body {
      background: linear-gradient(135deg, #74ABE2, #5563DE);
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      font-family: Arial, sans-serif;
    }

    nav {
      display: flex;
    }
    nav a {
      margin: 0 10px;
      color: lime;
      font-weight: bold;
      text-decoration: none;
    }

    .card {
      border: none;
      border-radius: 1rem;
      box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
      background-color: #fff;
    }

    .form-label {
      font-weight: 600;
      color: #333;
    }

    .btn-primary {
      background: #5563DE;
      border: none;
      transition: all 0.3s ease;
    }

    .btn-primary:hover {
      background: #3742fa;
      transform: translateY(-2px);
    }

    h1 {
      font-weight: 700;
      color: #343a40;
      text-align: center;
      margin-bottom: 1rem;
    }

    .form-check-label {
      font-size: 0.95rem;
    }

    .valid-feedback, .invalid-feedback {
      font-size: 0.9rem;
    }