/* ============================================================
   CSS Variables
   ============================================================ */
:root {
  --color-bg: #ffffff;
  --color-surface: #f9f9f9;
  --color-border: #e4e4e7;
  --color-border-dashed: #c4c4cc;
  --color-text: #18181b;
  --color-text-muted: #71717a;
  --color-text-light: #a1a1aa;
  --color-accent: #18181b;
  --color-accent-hover: #3f3f46;
  --color-link: #2563eb;
  --color-link-hover: #1d4ed8;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-pill: 999px;

  --shadow-card: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.10), 0 2px 8px rgba(0,0,0,0.06);

  --max-width: 1100px;
  --section-padding: 5rem 1.5rem;
}

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

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

/* ============================================================
   Navigation
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--color-text);
  letter-spacing: -0.01em;
}
.nav-logo:hover { color: var(--color-text); opacity: 0.75; }

.nav-links {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav-links a {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  font-weight: 500;
  transition: color 0.15s;
}
.nav-links a:hover { color: var(--color-text); }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.3rem;
  cursor: pointer;
  color: var(--color-text);
  padding: 0.25rem;
}

.nav-mobile-menu {
  display: none;
  flex-direction: column;
  padding: 0.75rem 1.5rem 1rem;
  border-top: 1px solid var(--color-border);
  gap: 0.75rem;
}
.nav-mobile-menu a {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  font-weight: 500;
}
.nav-mobile-menu.open { display: flex; }

/* ============================================================
   Buttons
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 1.1rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: background 0.15s, opacity 0.15s, box-shadow 0.15s;
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-accent);
  color: #fff;
}
.btn-primary:hover {
  background: var(--color-accent-hover);
  color: #fff;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.btn-ghost {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}
.btn-ghost:hover {
  background: var(--color-surface);
  color: var(--color-text);
  border-color: var(--color-border-dashed);
}

.btn-github {
  background: #24292e;
  color: #fff;
  font-size: 0.8rem;
  padding: 0.4rem 0.85rem;
}
.btn-github:hover { background: #3f3f46; color: #fff; }

.btn-access {
  background: transparent;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  font-size: 0.8rem;
  padding: 0.4rem 0.85rem;
}
.btn-access:hover {
  background: var(--color-surface);
  color: var(--color-text);
}

.btn-sm { font-size: 0.8rem; padding: 0.35rem 0.75rem; }

/* ============================================================
   Hero
   ============================================================ */
.hero {
  padding: 6rem 1.5rem 5rem;
  text-align: center;
  border-bottom: 1px solid var(--color-border);
}

.hero-inner {
  max-width: 600px;
  margin: 0 auto;
}

.hero-name {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 0.75rem;
  color: var(--color-text);
}

.hero-tagline {
  font-size: 1.1rem;
  color: var(--color-text-muted);
  margin-bottom: 2rem;
  line-height: 1.5;
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

/* ============================================================
   Section Common
   ============================================================ */
.section-projects,
.section-blog {
  padding: var(--section-padding);
  border-bottom: 1px solid var(--color-border);
}

.section-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.4rem;
}

.section-subtitle {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  margin-bottom: 2rem;
}

/* ============================================================
   Filter Bar
   ============================================================ */
.filter-bar {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
}

.filter-btn {
  padding: 0.35rem 1rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text-muted);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  font-family: var(--font-sans);
}
.filter-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.filter-btn.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
}

/* ============================================================
   Project Cards Grid
   ============================================================ */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
}

.card {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  background: var(--color-bg);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}
.card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.card-private {
  background: var(--color-surface);
  border-style: dashed;
  border-color: var(--color-border-dashed);
}

.card-header {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  margin-bottom: 0.6rem;
}

.card-lock {
  font-size: 0.85rem;
  flex-shrink: 0;
  margin-top: 0.15rem;
  opacity: 0.6;
}

.card-title {
  font-size: 0.975rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.card-desc {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  line-height: 1.55;
  flex: 1;
  margin-bottom: 1rem;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.card-footer {
  margin-top: auto;
}

/* ============================================================
   Language Badges
   ============================================================ */
.lang-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.78rem;
  color: var(--color-text-muted);
}

.lang-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
  background: var(--color-border);
}

/* GitHub language colors */
.lang-typescript   .lang-dot { background: #3178c6; }
.lang-javascript   .lang-dot { background: #f1e05a; outline: 1px solid #d4b800; outline-offset: 0; }
.lang-html         .lang-dot { background: #e34c26; }
.lang-css          .lang-dot { background: #563d7c; }
.lang-python       .lang-dot { background: #3572A5; }
.lang-java         .lang-dot { background: #b07219; }
.lang-go           .lang-dot { background: #00ADD8; }
.lang-c            .lang-dot { background: #555555; }
.lang-csharp       .lang-dot { background: #178600; }
.lang-ruby         .lang-dot { background: #701516; }
.lang-shell        .lang-dot { background: #89e051; }
.lang-gdscript     .lang-dot { background: #355570; }
.lang-dart         .lang-dot { background: #00B4AB; }
.lang-apex         .lang-dot { background: #1797c0; }

.stars-badge {
  font-size: 0.78rem;
  color: var(--color-text-muted);
  font-weight: 600;
}

.year-badge {
  font-size: 0.78rem;
  color: var(--color-text-light);
  margin-left: auto;
}

.no-results {
  text-align: center;
  color: var(--color-text-muted);
  padding: 3rem 0;
  font-size: 0.95rem;
}

/* ============================================================
   Blog Section
   ============================================================ */
.post-list {
  list-style: none;
}

.post-item {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.875rem 0;
  border-bottom: 1px solid var(--color-border);
}
.post-item:first-child { border-top: 1px solid var(--color-border); }

.post-link {
  font-size: 0.975rem;
  font-weight: 500;
  color: var(--color-text);
  transition: color 0.15s;
  flex: 1;
}
.post-link:hover { color: var(--color-link); }

.blog-more {
  margin-top: 2.5rem;
}

.post-date {
  font-size: 0.825rem;
  color: var(--color-text-light);
  white-space: nowrap;
  flex-shrink: 0;
}

/* ============================================================
   Blog Post / Page Articles
   ============================================================ */
.post-article,
.page-article {
  max-width: 720px;
  margin: 0 auto;
  padding: 3rem 1.5rem 5rem;
}

.post-header,
.page-header {
  margin-bottom: 2.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

.post-title,
.page-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.post-tags { display: flex; gap: 0.4rem; flex-wrap: wrap; }
.tag {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  padding: 0.15rem 0.6rem;
  font-size: 0.775rem;
  color: var(--color-text-muted);
}

/* ============================================================
   Post Content Typography
   ============================================================ */
.post-content,
.page-content {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--color-text);
}

.post-content h1, .post-content h2, .post-content h3,
.post-content h4, .post-content h5, .post-content h6,
.page-content h1, .page-content h2, .page-content h3 {
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.3;
  color: var(--color-text);
}

.post-content h2, .page-content h2 { font-size: 1.4rem; }
.post-content h3, .page-content h3 { font-size: 1.15rem; }

.post-content p, .page-content p { margin-bottom: 1.25rem; }

.post-content a, .page-content a { color: var(--color-link); }
.post-content a:hover, .page-content a:hover { color: var(--color-link-hover); text-decoration: underline; }

.post-content ul, .post-content ol,
.page-content ul, .page-content ol {
  margin: 0 0 1.25rem 1.5rem;
}
.post-content li, .page-content li { margin-bottom: 0.35rem; }

.post-content blockquote, .page-content blockquote {
  border-left: 3px solid var(--color-border);
  padding: 0.5rem 1rem;
  color: var(--color-text-muted);
  margin: 1.25rem 0;
  font-style: italic;
}

.post-content code, .page-content code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.1em 0.35em;
}

.post-content pre, .page-content pre {
  background: #1e1e2e;
  border-radius: var(--radius-md);
  padding: 1.25rem;
  overflow-x: auto;
  margin-bottom: 1.5rem;
}
.post-content pre code, .page-content pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.875rem;
  color: #cdd6f4;
}

.post-content table, .page-content table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
}
.post-content th, .page-content th {
  background: var(--color-surface);
  font-weight: 600;
  padding: 0.6rem 0.75rem;
  text-align: left;
  border: 1px solid var(--color-border);
}
.post-content td, .page-content td {
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--color-border);
}
.post-content tr:nth-child(even) td, .page-content tr:nth-child(even) td {
  background: var(--color-surface);
}

.post-content img, .page-content img {
  border-radius: var(--radius-md);
  margin: 1.5rem auto;
  max-width: 100%;
}

.post-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
}

/* ============================================================
   List Page
   ============================================================ */
.list-page {
  max-width: 720px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}
.list-header { margin-bottom: 2rem; }
.list-header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

/* ============================================================
   Comments
   ============================================================ */
.comments {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 1.5rem 4rem;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 1.5rem;
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}
.footer-links {
  display: flex;
  gap: 1.5rem;
}
.footer-links a {
  color: var(--color-text-muted);
  font-weight: 500;
}
.footer-links a:hover { color: var(--color-text); }
.footer-copy { color: var(--color-text-light); }

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }

  .hero { padding: 4rem 1.25rem 3.5rem; }

  .projects-grid {
    grid-template-columns: 1fr;
  }

  .post-item {
    flex-direction: column;
    gap: 0.25rem;
  }
}

@media (max-width: 480px) {
  :root { --section-padding: 3rem 1.25rem; }

  .hero-name { font-size: 1.75rem; }
  .hero-tagline { font-size: 1rem; }

  .filter-bar { gap: 0.4rem; }
  .filter-btn { padding: 0.3rem 0.8rem; font-size: 0.8rem; }

  .post-article,
  .page-article { padding: 2rem 1.25rem 3rem; }
}

/* ============================================================
   Print
   ============================================================ */
@media print {
  .site-header, .site-footer, .hero-actions,
  .filter-bar, .card-footer { display: none; }
}