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

:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --border: #2a2d3a;
  --accent: #7c6af7;
  --accent-hover: #9d8fff;
  --text: #e2e4f0;
  --text-muted: #8a8fa8;
  --karpathy: #5b9bd5;
  --anthropic: #e5825a;
  --news: #4caf7d;
  --font: 'Inter', 'Noto Sans KR', system-ui, sans-serif;
  --max-w: 760px;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  font-size: 16px;
}

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

/* ─── Layout ────────────────────────────────────────────────── */
.site-header {
  border-bottom: 1px solid var(--border);
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  background: var(--bg);
  z-index: 100;
}

.site-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.02em;
}

.site-title span { color: var(--accent); }

nav a {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-left: 20px;
  transition: color 0.2s;
}
nav a:hover { color: var(--text); text-decoration: none; }

main { max-width: var(--max-w); margin: 0 auto; padding: 48px 24px; }

footer {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 32px 24px;
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ─── AdSense Zones ─────────────────────────────────────────── */
.ad-leaderboard {
  width: 100%; max-width: 728px; height: 90px;
  background: var(--surface);
  border: 1px dashed var(--border);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-muted); font-size: 0.75rem;
  margin: 0 auto 40px;
  border-radius: 4px;
}

.ad-in-article {
  width: 100%; max-width: 336px; height: 280px;
  background: var(--surface);
  border: 1px dashed var(--border);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-muted); font-size: 0.75rem;
  margin: 32px auto;
  border-radius: 4px;
}

.ad-skyscraper {
  width: 160px; height: 600px;
  background: var(--surface);
  border: 1px dashed var(--border);
  display: flex; align-items: center; justify-content: center;
  color: var(--text-muted); font-size: 0.75rem;
  border-radius: 4px;
  flex-shrink: 0;
}

/* ─── Home — Post List ──────────────────────────────────────── */
.hero {
  text-align: center;
  padding: 60px 0 48px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 48px;
}

.hero h1 {
  font-size: 2rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  margin-bottom: 12px;
}

.hero p {
  color: var(--text-muted);
  font-size: 1rem;
  max-width: 480px;
  margin: 0 auto 24px;
}

.tag-filter {
  display: flex;
  gap: 8px;
  justify-content: center;
  flex-wrap: wrap;
}

.tag-btn {
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-muted);
  font-size: 0.82rem;
  cursor: pointer;
  transition: all 0.2s;
}
.tag-btn:hover, .tag-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.tag-btn.karpathy.active  { background: var(--karpathy); border-color: var(--karpathy); }
.tag-btn.anthropic.active { background: var(--anthropic); border-color: var(--anthropic); }
.tag-btn.news.active      { background: var(--news); border-color: var(--news); }

.post-grid { display: grid; gap: 24px; }

.post-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  transition: border-color 0.2s, transform 0.2s;
}
.post-card:hover { border-color: var(--accent); transform: translateY(-2px); }

.post-card-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.post-tag {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.post-tag.karpathy  { background: #1e3a52; color: var(--karpathy); }
.post-tag.anthropic { background: #3d2318; color: var(--anthropic); }
.post-tag.news      { background: #1a3328; color: var(--news); }

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

.post-card h2 { font-size: 1.1rem; font-weight: 700; margin-bottom: 8px; letter-spacing: -0.02em; }
.post-card p  { font-size: 0.9rem; color: var(--text-muted); }

.post-card a { color: inherit; }
.post-card a:hover { text-decoration: none; }

.lang-badge {
  margin-left: auto;
  font-size: 0.72rem;
  color: var(--text-muted);
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: 4px;
}

/* ─── Post Page ─────────────────────────────────────────────── */
.post-layout {
  display: grid;
  grid-template-columns: 1fr 160px;
  gap: 40px;
  align-items: start;
}

@media (max-width: 680px) {
  .post-layout { grid-template-columns: 1fr; }
  .ad-skyscraper { display: none; }
}

.post-header { margin-bottom: 36px; }

.post-header .post-tag { display: inline-block; margin-bottom: 16px; }

.post-header h1 {
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1.3;
  margin-bottom: 16px;
}

.post-header .byline {
  color: var(--text-muted);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 16px;
}

.lang-toggle {
  display: flex;
  gap: 4px;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  width: fit-content;
  margin-bottom: 32px;
}
.lang-toggle button {
  padding: 6px 16px;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.15s;
}
.lang-toggle button.active { background: var(--accent); color: #fff; }

.post-hero-img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
  border-radius: 12px;
  margin-bottom: 36px;
  background: var(--surface);
}

.post-content { font-size: 1rem; line-height: 1.85; }
.post-content h2 { font-size: 1.25rem; font-weight: 700; margin: 36px 0 12px; letter-spacing: -0.02em; }
.post-content h3 { font-size: 1.05rem; font-weight: 600; margin: 24px 0 8px; }
.post-content p  { margin-bottom: 20px; }
.post-content ul, .post-content ol { margin: 0 0 20px 24px; }
.post-content li { margin-bottom: 6px; }
.post-content code {
  background: var(--surface);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.88em;
  color: var(--accent-hover);
}
.post-content pre {
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 20px;
  border-radius: 8px;
  overflow-x: auto;
  margin-bottom: 20px;
}
.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 16px;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 60px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}
.post-nav a {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  font-size: 0.88rem;
  color: var(--text);
}
.post-nav a:hover { border-color: var(--accent); text-decoration: none; }
.post-nav .label { font-size: 0.72rem; color: var(--text-muted); margin-bottom: 6px; }