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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen,
    Ubuntu, Cantarell, sans-serif;
  line-height: 1.6;
  color: #333;
  background-color: #fdfdfd;
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
header {
  background: white;
  border-bottom: 1px solid #e9ecef;
  padding: 40px 0;
}

.header-content {
  display: flex;
  align-items: center;
  gap: 40px;
}

.profile-section {
  flex-shrink: 0;
}

.profile-img {
  width: 250px;
  height: 250px;
  border-radius: 50%;
  margin: 0 auto 30px;
  border: 4px solid rgba(255, 255, 255, 0.3);
}

.profile-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
}

.info-section {
  flex: 1;
}

a {
  cursor: pointer;
}

h1 {
  font-size: 2.2rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: #2c3e50;
}

.subtitle {
  font-size: 1.1rem;
  color: #666;
  margin-bottom: 15px;
}

.bio-brief {
  color: #555;
  line-height: 1.6;
  margin-bottom: 20px;
  max-width: 600px;
}

.contact-info {
  display: flex;
  gap: 25px;
  flex-wrap: wrap;
}

.contact-item {
  color: #667eea;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

.contact-item:hover {
  color: #764ba2;
}

/* Navigation */
nav {
  background: #f8f9fa;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

nav ul {
  display: flex;
  justify-content: center;
  list-style: none;
  padding: 15px 0;
  flex-wrap: wrap;
}

nav li {
  margin: 0 25px;
}

nav a {
  text-decoration: none;
  color: #333;
  font-weight: 500;
  padding: 10px 0;
  border-bottom: 2px solid transparent;
  transition: all 0.3s;
}

nav a:hover {
  color: #667eea;
  border-bottom-color: #667eea;
}

/* Main Content */
main {
  padding: 60px 0;
}

section {
  margin-top: 40px;
  margin-bottom: 40px;
}

h2 {
  font-size: 2rem;
  color: #2c3e50;
  margin-bottom: 30px;
  position: relative;
  padding-bottom: 10px;
}

h2:after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 50px;
  height: 3px;
  background: linear-gradient(135deg, #667eea, #764ba2);
}

/* About Section */
.about-content {
  font-size: 1.1rem;
  line-height: 1.8;
  color: #555;
}

.about-content p {
  margin-bottom: 20px;
}

/* News Section */
.news-list {
  list-style: none;
  max-height: 350px;
  overflow-y: auto;
  padding-right: 10px;
}

.news-item {
  display: flex;
  gap: 20px;
  padding: 20px;
  background: #f8f9fa;
  border-radius: 8px;
  margin-bottom: 15px;
  border-left: 4px solid #667eea;
}

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

.news-date {
  font-weight: bold;
  color: #667eea;
  min-width: 100px;
  font-size: 0.95rem;
}

.news-content {
  flex: 1;
}

/* --- Custom Scrollbar  --- */
.news-list::-webkit-scrollbar {
  width: 8px;
}

.news-list::-webkit-scrollbar-track {
  background: #f1f1f1;
  border-radius: 10px;
}

.news-list::-webkit-scrollbar-thumb {
  background: #ccc;
  border-radius: 10px;
}

.news-list::-webkit-scrollbar-thumb:hover {
  background: #aaa;
}

/* Publications Section */
.publication {
  background: white;
  padding: 25px;
  border-radius: 8px;
  margin-bottom: 25px;
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
  border: 1px solid #e9ecef;
  border-left: 4px solid #667eea;
}

.pub-title {
  font-size: 1.2rem;
  font-weight: 600;
  color: #2c3e50;
  margin-bottom: 10px;
  line-height: 1.4;
}

.pub-authors {
  color: #555;
  font-style: italic;
}

.pub-venue {
  font-weight: 500;
  color: #667eea;
}

.pub-stat {
  color: #333;
  margin-bottom: 10px;
}

.pub-links {
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
}

.pub-link {
  display: inline-block;
  padding: 6px 12px;
  background: #f1f3f4;
  color: #2c3e50;
  text-decoration: none;
  border-radius: 4px;
  font-size: 0.9rem;
  transition: background 0.3s;
}

.pub-link:hover {
  background: #667eea;
  color: white;
}

.disabled {
  opacity: 0.5;
  cursor: not-allowed;
  text-decoration: none;
}

/* Research Section */
.research-areas {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
}

.research-area {
  background: white;
  padding: 30px;
  border-radius: 8px;
  box-shadow: 0 2px 15px rgba(0, 0, 0, 0.08);
  border: 1px solid #e9ecef;
}

.research-area h3 {
  color: #2c3e50;
  margin-bottom: 15px;
  font-size: 1.3rem;
}

.research-area p {
  color: #666;
  line-height: 1.7;
}

/* Experience Section */
.experience-item {
  display: flex;
  gap: 30px;
  margin-bottom: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid #e9ecef;
}

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

.exp-date {
  min-width: 140px;
  color: #667eea;
  font-weight: 600;
  font-size: 0.95rem;
}

.exp-content h3 {
  color: #2c3e50;
  margin-bottom: 5px;
  font-size: 1.2rem;
}

.exp-company {
  color: #666;
  font-style: italic;
  margin-bottom: 15px;
}

.exp-description {
  color: #555;
  line-height: 1.7;
}

/* Skills Section */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
}

.skill-category h3 {
  color: #2c3e50;
  margin-bottom: 15px;
  font-size: 1.2rem;
}

.skill-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.skill-tag {
  background: #f8f9fa;
  color: #495057;
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 0.9rem;
  border: 1px solid #e9ecef;
}

.dark-link {
  color: #333;
  cursor: pointer;
}

/* Footer */
footer {
  background: #2c3e50;
  color: white;
  text-align: center;
  padding: 40px 0;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.footer-link {
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  transition: color 0.3s;
}

.footer-link:hover {
  color: white;
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    padding: 0 15px;
  }

  header {
    padding: 30px 0;
  }

  .header-content {
    flex-direction: column;
    text-align: center;
    gap: 25px;
  }

  .profile-img {
    margin: 0 auto 10px;
  }

  h1 {
    font-size: 1.8rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .contact-info {
    justify-content: center;
    gap: 15px;
  }

  nav ul {
    flex-direction: column;
    align-items: center;
  }

  nav li {
    margin: 5px 0;
  }

  main {
    padding: 40px 0;
  }

  section {
    margin-bottom: 50px;
  }

  h2 {
    font-size: 1.5rem;
  }

  .news-item {
    flex-direction: column;
    gap: 10px;
  }

  .news-date {
    min-width: auto;
  }

  .experience-item {
    flex-direction: column;
    gap: 15px;
  }

  .exp-date {
    min-width: auto;
  }

  .research-areas {
    grid-template-columns: 1fr;
  }

  .skills-grid {
    grid-template-columns: 1fr;
  }

  .footer-links {
    flex-direction: column;
    gap: 15px;
  }
}