/* CSS Variables */
:root {
  --color-primary: #2c3e50;
  --color-secondary: #3498db;
  --color-text: #333;
  --color-text-light: #666;
  --color-background: #fff;
  --color-background-alt: #f8f9fa;
  --color-border: #e9ecef;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-serif: Georgia, "Times New Roman", serif;
  --max-width: 900px;
}

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-background);
}

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

/* Header */
.site-header {
  background-color: var(--color-primary);
  padding: 1rem 0;
}

.site-header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.site-title {
  color: #fff;
  text-decoration: none;
  font-size: 1.25rem;
  font-weight: 600;
}

.site-nav {
  display: flex;
  gap: 1.5rem;
}

.nav-link {
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.2s;
}

.nav-link:hover,
.nav-link.active {
  color: #fff;
}

/* Main content */
main {
  padding: 4.5rem 0 3rem 0;
  min-height: calc(100vh - 200px);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-primary);
  margin-top: 0;
  line-height: 1.3;
}

/* Add space before page titles (not on home page) */
main > h1 {
  margin-top: 2rem;
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.75rem; margin-top: 2rem; }
h3 { font-size: 1.35rem; }

p {
  margin: 0 0 1rem;
}

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

a:hover {
  text-decoration: underline;
}

/* Home page */
.hero {
  display: flex;
  gap: 3rem;
  align-items: flex-start;
  margin-top: 2rem;
  margin-bottom: 3rem;
}

.hero-image {
  flex-shrink: 0;
}

.hero-image img {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
}

.hero-content h1 {
  margin-bottom: 0.5rem;
}

.hero-content p {
  text-align: justify;
}

.hero-tagline {
  font-size: 1.25rem;
  color: var(--color-text-light);
  margin-bottom: 1rem;
}

.hero-links {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
}

.hero-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background-color: var(--color-background-alt);
  border-radius: 4px;
  color: var(--color-text);
  font-size: 0.9rem;
}

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

/* Publications */
.publication {
  margin-bottom: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

.publication:last-child {
  border-bottom: none;
}

.publication-title {
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}

.publication-authors {
  color: var(--color-text-light);
  font-size: 0.95rem;
  margin-bottom: 0.25rem;
}

.publication-venue {
  font-style: italic;
  color: var(--color-text-light);
  font-size: 0.9rem;
}

.publication-links {
  margin-top: 0.5rem;
}

.publication-links a {
  font-size: 0.85rem;
  margin-right: 1rem;
}

/* Teaching */
.course {
  margin-bottom: 2rem;
}

.course-title {
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 0.25rem;
}

.course-meta {
  color: var(--color-text-light);
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

/* Footer */
.site-footer {
  background-color: var(--color-background-alt);
  padding: 1.5rem 0;
  border-top: 1px solid var(--color-border);
}

.site-footer p {
  margin: 0;
  text-align: center;
  color: var(--color-text-light);
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 600px) {
  .site-header .container {
    flex-direction: column;
    gap: 1rem;
  }

  .site-nav {
    gap: 1rem;
  }

  .hero {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .hero-links {
    justify-content: center;
    flex-wrap: wrap;
  }

  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.5rem; }
}