body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: linear-gradient(135deg, #0d47a1, #1976d2);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.login-container {
  width: 100%;
  max-width: 380px;
  padding: 1rem;
}

.card {
  background: white;
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: 0 4px 20px rgba(0,0,0,0.2);
  text-align: center;
}

h1 {
  margin-bottom: 1.5rem;
  font-size: clamp(1.6rem, 4vw, 2.2rem);
}

input {
  width: 100%;
  padding: 0.8rem;
  margin: 0.7rem 0;
  border-radius: 0.5rem;
  border: 1px solid #ccc;
  font-size: 1rem;
}

button {
  width: 100%;
  padding: 0.8rem;
  font-size: 1.1rem;
  background: #1976d2;
  border: none;
  color: white;
  margin-top: 1rem;
  border-radius: 0.5rem;
  cursor: pointer;
}

button:hover {
  background: #1565c0;
}

.error {
  color: red;
  margin-top: 1rem;
  height: 1rem;
}