:root {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #111827;
  background: #f3f7f8;
  color-scheme: light dark;
}

body {
  margin: 0;
  min-height: 100dvh;
  display: grid;
  place-items: center;
  padding: 20px;
  box-sizing: border-box;
}

main { width: min(100%, 380px); display: grid; gap: 14px; }
h1 { margin: 0; font-size: 34px; line-height: 1; }

form {
  display: grid;
  gap: 10px;
  padding: 16px;
  border: 1px solid #d6e1e5;
  border-radius: 10px;
  background: #fff;
  box-shadow: 0 14px 36px rgba(17, 24, 39, .12);
}

label { font-size: 15px; font-weight: 800; }

input {
  min-height: 46px;
  border: 1px solid #d6e1e5;
  border-radius: 8px;
  padding: 0 12px;
  font: inherit;
  font-size: 16px;
  font-weight: 700;
  background: #fff;
  color: inherit;
}

button {
  min-height: 46px;
  border: 1px solid #087a8b;
  border-radius: 8px;
  background: #087a8b;
  color: #fff;
  font: inherit;
  font-size: 17px;
  font-weight: 850;
}

.hint { color: #6b7280; font-size: 14px; font-weight: 650; }
.error { color: #b42318; font-size: 14px; font-weight: 800; }

@media (prefers-color-scheme: dark) {
  :root { color: #e8eef0; background: #0f1719; }
  form { background: #172227; border-color: #2b3a40; box-shadow: 0 14px 36px rgba(0, 0, 0, .45); }
  input { background: #0f1719; border-color: #2b3a40; }
  .hint { color: #9aa9ae; }
  .error { color: #ff9b8f; }
}