:root {
  --accent: #2563eb;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "SFMono-Regular", ui-monospace, Menlo, Consolas, "Liberation Mono", monospace;
  --transition: 0.2s ease;
  color-scheme: light dark;
}

.theme-light {
  --bg: #f7f7f8;
  --surface: #ffffff;
  --surface-rgb: 255, 255, 255;
  --text: #0f172a;
  --muted: #475569;
  --border: #e2e8f0;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.04);
}

.theme-dark {
  --bg: #0b1220;
  --surface: #101827;
  --surface-rgb: 16, 24, 39;
  --text: #e7ecf5;
  --muted: #cbd5e1;
  --border: #1e293b;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

* {
  box-sizing: border-box;
}

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

a {
  color: inherit;
  text-decoration: none;
}

a:hover,
a:focus-visible {
  color: var(--accent);
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--accent);
  color: #fff;
  padding: 0.5rem 1rem;
  border-radius: 0 0 0.5rem 0.5rem;
  z-index: 100;
}

.skip-link:focus-visible {
  left: 1rem;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1rem 1.5rem;
  position: sticky;
  top: 0;
  background: rgba( var(--surface-rgb, 255, 255, 255), 0.94);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}

.brand .name {
  font-weight: 700;
  font-size: 1.1rem;
}

.brand .tagline {
  margin: 0.1rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

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

.nav a {
  padding: 0.35rem 0.5rem;
  border-radius: 0.35rem;
  transition: color var(--transition), background-color var(--transition);
}

.nav a:hover,
.nav a:focus-visible {
  background-color: rgba(37, 99, 235, 0.08);
  color: var(--accent);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.6rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  transition: border-color var(--transition), background-color var(--transition), color var(--transition);
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
}

main {
  padding: 1rem 1.5rem 3rem;
  max-width: 1100px;
  margin: 0 auto;
}

.hero {
  padding: 3rem 0 2rem;
}

.hero-content {
  max-width: 820px;
  display: grid;
  gap: 1rem;
}

h1 {
  margin: 0;
  font-size: clamp(1.9rem, 3vw + 1rem, 2.8rem);
  line-height: 1.2;
}

h2 {
  margin: 0;
  font-size: 1.6rem;
}

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

.lead {
  margin: 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.eyebrow {
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-size: 0.85rem;
  color: var(--muted);
  font-weight: 600;
}

.hero-actions,
.contact-actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.65rem 1rem;
  border-radius: 0.55rem;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  font-weight: 600;
  transition: background-color var(--transition), color var(--transition), border-color var(--transition);
}

.button.primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.button.ghost:hover,
.button.ghost:focus-visible {
  border-color: var(--accent);
  color: var(--accent);
}

.button.primary:hover,
.button.primary:focus-visible {
  filter: brightness(0.95);
}

.section {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border);
}

.section-header {
  margin-bottom: 1.5rem;
}

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

.skills {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.projects {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.card {
  padding: 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 0.9rem;
  box-shadow: var(--shadow);
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.card:hover,
.card:focus-within {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(37, 99, 235, 0.08);
}

ul {
  padding-left: 1.1rem;
  margin: 0.35rem 0 0;
  color: var(--muted);
}

.project-head {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 0.5rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.55rem;
  border-radius: 999px;
  background: var(--surface);
  color: var(--text);
  border: 1px solid rgba(37, 99, 235, 0.4);
  font-size: 0.85rem;
  font-family: var(--font-mono);
}

.project p {
  margin: 0.25rem 0 0.35rem;
  color: var(--muted);
}

.project .muted {
  font-size: 0.9rem;
}

.project-link {
  color: var(--text);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-decoration-color: rgba(37, 99, 235, 0.4);
  transition: color var(--transition), text-decoration-color var(--transition);
}

.project-link:hover,
.project-link:focus-visible {
  color: var(--accent);
  text-decoration-color: var(--accent);
}

.project-list {
  color: var(--muted);
  margin: 0.25rem 0 0;
}

.inline-link {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1.5px;
}

.inline-link:hover,
.inline-link:focus-visible {
  text-decoration-color: var(--text);
}

.contact p {
  margin-top: 0;
  color: var(--muted);
}

.site-footer {
  padding: 1.5rem;
  border-top: 1px solid var(--border);
  text-align: center;
  color: var(--muted);
  font-size: 0.95rem;
  background: rgba( var(--surface-rgb, 255, 255, 255), 0.75);
}

@media (max-width: 720px) {
  .site-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .nav ul {
    flex-wrap: wrap;
  }

  .site-header {
    position: sticky;
    top: 0;
  }
}