:root {
  --ink: #1d2433;
  --muted: #5b6475;
  --line: #d6dbe4;
  --ground: #f4f6f9;
  --card: #ffffff;
  --accent: #1f4e8c;
  --accent-ink: #ffffff;
  --error: #a3261c;
  color-scheme: light;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

.shell {
  max-width: 28rem;
  margin: 0 auto;
  padding: 2.5rem 1rem;
}

.brand h1 { margin: 0; font-size: 1.6rem; }
.brand p { margin: 0 0 1.5rem; color: var(--muted); }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 1.25rem;
}

.card h2 { margin: 0 0 1rem; font-size: 1.15rem; }

label { display: block; margin: 0.75rem 0 0.25rem; font-weight: 600; font-size: 0.9rem; }

input {
  width: 100%;
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  font: inherit;
}

input:focus, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

button {
  margin-top: 1.25rem;
  width: 100%;
  padding: 0.7rem;
  border: 0;
  border-radius: 6px;
  background: var(--accent);
  color: var(--accent-ink);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

button:disabled { opacity: 0.6; cursor: wait; }

button.secondary { background: transparent; color: var(--accent); border: 1px solid var(--accent); }

.muted { color: var(--muted); }
.error { color: var(--error); margin: 0.75rem 0 0; }
[hidden] { display: none !important; }