 56rem;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

/* Grid Layout */
.grid {
  display: grid;
  gap: 3rem;
}

.grid-cols-1-lg-3 {
  grid-template-columns: 1fr;
}

@media (min-width: 1024px) {
  .grid-cols-1-lg-3 {
    grid-template-columns: 2fr 1fr;
  }
}

/* Home Page */
.profile-section {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  align-items: flex-start;
  margin-bottom: 2rem;
}

@media (min-width: 768px) {
  .profile-section {
    flex-direction: row;
  }
}

.profile-image {
  width: auto;
  height: 12.5rem;
  border-radius: 8px;
  object-fit: cover;
  flex-shrink: 0;
}

.profile-info {
  flex: 1;
}

.profile-info h1 {
  margin-bottom: 0.5rem;
}

.profile-info .title {
  color: var(--gray-600);
  margin-bottom: 1.5rem;
}

.contact-info {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--gray-700);
}

.contact-item svg {
  width: 1rem;
  height: 1rem;
  color: var(--gray-500);
  flex-shrink: 0;
}

.academic-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1rem;
}

.academic-links a {
  color: var(--gray-600);
}

.academic-links a:hover {
  color: var(--gray-900);
}

.academic-links .separator {
  color: var(--gray-300);
}

.content-list {
  padding-left: 1.25rem;
}

.content-list li {
  margin-bottom: 0.4rem;
}

/* Announcements */
.announcements {
  background: var(--blue-50);
  border-left: 4px solid var(--blue-500);
  padding: 1.5rem;
  margin-bottom: 2rem;
}

.announcements-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.announcements-header svg {
  width: 1.25rem;
  height: 1.25rem;
  color: var(--blue-700);
}

.announcement-item {
  margin-bottom: 1rem;
}

.announcement-item:last-child {
  margin-bottom: 0;
}

.announcement-divider {
  padding-top: 1rem;
  border-top: 1px solid rgba(59, 130, 246, 0.2);
}

/* Sidebar */
.sidebar {
  background: #ffffff;
  border: 1px solid var(--gray-200);
  padding: 1.5rem;
}

.sidebar-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.sidebar-header svg {
  width: 1.25rem;
  height: 1.25rem;
  color: var(--gray-600);
}

.news-item {
  padding-bottom: 1rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--gray-200);
}

.news-item:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.news-date {
  color: var(--gray-500);
  margin-bottom: 0.25rem;
  font-size: 0.875rem;
}

.news-content {
  color: var(--gray-700);
}

.sidebar-footer {
  margin-top: 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--gray-200);
}

.sidebar-footer a {
  color: var(--gray-700);
}

.sidebar-footer a:hover {
  color: var(--gray-900);
}

/* Cards */
.card {
  background: #ffffff;
  border: 1px solid var(--gray-200);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

.card-gray {
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  padding: 1.5rem;
  margin-bottom: 1rem;
}

/* Projects Page */
.interest-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 2rem;
}

.tag {
  padding: 0.5rem 1rem;
  background: #ffffff;
  border: 1px solid var(--gray-200);
  border-radius: 9999px;
  color: var(--gray-700);
  font-size: 0.875rem;
}

/* Publications Page */
.publication-year {
  margin-bottom: 3rem;
}

.publication-item {
  border-left: 2px solid var(--gray-300);
  padding-left: 1.5rem;
  margin-bottom: 1.5rem;
}

.publication-title {
  margin-bottom: 0.5rem;
}

.publication-title a:hover {
  text-decoration: underline;
}

.publication-authors {
  color: var(--gray-600);
  margin-bottom: 0.25rem;
}

.publication-venue {
  color: var(--gray-500);
  font-style: italic;
}

/* Grants Page */
.grant-grid {
  display: grid;
  gap: 0.5rem 2rem;
  margin-bottom: 1rem;
}

@media (min-width: 768px) {
  .grant-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.grant-label {
  color: var(--gray-500);
}

.grant-grid-full {
  grid-column: 1 / -1;
}

.total-funding {
  margin-top: 3rem;
  background: var(--blue-50);
  border-left: 4px solid var(--blue-500);
  padding: 1.5rem;
}

/* Teaching Page */
.course-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.75rem;
}

.course-semester {
  color: var(--gray-600);
}

.student-info {
  background: var(--blue-50);
  border-left: 4px solid var(--blue-500);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

.past-courses-list {
  list-style: none;
}

.past-courses-list li {
  margin-bottom: 0.5rem;
  color: var(--gray-700);
}

/* News Page */
.news-timeline {
  border-left: 2px solid var(--gray-300);
  padding-left: 1.5rem;
  padding-bottom: 1.5rem;
  margin-bottom: 1.5rem;
}

.news-timeline:last-child {
  margin-bottom: 0;
}

/* Footer */
footer {
  border-top: 1px solid var(--gray-200);
  padding: 2rem 0;
}

footer .container {
  text-align: center;
  color: var(--gray-500);
  padding: 2rem 1.5rem;
}

/* Utility Classes */
.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 0.75rem; }
.mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; }
.mb-8 { margin-bottom: 2rem; }
.mb-12 { margin-bottom: 3rem; }

.mt-4 { margin-top: 1rem; }
.mt-6 { margin-top: 1.5rem; }

.text-gray-500 { color: var(--gray-500); }
.text-gray-600 { color: var(--gray-600); }
.text-gray-700 { color: var(--gray-700); }
.text-gray-900 { color: var(--gray-900); }

.leading-relaxed { line-height: 1.625; }

.space-y-2 > * + * { margin-top: 0.5rem; }
.space-y-4 > * + * { margin-top: 1rem; }
.space-y-6 > * + * { margin-top: 1.5rem; }
.space-y-8 > * + * { margin-top: 2rem; }