/* Learn Blog theme — clean, readable, minimal */
:root {
  --bg: #ffffff;
  --surface: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --border: #e5e7eb;
  --hover: #f8fafc;
  --link: #0f172a;
  --btn-bg: #0f172a;
  --btn-fg: #ffffff;
  --btn-border: #0b1220;
  --chip: #f3f4f6;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0b0b;
    --surface: #101010;
    --text: #e6e6e6;
    --muted: #a1a1aa;
    --border: #262626;
    --hover: #141414;
    --link: #e6e6e6;
    --btn-bg: #ffffff;
    --btn-fg: #0b0b0b;
    --btn-border: #e6e6e6;
    --chip: #141414;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.75;
}

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 2px; }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 32px;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  padding: 24px 0 16px;
  border-bottom: 1px solid var(--border);
}

.title {
  margin: 0;
  font-size: 34px;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

.subtitle { color: var(--muted); margin-top: 6px; }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
  margin-top: 20px;
}

.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  transition: background-color 0.2s ease, border-color 0.2s ease, transform 0.15s ease, box-shadow 0.2s ease;
}

.card h3 { margin: 0 0 6px; font-size: 18px; letter-spacing: -0.01em; }
.card p { margin: 0; color: var(--muted); font-size: 14px; }

.card:hover {
  background: var(--hover);
  border-color: color-mix(in srgb, var(--border) 60%, var(--text) 40%);
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.06);
}

.cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  background: var(--btn-bg);
  color: var(--btn-fg);
  border: 1px solid var(--btn-border);
  padding: 10px 14px;
  border-radius: 999px;
  font-weight: 600;
  text-decoration: none;
  transition: background-color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease, transform 0.15s ease;
}

.cta:hover { background: color-mix(in srgb, var(--btn-bg) 85%, white 15%); transform: translateY(-1px); }

.cta.secondary {
  background: transparent;
  color: var(--link);
  border: 1px solid var(--border);
}

.cta.secondary:hover { background: var(--hover); }

main article { max-width: 760px; margin: 24px auto 0; padding: 0; }

article {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px;
}

@media (min-width: 1024px) { article { padding: 32px; } }

article h1 { margin: 0 0 8px; font-size: 28px; letter-spacing: -0.01em; }
article h2 { margin-top: 22px; font-size: 20px; color: var(--muted); }
article p { margin: 12px 0; }
article ul, article ol { padding-left: 22px; margin: 10px 0; }
article li { margin: 6px 0; }

article blockquote {
  margin: 12px 0;
  padding: 8px 12px;
  border-left: 3px solid var(--border);
  color: var(--muted);
  background: var(--hover);
  border-radius: 8px;
}

.meta { display: flex; gap: 8px; flex-wrap: wrap; margin: 8px 0 0; }

.pill {
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 2px 10px;
  color: var(--muted);
  background: var(--chip);
  font-size: 12px;
}

footer {
  border-top: 1px solid var(--border);
  margin-top: 28px;
  padding-top: 16px;
  color: var(--muted);
  font-size: 12px;
}

.cta:focus-visible, .card:focus-visible, a:focus-visible {
  outline: 2px solid var(--link);
  outline-offset: 2px;
  text-decoration: none;
}