:root {
  --primary-color:   #1e2126;
  --background-color:#1e2126;
  --text-color:      #ffffff;
  --accent-color:    #3498db;
  --card-background: #272b33;
  --light-gray:      #aaaaaa;
}
/* Light-mode overrides */
body.light-mode {
  --primary-color:   #f5f5f5;
  --background-color:#ffffff;
  --text-color:      #1e2126;
  --card-background: #f0f0f0;
  --light-gray:      #555555;
}

* {
  margin: 0; padding: 0; box-sizing: border-box;
  font-family: 'Segoe UI', sans-serif;
}
body {
  background: var(--background-color);
  color:      var(--text-color);
  line-height:1.6;
  transition: background 0.3s, color 0.3s;
}

.container {
  max-width: 1400px;
  width: 90%;
  margin: 0 auto;
  padding: 0 20px;
}

/* HEADER */
header {
  background: var(--primary-color);
  color:      var(--text-color);
  padding:    15px 0;
  position:   sticky; top:0; z-index:100;
  display:flex; align-items:center;
  transition: background 0.3s, color 0.3s;
}
nav {
  width:100%; display:flex;
  justify-content:space-between; align-items:center;
}
.logo { font-size:22px; font-weight:500; }
.nav-links { display:flex; list-style:none; }
.nav-links li { margin-left:30px; }
.nav-links a {
  color:var(--text-color); text-decoration:none;
  transition: color 0.3s;
}
.nav-links a:hover { color: var(--accent-color); }
.right-icons { display:flex; align-items:center; }
.right-icons button,
.right-icons a {
  background:none; border:none; color:var(--text-color);
  font-size:18px; cursor:pointer; margin-left:15px;
  transition: color 0.3s;
}

/* MAIN CONTENT */
.main-content { padding:40px 0; }

/* BIOGRAPHY */
.biography {
  display:flex; align-items:flex-start; gap:80px;
  padding:60px 0;
}
.profile-container { text-align:center; flex-shrink:0; }
.profile-image {
  width:240px; height:240px;
  border-radius:50%;
  overflow:hidden; background:#333;
}
.profile-image img {
  width:100%; height:100%; object-fit:cover;
}
.profile-name { font-size:2.2rem; margin-top:20px; }
.profile-title,
.profile-affiliation { color:var(--light-gray); margin-top:5px; }
.social-icons {
  display:flex; justify-content:center; gap:15px; margin-top:25px;
}
.social-icons a {
  color:var(--text-color); width:40px; height:40px;
  display:flex; align-items:center; justify-content:center;
  background:rgba(255,255,255,0.1); border-radius:50%;
  transition: background 0.3s, color 0.3s;
}
.social-icons a:hover {
  background:rgba(255,255,255,0.2); color:var(--accent-color);
}

.bio-content { flex:1; }
.rotating-text-container {
  height:4rem; margin-bottom:25px; position:relative;
}
.rotating-text {
  font-size:2.5rem; font-weight:500; display:inline-block;
  color:var(--accent-color);
}
.cursor {
  display:inline-block; width:3px; height:42px;
  background:var(--accent-color); margin-left:5px;
  animation:blink 1s infinite; vertical-align:middle;
}
@keyframes blink {
  0%,100% { opacity:1; } 50% { opacity:0; }
}
.bio-text { font-size:1.05rem; line-height:1.7; }

/* SECTIONS: Interests, Education, Experience, Publications, Awards */
.section { margin-bottom:80px; }
.section-title { font-size:2.5rem; margin-bottom:25px; }
.content-grid {
  display:grid; grid-template-columns:1fr 1fr; gap:80px;
}
.interests-list { list-style:none; }
.interests-list li {
  margin-bottom:15px; display:flex; align-items:flex-start;
}
.interests-list li::before {
  content:"\f0eb"; font-family:"Font Awesome 6 Free"; font-weight:900;
  margin-right:10px; font-size:18px; color:var(--accent-color);
}
.education-list { list-style:none; }
.education-list li { margin-bottom:20px; display:flex; align-items:flex-start; }
.education-list i { margin-right:15px; color:var(--accent-color); font-size:18px; padding-top:2px; }
.education-list div { display:flex; flex-direction:column; }
.degree { font-weight:bold; margin-bottom:3px; }
.institution { color:var(--light-gray); }

.experience-section, .publications-section, .awards-section {
  padding:60px 0;
}
.timeline { position:relative; }
.timeline::before {
  content:""; position:absolute; left:80px; top:0;
  width:2px; height:100%; background:var(--accent-color);
}
.experience-card {
  background:var(--card-background); border-radius:4px;
  padding:30px; margin-bottom:30px; margin-left:120px;
  position:relative; transition: background 0.3s;
}
.experience-card::before {
  content:""; position:absolute; width:16px; height:16px;
  background:var(--accent-color); border-radius:50%;
  left:-48px; top:30px;
}
.company-logo {
  position:absolute; left:-100px; top:18px;
  width:40px; height:40px; background:rgba(255,255,255,0.9);
  padding:5px; border-radius:4px; overflow:hidden;
}
.company-logo img {
  width:100%; height:100%; object-fit:contain;
}
.job-title { color:var(--accent-color); font-size:1.3rem; }
.company-name,
.job-date,
.job-location {
  color:var(--light-gray); font-size:0.9rem; margin-top:5px;
}
.job-description ul { padding-left:20px; margin-top:10px; }
.job-description li { margin-bottom:10px; }

.publications-header {
  margin-bottom: 30px;
}
.publications-note {
  color: var(--light-gray);
  font-size: 0.9rem;
}
.publication-card {
  background:var(--card-background); border-radius:4px;
  overflow:hidden; margin-bottom:40px;
  display: flex;
  flex-direction: row;
  transition: background 0.3s;
}
.publication-image {
  width:280px;
  height:200px;
  flex-shrink: 0;
  overflow:hidden;
}
.publication-image img,
.publication-image video {
  width:100%; height:100%; object-fit:cover;
  display:block;
}
.publication-content {
  padding:25px 30px;
  flex: 1;
}
.publication-title {
  font-size:1.2rem;
  margin-bottom: 10px;
  font-weight: 600;
  line-height: 1.4;
}
.publication-authors {
  color:var(--light-gray);
  font-size:0.9rem;
  margin-bottom:8px;
}
.publication-venue {
  color:var(--light-gray);
  font-size:0.85rem;
  margin-bottom:15px;
  font-style: italic;
}
.publication-links {
  margin-top: 15px;
}
.publication-links a {
  margin-right:12px;
  padding:6px 16px;
  border-radius:4px;
  background:rgba(52,152,219,0.1);
  color:var(--accent-color);
  text-decoration:none;
  transition:background 0.3s;
  font-size: 0.9rem;
}
.publication-links a:hover {
  background:rgba(52,152,219,0.2);
}

.award-card {
  background:var(--card-background); border-radius:4px;
  padding:30px; margin-bottom:30px;
}
.award-title { color:var(--accent-color); font-size:1.3rem; }
.award-org,
.award-date { color:var(--light-gray); margin-top:5px; }

/* CONTACT */
.contact-form {
  background:var(--card-background); padding:35px;
  border-radius:4px;
  max-width: 800px;
  margin: 0 auto;
}
.form-group { margin-bottom:20px; }
.form-group label { font-weight:500; margin-bottom:8px; display:block; }
.form-control {
  width:100%; padding:12px; border:1px solid rgba(255,255,255,0.1);
  border-radius:4px; background:rgba(255,255,255,0.05);
  color:var(--text-color);
}
.btn-submit {
  background:var(--accent-color); color:white; border:none;
  padding:12px 30px; border-radius:4px; cursor:pointer;
  font-weight:500; transition:background 0.3s;
}
.btn-submit:hover { background:#2980b9;    }

/* Email notification */
.email-notification {
  position: fixed;
  top: 20px;
  right: 20px;
  background: var(--accent-color);
  color: white;
  padding: 12px 20px;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.3);
  z-index: 1000;
  font-size: 14px;
  animation: slideIn 0.3s ease-out;
}
.email-notification.leaving {
  animation: slideOut 0.3s ease-in;
}
@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to   { transform: translateX(0);    opacity: 1; }
}
@keyframes slideOut {
  from { transform: translateX(0);    opacity: 1; }
  to   { transform: translateX(100%); opacity: 0; }
}

/* FOOTER */
footer {
  background: var(--primary-color); color:var(--text-color);
  text-align:center; padding:20px 0; margin-top:50px;
}

/* RESPONSIVE */
@media(max-width:992px) {
  .content-grid { gap:60px; }
  .biography { gap:60px; }
}

@media(max-width:768px){
  .biography { flex-direction:column; text-align:center; gap:40px; }
  .content-grid { grid-template-columns:1fr; gap:40px; }
  .experience-card { margin-left:60px; }
  .experience-card::before { left:-20px; }
  .company-logo { left:-50px; }
  .timeline::before { left:30px; }
  .container { width: 95%; }
}

@media(max-width:768px){
  .publication-card {
    flex-direction: column;
  }
  .publication-image {
    width: 100%;
    height: 220px;
  }
}

@media(max-width:480px){
  .profile-image { width:200px; height:200px; }
  .publication-image { height:180px; }
  .publication-content { padding:20px; }
  .contact-form { padding:25px; }
  .nav-links li { margin-left:15px; }
}