:root {
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #e8eef8;
  background: #0c111b;
  font-synthesis: none;
}

* { box-sizing: border-box; }

body {
  min-height: 100vh;
  margin: 0;
  display: grid;
  place-items: center;
  padding: 1.5rem;
  background:
    radial-gradient(circle at 50% 15%, #213353 0, transparent 35rem),
    #0c111b;
}

.card {
  width: min(100%, 25rem);
  padding: 2.5rem;
  border: 1px solid #2a3c5b;
  border-radius: 1.25rem;
  background: rgba(17, 25, 40, 0.94);
  box-shadow: 0 1.5rem 5rem rgba(0, 0, 0, 0.35);
}

.mark { color: #7dd3fc; font-size: 1.4rem; }
h1 { margin: .65rem 0 .5rem; font-size: 1.8rem; letter-spacing: -.025em; }
.message, .hint { color: #a8b5c9; line-height: 1.55; }
.hint { margin: .75rem 0 0; font-size: .82rem; }
form { margin-top: 1.5rem; }
label { display: block; margin-bottom: .5rem; font-size: .9rem; font-weight: 650; }

input, button {
  width: 100%;
  min-height: 3rem;
  border-radius: .65rem;
  font: inherit;
}

input {
  padding: .75rem .9rem;
  border: 1px solid #435575;
  color: inherit;
  background: #0b1321;
}

button {
  margin-top: .9rem;
  padding: .7rem 1rem;
  border: 0;
  color: #07111f;
  background: #7dd3fc;
  font-weight: 750;
  cursor: pointer;
}

button:hover { background: #bae6fd; }
button:focus-visible, input:focus-visible { outline: 3px solid #38bdf8; outline-offset: 2px; }
button:disabled { cursor: wait; opacity: .65; }
.error { min-height: 1.4rem; margin: 1rem 0 0; color: #fda4af; line-height: 1.4; }

@media (prefers-color-scheme: light) {
  :root { color: #172033; background: #eaf0f8; }
  body { background: radial-gradient(circle at 50% 15%, #d7e8fb 0, transparent 35rem), #edf2f8; }
  .card { border-color: #c8d4e3; background: rgba(255, 255, 255, .95); }
  .message, .hint { color: #52617a; }
  input { border-color: #aab8cb; color: #172033; background: #fff; }
}