:root {
  --canvas: #f4f6f9;
  --surface: #ffffff;
  --ink: #202631;
  --ink-muted: #5b6575;
  --border: #dde2ea;
  --accent: #245fb4;
  --accent-hover: #1c4b91;
  --danger: #b42323;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --canvas: #0f1215;
    --surface: #171b20;
    --ink: #e8ecf1;
    --ink-muted: #9aa4b2;
    --border: #2a3038;
    --accent: #6ba3e8;
    --accent-hover: #8db8ee;
    --danger: #f07a7a;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 16px;
  background: var(--canvas);
  color: var(--ink);
  font-family: Inter, system-ui, sans-serif;
}

.card {
  width: 100%;
  max-width: 360px;
  padding: 40px 32px 32px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--surface);
  text-align: center;
  box-shadow: 0 8px 30px rgb(15 23 42 / 0.06);
}

.logo { display: block; margin: 0 auto 12px; }

.name {
  margin: 0 0 4px;
  font-family: 'Plus Jakarta Sans', Inter, sans-serif;
  font-size: 1.5rem;
  font-weight: 700;
}

.hint { margin: 0 0 24px; color: var(--ink-muted); font-size: 0.9rem; }

form { display: flex; flex-direction: column; gap: 10px; text-align: start; }

.label { font-size: 0.85rem; font-weight: 500; color: var(--ink-muted); }

input {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
  color: var(--ink);
  font: inherit;
}

input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: transparent; }
input[aria-invalid='true'] { border-color: var(--danger); }

.error { margin: 0; color: var(--danger); font-size: 0.85rem; }

button {
  margin-top: 6px;
  padding: 10px 12px;
  border: 0;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

button:hover { background: var(--accent-hover); }
button:disabled { opacity: 0.6; cursor: progress; }