* {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: 'Poppins', sans-serif;
      background: linear-gradient(180deg, #fff, #17a2b8);
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100vh;
    }

    .login-container {
      background-color: #fff;
      padding: 40px 30px;
      border-radius: 12px;
      box-shadow: 0 10px 30px rgba(23, 162, 184, 0.1);
      width: 100%;
      max-width: 360px;
      animation: fadeIn 0.8s ease;
    }

    .login-container h2 {
      text-align: center;
      margin-bottom: 24px;
      font-weight: 600;
      color: #333;
    }

    #login-form input {
      width: 100%;
      padding: 12px 16px;
      margin: 10px 0;
      border: 1px solid #ddd;
      border-radius: 8px;
      transition: border 0.3s;
    }

    #login-form input:focus {
      outline: none;
      border-color: #17a2b8;
      box-shadow: 0 0 0 3px rgba(23, 162, 184, 0.18);
    }

    #login-form button {
      width: 100%;
      padding: 12px;
      background-color: #17a2b8;
      color: white;
      border: none;
      border-radius: 8px;
      cursor: pointer;
      font-weight: 600;
      font-size: 16px;
      margin-top: 12px;
      transition: background-color 0.3s ease;
    }

    #login-form button:hover {
      background-color: #179cb8;
    }

    #error-message {
      color: red;
      margin-top: 12px;
      text-align: center;
      font-size: 14px;
    }

    .register-link {
      text-align: center;
      margin-top: 18px;
      display: block;
      font-size: 14px;
    }

    .register-link a {
      color: #17a2b8;
      text-decoration: none;
      font-weight: 500;
    }

    .register-link a:hover {
      text-decoration: underline;
    }

    @keyframes fadeIn {
      from {
        opacity: 0;
        transform: translateY(20px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    @media (max-width: 400px) {
      .login-container {
        padding: 30px 20px;
      }
    }