:root {
  --bg: #fbfbf9;
  --surface: #ffffff;
  --text: #1c1f1d;
  --muted: #5c635f;
  --accent: #2e7d5b;
  --accent-soft: #e6f2ec;
  --border: #e7e8e4;
  --radius: 14px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141615;
    --surface: #1c1f1d;
    --text: #eef0ed;
    --muted: #9aa39d;
    --accent: #6bc79c;
    --accent-soft: #1e2b25;
    --border: #2a2e2b;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo",
    "Pretendard", "Segoe UI", "Malgun Gothic", Roboto, sans-serif;
  line-height: 1.72;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

.wrap { max-width: 680px; margin: 0 auto; padding: clamp(1.5rem, 4vw, 3rem) 1.25rem 4rem; }

header.site {
  display: flex; align-items: center; gap: .7rem;
  padding-bottom: 1.4rem; margin-bottom: 1.8rem;
  border-bottom: 1px solid var(--border);
}
.logo {
  width: 40px; height: 40px; border-radius: 11px;
  background: var(--accent); color: #fff;
  display: grid; place-items: center;
  font-weight: 800; font-size: 20px; letter-spacing: -.02em;
}
.site h1 { font-size: 1.05rem; margin: 0; font-weight: 700; letter-spacing: -.01em; }
.site .sub { color: var(--muted); font-size: .85rem; margin-top: 1px; }

h1.doc { font-size: clamp(1.5rem, 5vw, 1.9rem); letter-spacing: -.02em; margin: 0 0 .3rem; }
.updated { color: var(--muted); font-size: .85rem; margin: 0 0 2rem; }

h2 {
  font-size: 1.12rem; letter-spacing: -.01em; margin: 2.2rem 0 .6rem;
  padding-left: .7rem; border-left: 3px solid var(--accent);
}
p { margin: 0 0 1rem; }
strong { font-weight: 700; }
a { color: var(--accent); text-underline-offset: 3px; }

.lead {
  background: var(--accent-soft); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.1rem 1.2rem; margin: 0 0 2rem;
  color: var(--text);
}

.cards { display: grid; gap: 1rem; margin-top: 1.6rem; }
.card {
  display: block; text-decoration: none; color: inherit;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.2rem 1.3rem;
  transition: border-color .18s ease, transform .18s ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card .t { font-weight: 700; font-size: 1.05rem; }
.card .d { color: var(--muted); font-size: .9rem; margin-top: .2rem; }

footer {
  margin-top: 3rem; padding-top: 1.4rem; border-top: 1px solid var(--border);
  color: var(--muted); font-size: .85rem;
}
footer a { font-weight: 600; }
.back { display: inline-block; margin-bottom: 1.6rem; color: var(--muted); font-size: .9rem; text-decoration: none; }
.back:hover { color: var(--accent); }