/* ----- Variables ----- */
:root {
  --bg: #0d1117;
  --bg-card: #161b22;
  --bg-card-hover: #21262d;
  --border: #30363d;
  --text: #e6edf3;
  --text-muted: #8b949e;
  --accent: #58a6ff;
  --accent-soft: rgba(88, 166, 255, 0.15);
  --green: #3fb950;
  --font-sans: 'DM Sans', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius: 12px;
  --radius-sm: 8px;
  --header-h: 60px;
}

/* ----- Reset & base ----- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

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

/* ----- Header ----- */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 1.25rem;
  height: var(--header-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--text);
}
.nav-logo:hover { text-decoration: none; color: var(--accent); }
.nav-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
}
.nav-links a:hover { color: var(--text); }
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
}

/* ----- Main ----- */
main { max-width: 960px; margin: 0 auto; padding: 0 1.25rem 4rem; }

/* ----- Hero ----- */
.hero {
  padding: 4rem 0 3rem;
  text-align: center;
}
.hero-avatar-wrap {
  margin-bottom: 1.25rem;
}
.hero-avatar {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  border: 3px solid var(--border);
  object-fit: cover;
}
.hero-title {
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  font-weight: 700;
  margin: 0 0 0.25rem;
}
.hero-tagline {
  font-family: var(--font-mono);
  color: var(--text-muted);
  font-size: 0.95rem;
  margin: 0 0 0.5rem;
}
.hero-bio {
  color: var(--text-muted);
  max-width: 480px;
  margin: 0 auto 0.5rem;
  font-size: 0.95rem;
}
.hero-meta {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin: 0 0 1.5rem;
}
.hero-cta {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* ----- Buttons ----- */
.btn {
  display: inline-block;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9rem;
  transition: background 0.2s, color 0.2s;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  border: none;
}
.btn-primary:hover { background: #79b8ff; text-decoration: none; }
.btn-ghost {
  background: var(--bg-card);
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-ghost:hover { background: var(--bg-card-hover); text-decoration: none; }

/* ----- Sections ----- */
.section {
  padding: 3rem 0;
  border-top: 1px solid var(--border);
}
.section--dark {
  background: var(--bg-card);
  margin: 0 -1.25rem;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
  border-radius: var(--radius);
}
.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 0.5rem;
}
.section-desc {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin: 0 0 1.5rem;
}

/* ----- About ----- */
.about-content p { margin: 0 0 0.75rem; }
.about-content p:last-child { margin-bottom: 0; }

.summary-section { padding-top: 2rem; }
.summary-infographic {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  margin-top: 0.5rem;
}
.summary-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  text-align: center;
  text-decoration: none;
  color: inherit;
  transition: border-color 0.2s, background 0.2s, transform 0.15s;
}
.summary-card:hover {
  border-color: var(--accent);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
}
.summary-card-value {
  display: block;
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--accent);
  font-family: var(--font-mono);
  line-height: 1.2;
}
.summary-card-label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* ----- Holopin Badges ----- */
.holopin-wrap {
  display: block;
  margin-top: 0.5rem;
}
.holopin-board {
  max-width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius);
}

/* ----- Projects ----- */
.projects-filters {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}
.filter-btn {
  padding: 0.4rem 0.9rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-muted);
  font-size: 0.85rem;
  cursor: pointer;
  font-family: inherit;
}
.filter-btn:hover { color: var(--text); background: var(--bg-card-hover); }
.filter-btn.active {
  background: var(--accent-soft);
  color: var(--accent);
  border-color: var(--accent);
}
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}
.projects-loading,
.projects-note {
  color: var(--text-muted);
  font-size: 0.9rem;
  grid-column: 1 / -1;
}
.projects-note { margin-top: 0.5rem; }
.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  transition: border-color 0.2s, background 0.2s;
}
.project-card:hover {
  border-color: var(--accent);
  background: var(--bg-card-hover);
}
.project-card a { color: inherit; }
.project-card a:hover { text-decoration: none; }
.project-name {
  font-weight: 600;
  font-size: 1rem;
  margin: 0 0 0.35rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.project-name a { color: var(--text); }
.project-desc {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin: 0 0 0.75rem;
  line-height: 1.45;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.project-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}
.project-lang {
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  background: var(--accent-soft);
  color: var(--accent);
}
.project-stats span { margin-right: 0.5rem; }

/* ----- Pull requests ----- */
.pr-grouped {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}
.pr-grouped .projects-loading { margin: 0; }
.pr-repo-group {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  overflow: hidden;
}
.pr-repo-group[open] .pr-repo-heading { border-bottom: 1px solid var(--border); }
.pr-repo-heading {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  margin: 0;
}
.pr-repo-heading::-webkit-details-marker { display: none; }
.pr-repo-heading::before {
  content: '▶';
  font-size: 0.65rem;
  color: var(--text-muted);
  margin-right: 0.35rem;
  transition: transform 0.2s;
}
.pr-repo-group[open] .pr-repo-heading::before { transform: rotate(90deg); }
.pr-repo-link {
  font-family: var(--font-mono);
  color: var(--accent);
}
.pr-repo-link:hover { color: var(--text); text-decoration: none; }
.pr-repo-count {
  font-size: 0.8rem;
  font-weight: 400;
  color: var(--text-muted);
  font-family: var(--font-mono);
}
.pr-repo-group .pr-grid {
  padding: 1rem 1.25rem 1.25rem;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 0.75rem;
}
.pr-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1rem;
  transition: border-color 0.2s, background 0.2s;
}
.pr-card:hover {
  border-color: var(--accent);
  background: var(--bg-card-hover);
}
.pr-card a { color: inherit; }
.pr-card a:hover { text-decoration: none; }
.pr-title {
  font-weight: 600;
  font-size: 0.9rem;
  margin: 0 0 0.4rem;
  line-height: 1.35;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  color: var(--text);
}
.pr-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem 0.75rem;
  font-size: 0.78rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}
.pr-state {
  padding: 0.12rem 0.4rem;
  border-radius: 4px;
  font-size: 0.7rem;
}
.pr-state--merged {
  background: rgba(63, 185, 80, 0.2);
  color: var(--green);
}
.pr-date { color: var(--text-muted); }
.pr-num { color: var(--text-muted); }

/* ----- Contributions ----- */
.contrib-links {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin: 0 0 1rem;
}
.contrib-links a { color: var(--accent); }
.contrib-chart-wrap {
  margin-bottom: 1.5rem;
  overflow-x: auto;
}
.contrib-chart {
  max-width: 100%;
  height: auto;
  display: block;
}
.contrib-calendar {
  min-height: 120px;
}
.contrib-loading { color: var(--text-muted); }

/* ----- Contact ----- */
.contact-links {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}
.contact-link {
  font-weight: 500;
  padding: 0.5rem 0;
}
.contact-link:hover { color: var(--accent); }

/* ----- Footer ----- */
.footer {
  text-align: center;
  padding: 2rem 1rem;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ----- Mobile ----- */
@media (max-width: 640px) {
  .nav-links {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--bg-card);
    flex-direction: column;
    padding: 1rem;
    border-bottom: 1px solid var(--border);
  }
  .nav-links.open { display: flex; }
  .nav-toggle { display: flex; }
  .hero { padding-top: 2.5rem; }
  .section { padding: 2rem 0; }
}