:root {
  --bg: #f6f8fc;
  --surface: #ffffff;
  --text: #202939;
  --muted: #59647a;
  --accent: #1f5ebf;
  --accent-weak: #e7efff;
  --border: #dde4f0;
  --shadow: 0 12px 30px rgba(20, 42, 80, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, #f8faff, var(--bg));
  line-height: 1.6;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: min(1080px, 92%);
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
}

.brand {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text);
}

.main-nav {
  display: flex;
  gap: 1.1rem;
}

.main-nav a {
  color: var(--text);
  font-weight: 600;
}

.menu-toggle {
  display: none;
}

.section {
  padding: 3.5rem 0;
}

.about-grid {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 1.5rem;
}

.profile-card,
.bio-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
  padding: 1.5rem;
}

.avatar {
  width: 160px;
  height: 160px;
  object-fit: cover;
  border-radius: 999px;
  display: block;
  margin-bottom: 0.75rem;
}

.role {
  margin: 0;
  color: var(--muted);
}

.links {
  list-style: none;
  padding: 0;
  margin: 1rem 0 0;
  display: grid;
  gap: 0.35rem;
}

.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.education-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 0.65rem;
}

.education-list li span {
  display: block;
  color: var(--muted);
}

.section-grid {
  display: grid;
  grid-template-columns: 250px 1fr;
  gap: 1.5rem;
}

.section-title h2 {
  margin-top: 0.25rem;
}

.project-grid {
  display: grid;
  gap: 1rem;
}

.project-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 1rem;
}

.project-card h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.project-card p {
  margin: 0.35rem 0;
}

.pub-list {
  margin: 0;
  padding-left: 1rem;
  display: grid;
  gap: 1rem;
}

.pub-list li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 1rem;
}

.pub-list p {
  margin: 0 0 0.6rem;
}

.btn {
  display: inline-block;
  background: var(--accent-weak);
  color: var(--accent);
  border: 1px solid #cddcfd;
  border-radius: 999px;
  padding: 0.35rem 0.75rem;
  font-size: 0.9rem;
  font-weight: 700;
}

.all-pubs {
  margin-top: 1rem;
}

.contact-list {
  list-style: none;
  padding: 0;
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 1rem;
  display: grid;
  gap: 0.6rem;
}

.site-footer {
  border-top: 1px solid var(--border);
  padding: 1rem 0 2rem;
  color: var(--muted);
}

@media (max-width: 900px) {
  .about-grid,
  .section-grid,
  .two-col {
    grid-template-columns: 1fr;
  }

  .menu-toggle {
    display: inline-block;
    border: 1px solid var(--border);
    background: #fff;
    border-radius: 8px;
    padding: 0.35rem 0.7rem;
    font-weight: 600;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    padding: 0.75rem 4%;
    flex-direction: column;
    gap: 0.5rem;
  }

  .main-nav.is-open {
    display: flex;
  }
}