:root {
  --bg: #ffffff; --fg: #14171c; --muted: #5d6470; --line: #e7e9ee; --soft: #f5f6f8;
  --accent: #3b5bdb; --accent-fg: #ffffff;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #0f1115; --fg: #e8eaee; --muted: #9aa1ad; --line: #252a33; --soft: #161a20; --accent: #7c95ff; --accent-fg: #0f1115; }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
a { color: var(--accent); }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 20px; }
header { border-bottom: 1px solid var(--line); }
header .wrap { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--fg); text-decoration: none; font-weight: 650; font-size: 18px; letter-spacing: .2px; }
.brand svg { width: 26px; height: 26px; }
nav a { color: var(--muted); text-decoration: none; margin-left: 22px; font-size: 15px; }
nav a:hover { color: var(--fg); }
.hero { padding-top: 88px; padding-bottom: 64px; }
.hero h1 { font-size: clamp(32px, 5vw, 48px); line-height: 1.12; margin: 0 0 18px; letter-spacing: -.5px; max-width: 760px; }
.hero p { font-size: 19px; color: var(--muted); max-width: 640px; margin: 0; }
.notice { display: inline-block; margin-top: 28px; padding: 6px 12px; border: 1px solid var(--line); border-radius: 999px; font-size: 14px; color: var(--muted); background: var(--soft); }
section { padding: 48px 0; border-top: 1px solid var(--line); }
section h2 { font-size: 22px; margin: 0 0 24px; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; }
.card { background: var(--soft); border: 1px solid var(--line); border-radius: 10px; padding: 22px; }
.card h3 { margin: 0 0 8px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
.prose { max-width: 680px; }
.prose p { color: var(--muted); }
footer { border-top: 1px solid var(--line); padding: 28px 0 40px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px; }