:root {
  --primary-color: #2c3e50;
  --accent-color: #3498db;
  --text-color: #333;
  --bg-color: #f9f9f9;
}

body {
  margin: 0;
  font-family: "Inter", -apple-system, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background: var(--bg-color);
}

.container {
  max-width: 900px;
  margin: 3rem auto;
  padding: 0 2rem;
}

header {
  text-align: center;
  margin-bottom: 30px;
}

.profile-img {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.research-img {
  display: block;
  width: 400px;
  height: auto;
  margin: 0 auto;
}

h1 {
  margin: 20px 0 0;
  font-size: 2.5rem;
  color: var(--primary-color);
}

h2 {
  margin-bottom: 1rem;
  padding-bottom: 10px;
  /*border-bottom: 2px solid #ccc;*/
  color: var(--primary-color);
  font-size: 1.5rem;
}

a,
a:visited {
  color: var(--text-color);
}

a:hover {
  color: var(--accent-color);
}

.summary-title {
  font-weight: bold;
  cursor: pointer;
  margin-bottom: 1rem;
  padding-bottom: 10px;
  border-bottom: 2px solid #ccc;
  color: var(--primary-color);
  font-size: 1.5rem;
}

section {
  margin-bottom: 30px;
}

.social-links {
  text-align: center;
  margin: 20px 0;
}

.social-links a,
.social-links a:visited {
  margin: 0 2px;
  color: var(--accent-color);
  text-decoration: none;
  font-weight: 700;
  font-size: 0.9rem;
}

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

footer {
  margin-top: 50px;
  text-align: center;
  font-size: 0.8rem;
  color: #aaa;
}

/* Top navigation */
.top-nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 2rem;
  padding-bottom: 1rem;
  margin-bottom: 2rem;
  border-bottom: 2px solid #ccc;
}

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

.top-nav a.active {
  font-weight: bold;
}

/* Mobile */
@media (max-width: 700px) {
  .container {
    margin: 1.5rem auto;
    padding: 0 1rem;
    box-sizing: border-box;
  }
}