/* ── Reset & Base ── */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #0d1117;
  --surface: #161b22;
  --border: #30363d;
  --text: #e6edf3;
  --muted: #8b949e;
  --accent: #58a6ff;
  --accent-hover: #79c0ff;
  --badge-bg: rgba(88, 166, 255, 0.15);
  --font-body: system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --max-width: 860px;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 4rem;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  animation: fadeIn 600ms ease;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 200ms ease;
}

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

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

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ── Navigation ── */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background-color: rgba(13, 17, 23, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  transition: transform 300ms ease;
}

.nav.nav-hidden {
  transform: translateY(-100%);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.75rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-name {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
}

.nav-name:hover {
  color: var(--accent);
}

.nav-links {
  display: flex;
  gap: 1.5rem;
}

.nav-links a {
  font-size: 0.85rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.nav-links a:hover {
  color: var(--accent);
}

/* ── Hero ── */
.hero {
  padding: 7rem 1.5rem 4rem;
  text-align: center;
  background: radial-gradient(ellipse at 50% 30%, rgba(88, 166, 255, 0.06) 0%, transparent 70%);
}

.hero-name {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text);
}

.hero-tagline {
  margin-top: 1rem;
  font-size: 1rem;
  font-variant: small-caps;
  letter-spacing: 0.15em;
  color: var(--muted);
  font-weight: 400;
}

/* ── Sections ── */
.section {
  padding: 5rem 1.5rem;
}

.section-heading {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 2rem;
}

/* ── About ── */
.bio-text {
  color: var(--text);
  max-width: 720px;
  line-height: 1.75;
}

/* ── Projects ── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.card {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-top: 3px solid var(--accent);
  border-radius: 6px;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.card-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text);
}

.badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--accent);
  background-color: var(--badge-bg);
  padding: 0.2em 0.7em;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.card-description {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.6;
  flex: 1;
}

.card-links {
  display: flex;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
  color: var(--accent);
}

.card-link:hover {
  color: var(--accent-hover);
}

/* ── Credentials ── */
.credentials {
  padding: 3rem 1.5rem;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.stats-row {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.stat {
  text-align: center;
}

.stat-number {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 500;
  color: var(--text);
}

.stat-label {
  font-size: 0.75rem;
  font-variant: small-caps;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.stat-divider {
  color: var(--border);
  font-size: 1.5rem;
  user-select: none;
}

/* ── Contact / Social ── */
.social-links {
  display: flex;
  gap: 2rem;
  flex-wrap: wrap;
}

.social-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--muted);
  font-size: 0.9rem;
  transition: color 200ms ease;
}

.social-link:hover {
  color: var(--accent);
}

.social-link svg {
  flex-shrink: 0;
}

/* ── Footer ── */
.footer {
  padding: 2.5rem 1.5rem;
  border-top: 1px solid var(--border);
  text-align: center;
}

.footer p {
  font-size: 0.8rem;
  color: var(--muted);
}

/* ── Responsive ── */
@media (max-width: 640px) {
  .projects-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    padding: 6rem 1.5rem 3rem;
  }

  .stats-row {
    gap: 1.25rem;
  }

  .stat-divider {
    display: none;
  }

  .social-links {
    flex-direction: column;
    gap: 1rem;
  }

  .nav-links {
    gap: 1rem;
  }

  .nav-links a {
    font-size: 0.75rem;
  }
}

/* ── Skip link (a11y) ── */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--accent);
  color: var(--bg);
  padding: 0.5rem 1rem;
  border-radius: 4px;
  font-size: 0.85rem;
  z-index: 200;
}

.skip-link:focus {
  top: 0.5rem;
}