:root {
  --navy: #0f1f4d;
  --sky: #38bdf8;
  --ink: #1e293b;
  --muted: #5b6577;
  --line: #d9e1ec;
  --bg: #f4f7fb;
  --card: #ffffff;
  --danger: #c62828;
  --danger-ink: #ffffff;
  --ok: #047857;
}
@media (prefers-color-scheme: dark) {
  :root {
    --ink: #e6ebf3;
    --muted: #a3adbd;
    --line: #2a3550;
    --bg: #0b1430;
    --card: #121d3f;
    --danger: #ef5350;
    --ok: #34d399;
  }
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  padding: 0 16px 48px;
}
header {
  background: var(--navy);
  color: #fff;
  margin: 0 -16px 28px;
  padding: 18px 16px;
}
header .brand { max-width: 560px; margin: 0 auto; font-weight: 700; letter-spacing: 0.02em; }
main { max-width: 560px; margin: 0 auto; }
h1 { font-size: 1.6rem; line-height: 1.25; margin: 0 0 12px; text-wrap: balance; }
p { margin: 0 0 14px; }
.muted { color: var(--muted); font-size: 0.94rem; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px;
  margin: 18px 0;
}
ul { margin: 0 0 14px; padding-left: 20px; }
li { margin: 4px 0; }
label { display: block; font-weight: 600; margin-bottom: 6px; }
input[type="email"], input[type="text"] {
  width: 100%;
  font: inherit;
  padding: 12px 14px;
  border: 1.5px solid var(--line);
  border-radius: 8px;
  background: var(--bg);
  color: var(--ink);
}
input:focus-visible, button:focus-visible, a:focus-visible {
  outline: 3px solid var(--sky);
  outline-offset: 2px;
}
button {
  margin-top: 14px;
  font: inherit;
  font-weight: 700;
  border: 0;
  border-radius: 999px;
  padding: 12px 22px;
  cursor: pointer;
  background: var(--navy);
  color: #fff;
}
@media (prefers-color-scheme: dark) { button { background: var(--sky); color: var(--navy); } }
button.danger { background: var(--danger); color: var(--danger-ink); }
button[disabled] { opacity: 0.55; cursor: not-allowed; }
.status { margin-top: 16px; padding: 14px 16px; border-radius: 8px; border: 1px solid var(--line); }
.status.ok { border-color: var(--ok); }
.status.err { border-color: var(--danger); }
.hidden { display: none; }
a { color: inherit; }
.hint { margin-top: 8px; }