:root { --ink:#15171a; --muted:#5c6670; --line:#e6e9ec; --accent:#1f5f8b;
  --bg:#fff; --panel:#f7f8f9; }
@media (prefers-color-scheme: dark) {
  :root { --ink:#e8eaed; --muted:#9aa3ad; --line:#2a2f36; --accent:#6fb3dd;
    --bg:#15171a; --panel:#1c1f24; }
}
* { box-sizing:border-box; }
body { margin:0; background:var(--bg); color:var(--ink);
  font:16px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif; }
.wrap { max-width:640px; margin:0 auto; padding:0 24px; }
header { border-bottom:1px solid var(--line); padding:20px 0; }
header .wrap { display:flex; align-items:center; justify-content:space-between; gap:20px; }
.logo { font-weight:650; letter-spacing:-.02em; font-size:19px; color:var(--ink); text-decoration:none; }
nav a { color:var(--muted); text-decoration:none; margin-left:20px; font-size:15px; }
nav a:hover { color:var(--ink); }
h1 { font-size:34px; line-height:1.2; letter-spacing:-.02em; margin:56px 0 14px; }
h2 { font-size:15px; text-transform:uppercase; letter-spacing:.07em; color:var(--muted);
  margin:44px 0 16px; font-weight:600; }
p { margin:0 0 18px; }
.lead { font-size:18px; color:var(--muted); margin:0 0 32px; }
a { color:var(--accent); }
.panel { background:var(--panel); border:1px solid var(--line); border-radius:10px;
  padding:24px; margin:0 0 20px; }
.form { display:flex; gap:10px; flex-wrap:wrap; }
.form input { flex:1 1 240px; padding:11px 13px; border:1px solid var(--line);
  border-radius:7px; background:var(--bg); color:var(--ink); font-size:15px; }
.form button { padding:11px 22px; border:0; border-radius:7px; background:var(--accent);
  color:#fff; font-size:15px; cursor:pointer; }
.note { font-size:13px; color:var(--muted); margin:12px 0 0; }
ul { color:var(--muted); padding-left:22px; margin:0 0 18px; }
li { margin-bottom:9px; }
.center { text-align:center; }
footer { border-top:1px solid var(--line); margin-top:64px; padding:24px 0 44px;
  color:var(--muted); font-size:14px; display:flex; justify-content:space-between; flex-wrap:wrap; gap:12px; }