body {
    font-family:'Poppins',sans-serif;
    background:#f4f6f8;
    color:#1a1a1a;
    scroll-behavior:smooth;
    transition: background 0.3s, color 0.3s;
}

body.dark-mode {
    background:#121212;
    color:#f5f5f5;
}

.navbar {
    background-color:#ffffff; /* always light */
    box-shadow:0 2px 5px rgba(0,0,0,0.1);
}

.avatar {
    width:180px;
    height:180px;
    border-radius:50%;
    object-fit:cover;
    margin-bottom:15px;
    border:3px solid #2c3e50;
}

body.dark-mode .avatar {
    border-color:#fff;
}

.social-icons a {
    font-size:1.5rem;
    margin:0 10px;
    color:#2c3e50;
}

body.dark-mode .social-icons a {
    color:#f5f5f5;
}

.social-icons a:hover {
    color:#007bff;
}

.left-panel {
    text-align:center;
    padding-top:20px; /* slightly below navbar */
}

.right-panel {
    padding:20px;
}

.card-section {
    background:#fff;
    padding:20px;
    border-radius:10px;
    margin-bottom:30px;
    box-shadow:0 3px 10px rgba(0,0,0,0.05);
    transition: background 0.3s, color 0.3s, box-shadow 0.3s;
}

body.dark-mode .card-section {
    background:#1f1f1f;
    color:#f5f5f5;
    box-shadow:0 3px 10px rgba(0,0,0,0.3);
}

.section h2 {
    border-bottom:2px solid #2c3e50;
    padding-bottom:8px;
    margin-bottom:20px;
    color:#2c3e50;
}

body.dark-mode .section h2 {
    color:#00bfff;
    border-color:#00bfff;
}

.research-focus {
    background:#e8f0fe;
    border-left:5px solid #007bff;
    padding:15px 20px;
    border-radius:5px;
    margin-bottom:20px;
}

body.dark-mode .research-focus {
    background:#0d1b2a;
    border-color:#00bfff;
}
/* Back to Top Button */
#backToTop {
  position: fixed;
  bottom: 40px;
  right: 40px;
  display: none;       /* Hidden by default */
  z-index: 99;         /* Stay on top */
  border: none;
  outline: none;
  background-color: #555;
  color: white;
  cursor: pointer;
  padding: 10px 15px;
  border-radius: 50%;
  font-size: 18px;
  transition: background-color 0.3s;
}

#backToTop:hover {
  background-color: #333;
}