:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f4f5f7;
  --color-text: #1a1a1a;
  --color-muted: #5a5a5a;
  --color-accent: #2b5fad;
  --color-accent-hover: #1c4483;
  --color-border: #e2e4e8;
  --max-width: 780px;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #14161a;
    --color-bg-alt: #1c1f24;
    --color-text: #eaeaea;
    --color-muted: #a6a6a6;
    --color-accent: #6fa1e8;
    --color-accent-hover: #91b8ef;
    --color-border: #2c3038;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  line-height: 1.6;
}

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

img { max-width: 100%; height: auto; }

/* Header / nav */
.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

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

.site-nav ul {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1rem;
  margin: 0;
  padding: 0;
}

.site-nav a {
  display: inline-block;
  padding: 0.35rem 0.1rem;
  color: var(--color-text);
  border-bottom: 2px solid transparent;
}

.site-nav a:hover { text-decoration: none; border-bottom-color: var(--color-border); }
.site-nav a.active { color: var(--color-accent); border-bottom-color: var(--color-accent); }

/* Main content */
.content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
}

.hero {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.5rem;
  margin: 2rem 0;
}

.hero-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  flex-shrink: 0;
}

.hero-text h1 { margin: 0 0 0.25rem; }
.hero-text p { margin: 0; color: var(--color-muted); }

.prose h1 { margin-top: 0; }
.prose h2 { margin-top: 2.5rem; border-bottom: 1px solid var(--color-border); padding-bottom: 0.3rem; }
.prose h3 { margin-top: 1.75rem; }

.prose ul, .prose ol { padding-left: 1.3rem; }
.prose li { margin: 0.35rem 0; }

.prose code, .prose pre code {
  font-family: "SFMono-Regular", Consolas, Menlo, monospace;
  font-size: 0.92em;
}

.prose pre {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 1rem;
  overflow-x: auto;
}

.pub-list li, .dl-list li { margin: 0.6rem 0; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  margin-top: 3rem;
  padding: 2rem 1.5rem;
  text-align: center;
  color: var(--color-muted);
}

.social-links {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem 1.5rem;
  margin: 0 0 1rem;
  padding: 0;
}

.social-links a { color: var(--color-text); }

.site-footer .contact, .site-footer .orcid { margin: 0.25rem 0; font-size: 0.9rem; }

@media (max-width: 480px) {
  .hero { flex-direction: column; text-align: center; }
  .hero-photo { width: 120px; height: 120px; }
}