body {
      background: linear-gradient(135deg, #002b36, #004d40);
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100vh;
      color: #fff;
      font-family: 'Segoe UI', sans-serif;
    }

    .login-card {
      background: #1b1f23;
      padding: 40px;
      border-radius: 15px;
      box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
      width: 100%;
      max-width: 400px;
      text-align: center;
    }

    .login-card img {
      width: 140px;
      margin-bottom: 15px;
    }

    .login-card h3 {
      color: #00bcd4;
      font-weight: 600;
      margin-bottom: 25px;
    }

    .form-control {
      background: #2c3036;
      border: none;
      color: #fff;
    }

    .form-control:focus {
      box-shadow: 0 0 5px #00bcd4;
      background: #333;
      color: #fff;
    }

    .btn-primary {
      background-color: #00bcd4;
      border: none;
      font-weight: 600;
    }

    .btn-primary:hover {
      background-color: #0097a7;
    }

    .alert {
      background: #c62828;
      color: white;
      border: none;
      font-weight: 500;
    }

    footer {
      position: fixed;
      bottom: 15px;
      text-align: center;
      width: 100%;
      color: #aaa;
      font-size: 0.9em;
    }