:root {
  --ink: #16181d; --muted: #5b6070; --line: #e3e5ea; --bg: #fafaf8; --card: #fff;
  --accent: #e60028; --accent-ink: #fff;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  color: var(--ink); background: var(--bg);
}
* { box-sizing: border-box; }
body { margin: 0; line-height: 1.55; }
main { max-width: 860px; margin: 0 auto; padding: 48px 24px 80px; }
header.top { border-bottom: 1px solid var(--line); background: var(--card); }
header.top div { max-width: 860px; margin: 0 auto; padding: 14px 24px; display: flex; justify-content: space-between; align-items: center; }
header.top a { color: var(--ink); text-decoration: none; font-weight: 600; }
h1 { font-size: clamp(28px, 4vw, 40px); line-height: 1.15; margin: 0 0 12px; letter-spacing: -.01em; }
.lede { font-size: 18px; color: var(--muted); max-width: 60ch; margin: 0 0 28px; }
.btn { display: inline-block; padding: 12px 20px; border-radius: 8px; font-weight: 600; text-decoration: none; border: 1px solid var(--line); color: var(--ink); background: var(--card); }
.btn.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.row { display: flex; gap: 12px; flex-wrap: wrap; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 36px 0; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 20px; }
.card h2 { font-size: 17px; margin: 0 0 6px; }
.card p { margin: 0 0 14px; color: var(--muted); font-size: 15px; }
ol.steps { padding-left: 20px; } ol.steps li { margin: 6px 0; }
.guide h2 { margin-top: 2em; padding-top: .6em; border-top: 1px solid var(--line); }
.guide pre { background: #f1f2f4; padding: 14px; border-radius: 8px; overflow-x: auto; font-size: 13px; }
.guide table { border-collapse: collapse; width: 100%; display: block; overflow-x: auto; }
.guide th, .guide td { border: 1px solid var(--line); padding: 6px 10px; text-align: left; vertical-align: top; }
.btn.disabled { color: var(--muted); cursor: default; background: transparent; }