body {
    font-family: 'Arial', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f4f4f4;
    margin: 0;
  }
  
  #mainDiv {
    background-color: #fff;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    text-align: center;
  }
  
  h1 {
    color: #333;
    margin-bottom: 20px;
  }
  
  fieldset {
    border: 0;
    width: 100%;
    margin-bottom: 15px;
    display: flex;
    flex-direction: column;
    align-items: center;
  }
  
  label {
    margin-bottom: 5px;
    font-weight: bold;
    color: #333;
    text-align: left;
    width: fit-content;
  }
  
  input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    box-sizing: border-box;
    margin-bottom: 15px;
    font-size: 16px;
    text-align: left;
  }
  
  button {
    background-color: #4CAF50;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
  }
  
  button:hover {
    background-color: #45a049;
  }
  
  #alertBox {
    color: red;
    margin-top: 10px;
    padding: 10px;
    border: 1px solid red;
    border-radius: 5px;
    display: none;
    text-align: center; /* Alertbox metnini merkezliyoruz */
  }
  
  @media (max-width: 500px) {
    #mainDiv {
      padding: 20px;
    }
  }