* { box-sizing: border-box; }
html, body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: linear-gradient(135deg, #1e3a8a 0%, #6366f1 100%);
  color: #1f2937;
}
body {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}
.card {
  background: #fff;
  border-radius: 14px;
  box-shadow: 0 20px 50px rgba(0, 0, 0, .25);
  padding: 36px 32px;
  width: 100%;
  max-width: 380px;
}
h1 {
  margin: 0 0 6px;
  font-size: 22px;
  font-weight: 600;
}
.subtitle {
  margin: 0 0 22px;
  color: #6b7280;
  font-size: 14px;
}
.error {
  background: #fef2f2;
  border: 1px solid #fecaca;
  color: #991b1b;
  padding: 10px 12px;
  border-radius: 8px;
  font-size: 13px;
  margin-bottom: 16px;
}
form label {
  display: block;
  margin-bottom: 14px;
}
form label span {
  display: block;
  font-size: 12px;
  color: #4b5563;
  margin-bottom: 6px;
  font-weight: 500;
}
input[type="text"], input[type="password"] {
  width: 100%;
  padding: 10px 12px;
  font-size: 14px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  outline: none;
  transition: border-color .15s, box-shadow .15s;
}
input:focus {
  border-color: #6366f1;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, .15);
}
button[type="submit"] {
  width: 100%;
  margin-top: 8px;
  padding: 11px 14px;
  background: #4f46e5;
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background .15s;
}
button[type="submit"]:hover {
  background: #4338ca;
}
.hint {
  margin: 18px 0 0;
  text-align: center;
  color: #9ca3af;
  font-size: 12px;
}