:root {
  --primary-color: #2563eb;
  --bg-color: #f8fafc;
  --text-color: #1e293b;
  --text-light: #64748b;
  --card-bg: #ffffff;
  --header-bg: #0f172a;
  --border-color: #e2e8f0;
}

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

header {
  background: var(--header-bg);
  color: white;
  padding: 60px 20px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

header::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(135deg, rgba(37,99,235,0.2) 0%, rgba(15,23,42,0) 100%);
  pointer-events: none;
}

.header-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 30px;
  max-width: 900px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

@media (min-width: 600px) {
  .header-content {
    flex-direction: row;
    text-align: left;
  }
}

#profile-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--card-bg);
  background-color: var(--card-bg);
  box-shadow: 0 10px 25px rgba(0,0,0,0.5);
  transition: transform 0.3s ease;
}

#profile-photo:hover {
  transform: scale(1.05);
}

h1 {
  margin: 0 0 10px 0;
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.5px;
}

#headline {
  font-size: 1.2rem;
  color: #cbd5e1;
  margin: 0 0 20px 0;
  font-weight: 400;
}

.links {
  display: flex;
  gap: 15px;
  flex-wrap: wrap;
  justify-content: center;
}

@media (min-width: 600px) {
  .links {
    justify-content: flex-start;
  }
}

.links a {
  background: rgba(255,255,255,0.1);
  padding: 8px 16px;
  border-radius: 20px;
  color: white;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 600;
  transition: all 0.2s ease;
  border: 1px solid rgba(255,255,255,0.2);
}

.links a:hover {
  background: white;
  color: var(--header-bg);
  transform: translateY(-2px);
}

section {
  max-width: 900px;
  margin: 40px auto;
  padding: 40px;
  background: var(--card-bg);
  border-radius: 16px;
  box-shadow: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -1px rgba(0,0,0,0.03);
  animation: fadeIn 0.5s ease-out forwards;
}

h2 {
  border-bottom: 2px solid var(--primary-color);
  padding-bottom: 10px;
  margin-top: 0;
  color: var(--header-bg);
  display: inline-block;
  font-size: 1.5rem;
}

h3 {
  margin: 0 0 5px 0;
  color: var(--header-bg);
}

b {
  color: var(--primary-color);
}

ul {
  padding-left: 20px;
}

li {
  margin-bottom: 8px;
  color: var(--text-color);
}

#experience > div, #education > div {
  margin-bottom: 25px;
  padding-bottom: 25px;
  border-bottom: 1px solid var(--border-color);
}

#experience > div:last-child, #education > div:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: none;
}

.publication {
  margin-bottom: 20px;
  padding: 20px;
  background: var(--bg-color);
  border-radius: 8px;
  border-left: 4px solid var(--primary-color);
  transition: transform 0.2s ease;
}

.publication:hover {
  transform: translateX(5px);
}

.publication p {
  margin: 5px 0;
}

.filters {
  margin-bottom: 20px;
  display: flex;
  gap: 10px;
}

.filters button {
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  color: var(--text-color);
  padding: 8px 16px;
  border-radius: 20px;
  cursor: pointer;
  font-weight: 600;
  transition: all 0.2s ease;
  font-family: inherit;
}

.filters button:hover, .filters button:active {
  background: var(--primary-color);
  color: white;
  border-color: var(--primary-color);
}

footer {
  text-align: center;
  padding: 20px;
  color: var(--text-light);
  margin-top: 40px;
  border-top: 1px solid var(--border-color);
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}