@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #ffffff;
  --bg-soft:   #f9f9f8;
  --bg-subtle: #f4f4f2;
  --border:    #e8e8e5;
  --border-strong: #d4d4d0;
  --text:      #1a1a1a;
  --text-2:    #4a4a47;
  --text-3:    #8a8a85;
  --accent:    #3d5a80;
  --accent-bg: #eef2f7;
  --accent-soft: #c8d6e8;
  --link:      #3d5a80;
  --code-bg:   #f4f4f2;
  --max:       680px;
  --nav-h:     60px;
}

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

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', -apple-system, sans-serif;
  font-weight: 400;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

/* NAV */
nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: var(--nav-h);
}

.nav-inner {
  max-width: calc(var(--max) + 4rem);
  margin: 0 auto;
  padding: 0 2rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-brand-mark {
  width: 20px;
  height: 20px;
  background: var(--accent);
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.nav-brand-mark svg {
  width: 11px;
  height: 11px;
  fill: #fff;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-links a {
  font-size: 0.82rem;
  font-weight: 450;
  color: var(--text-2);
  text-decoration: none;
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}

.nav-links a:hover {
  background: var(--bg-subtle);
  color: var(--text);
}

.nav-links .nav-ext::after {
  content: ' ↗';
  font-size: 0.7rem;
  opacity: 0.5;
}

/* MAIN */
main {
  max-width: calc(var(--max) + 4rem);
  margin: 0 auto;
  padding: 0 2rem;
}

/* HOME HERO */
.home-hero {
  padding: 4rem 0 3rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 2.5rem;
}

.home-hero-tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-bg);
  border: 1px solid var(--accent-soft);
  padding: 0.25rem 0.65rem;
  border-radius: 4px;
  margin-bottom: 1.25rem;
}

.home-hero h1 {
  font-size: 1.9rem;
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.25;
  color: var(--text);
  margin-bottom: 1rem;
  max-width: 520px;
}

.home-hero p {
  font-size: 0.95rem;
  color: var(--text-2);
  max-width: 500px;
  line-height: 1.7;
}

/* POST LIST */
.post-list { list-style: none; }

.post-item {
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--border);
  display: grid;
  grid-template-columns: 100px 1fr;
  gap: 0 2rem;
  align-items: start;
}

.post-item:last-child { border-bottom: none; }

.post-date {
  font-size: 0.75rem;
  color: var(--text-3);
  padding-top: 0.25rem;
  white-space: nowrap;
}

.post-tags {
  display: flex;
  gap: 0.4rem;
  margin-bottom: 0.5rem;
  flex-wrap: wrap;
}

.post-tag {
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-bg);
  border: 1px solid var(--accent-soft);
  padding: 0.15rem 0.45rem;
  border-radius: 4px;
}

.post-item h2 {
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.4;
  margin-bottom: 0.4rem;
}

.post-item h2 a {
  color: var(--text);
  text-decoration: none;
  transition: color 0.15s;
}

.post-item h2 a:hover { color: var(--accent); }

.post-excerpt {
  font-size: 0.875rem;
  color: var(--text-2);
  line-height: 1.65;
}

/* POST PAGE */
.post-header {
  padding: 3.5rem 0 2.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 2.75rem;
}

.post-header-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.post-header-date {
  font-size: 0.8rem;
  color: var(--text-3);
}

.post-header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.25;
  color: var(--text);
  max-width: 560px;
}

/* POST CONTENT */
.post-content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-2);
  padding-bottom: 4rem;
}

.post-content > * + * { margin-top: 1.4rem; }

.post-content h2 {
  font-size: 1.2rem;
  font-weight: 650;
  letter-spacing: -0.015em;
  color: var(--text);
  margin-top: 2.75rem;
  margin-bottom: 0.75rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--border);
}

.post-content h3 {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

.post-content p { color: var(--text-2); }
.post-content strong { color: var(--text); font-weight: 600; }
.post-content em { font-style: italic; }

.post-content a {
  color: var(--link);
  text-decoration: underline;
  text-decoration-color: var(--accent-soft);
  text-underline-offset: 2px;
  transition: text-decoration-color 0.15s;
}
.post-content a:hover { text-decoration-color: var(--link); }

.post-content ul,
.post-content ol {
  padding-left: 1.4rem;
  color: var(--text-2);
}
.post-content li { margin-bottom: 0.3rem; }

.post-content blockquote {
  border-left: 3px solid var(--border-strong);
  padding: 0.25rem 0 0.25rem 1.25rem;
  color: var(--text-3);
  font-style: italic;
}

.post-content code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.82rem;
  background: var(--code-bg);
  border: 1px solid var(--border);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  color: var(--text);
}

.post-content pre {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  margin: 1.75rem 0;
}

.post-content pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.83rem;
  color: var(--text);
  line-height: 1.7;
}

.post-content table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
  margin: 1.75rem 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
}

.post-content thead { background: var(--bg-subtle); }

.post-content th {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--text-3);
  padding: 0.65rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.post-content td {
  padding: 0.65rem 1rem;
  color: var(--text-2);
  border-bottom: 1px solid var(--border);
}
.post-content tr:last-child td { border-bottom: none; }
.post-content tbody tr:hover { background: var(--bg-soft); }

.post-content hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2.5rem 0;
}

.post-nav {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  gap: 1rem;
}
.post-nav a { color: var(--text-3); text-decoration: none; transition: color 0.15s; }
.post-nav a:hover { color: var(--text); }

/* ABOUT */
.about-wrap { padding: 3.5rem 0 5rem; }

.about-wrap h1 {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.about-wrap h2 {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 2.5rem 0 0.75rem;
}

.about-wrap p {
  font-size: 0.95rem;
  color: var(--text-2);
  line-height: 1.75;
  margin-bottom: 1rem;
}

.about-wrap ul {
  font-size: 0.95rem;
  color: var(--text-2);
  padding-left: 1.25rem;
  margin-bottom: 1rem;
}
.about-wrap li { margin-bottom: 0.3rem; }

/* FOOTER */
footer {
  border-top: 1px solid var(--border);
  padding: 1.75rem 2rem;
  background: var(--bg-soft);
}

.footer-inner {
  max-width: calc(var(--max) + 4rem);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

footer p { font-size: 0.78rem; color: var(--text-3); }
footer a { color: var(--text-3); text-decoration: none; transition: color 0.15s; }
footer a:hover { color: var(--text); }

@media (max-width: 640px) {
  .post-item { grid-template-columns: 1fr; gap: 0.4rem; }
  .post-header h1 { font-size: 1.4rem; }
  .home-hero h1 { font-size: 1.5rem; }
  .nav-links .nav-ext { display: none; }
}