:root {
  --ink: #172033;
  --muted: #5e6879;
  --line: #d9e0ea;
  --surface: #f6f8fb;
  --accent: #2457a6;
  --accent-soft: #eaf1ff;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.7;
}

.site-shell {
  width: min(100% - 2rem, 960px);
  margin: 0 auto;
}

.site-header {
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, .96);
}

.site-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 4.5rem;
}

.site-title {
  color: var(--ink);
  font-size: 1.1rem;
  font-weight: 750;
  letter-spacing: .01em;
  text-decoration: none;
}

nav { display: flex; flex-wrap: wrap; gap: 1rem; }

a { color: var(--accent); }

nav a { color: var(--muted); font-size: .95rem; text-decoration: none; }
nav a:hover, nav a:focus { color: var(--accent); }

.page-content {
  min-height: calc(100vh - 9rem);
  padding: 4rem 0 5rem;
}

h1, h2, h3 { line-height: 1.25; color: var(--ink); }
h1 { margin: 0 0 1.5rem; font-size: clamp(2rem, 5vw, 3.25rem); letter-spacing: -.025em; }
h2 { margin-top: 2.75rem; font-size: 1.65rem; }
h3 { margin-top: 2rem; font-size: 1.25rem; }

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

blockquote {
  margin-left: 0;
  padding: .25rem 1.25rem;
  border-left: 4px solid var(--accent);
  color: var(--muted);
  background: var(--surface);
}

code { padding: .12rem .3rem; background: var(--surface); border-radius: .25rem; }

pre {
  overflow-x: auto;
  padding: 1rem;
  background: #172033;
  color: #f6f8fb;
  border-radius: .5rem;
}

pre code { padding: 0; background: transparent; }

li { margin: .45rem 0; }

.site-footer {
  padding: 1.25rem 0;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: .9rem;
}

.site-footer a { color: inherit; }

@media (max-width: 640px) {
  .site-header-inner { align-items: flex-start; flex-direction: column; padding: 1rem 0; }
  .page-content { padding-top: 2.5rem; }
}