:root {
  --blue: #2774AE;
  --dark: #1a1a1a;
  --gray: #555;
  --light-gray: #f5f5f5;
  --max-width: 720px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--dark);
  line-height: 1.7;
  font-size: 16px;
}

/* Navigation */
header {
  border-bottom: 1px solid #eee;
}

nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.2rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.site-title {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--dark);
  text-decoration: none;
}

.nav-links a {
  margin-left: 1.5rem;
  text-decoration: none;
  color: var(--gray);
  font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--blue);
}

/* Main Content */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
}

/* Profile Section */
.profile {
  display: flex;
  gap: 2rem;
  align-items: flex-start;
  margin-bottom: 2rem;
}

.profile-photo {
  width: 180px;
  height: 180px;
  border-radius: 50%;
  object-fit: cover;
  flex-shrink: 0;
}

.profile-info h1 {
  font-size: 1.6rem;
  margin-bottom: 0.3rem;
}

.profile-info .subtitle {
  color: var(--gray);
  margin-bottom: 0.8rem;
}

.social-links {
  display: flex;
  gap: 1rem;
  margin-top: 0.5rem;
}

.social-links a {
  color: var(--gray);
  text-decoration: none;
  font-size: 0.9rem;
}

.social-links a:hover {
  color: var(--blue);
}

/* Typography */
h1, h2, h3 {
  color: var(--dark);
  margin-top: 1.8rem;
  margin-bottom: 0.8rem;
}

h1 { font-size: 1.5rem; }
h2 { font-size: 1.25rem; color: var(--blue); }
h3 { font-size: 1.1rem; }

p {
  margin-bottom: 1rem;
  color: var(--dark);
}

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

a:hover {
  text-decoration: underline;
}

ul, ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.4rem;
}

/* Updates Section */
.updates {
  margin-top: 2rem;
}

.updates h2 {
  margin-bottom: 0.5rem;
}

.update-item {
  padding: 0.5rem 0;
  border-bottom: 1px solid #eee;
}

.update-date {
  font-size: 0.85rem;
  color: var(--gray);
}

/* Details/Archive */
details {
  margin-top: 1rem;
}

details summary {
  cursor: pointer;
  color: var(--blue);
  font-weight: 500;
}

/* CV and Teaching pages */
.page-title {
  font-size: 1.5rem;
  color: var(--dark);
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--blue);
}

/* Footer */
footer {
  border-top: 1px solid #eee;
  margin-top: 3rem;
}

.footer-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.5rem;
  text-align: center;
  font-size: 0.85rem;
  color: var(--gray);
}

/* Responsive */
@media (max-width: 600px) {
  .profile {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .profile-photo {
    width: 140px;
    height: 140px;
  }

  .social-links {
    justify-content: center;
  }

  nav {
    flex-direction: column;
    gap: 0.5rem;
  }

  .nav-links a {
    margin-left: 0;
    margin-right: 1rem;
  }
}