16.css

body {
    background-color: #F5D6C6;
    margin: auto;
    margin-top: 70px;
    width: 60%; 
    padding: 10px;
    text-align: center;
}

.div1 h1, .div2 h1, .div3 h1 {
    padding-top: 20px;

}

.div1-btn, .div2-btn, .div3-btn {
    margin: auto;
    width: 60%; 
    padding: 10px;
    text-align: center;
}

.div1 button, .div2 button, .div3 button {
    background-color: #4CAF50; /* Green background /
    border: 1px solid green; /* Green border */
    border: 2px solid #4CAF50; /* Green */
    color: white; /* White text */
    padding: 10px 24px; /* Some padding */
    cursor: pointer; /* Pointer/hand icon */
    float: center; /* Float the buttons side by side */
    position: relative;
  }
  
  /* Clear floats (clearfix hack) */
  .div1:after, .div2:after, .div3:after{
    content: "";
    clear: both;
    display: table;
  }
  
  .div1 button:not(:last-child), .div2 button:not(:last-child), .div3 button:not(:last-child){
    border-right: none; /* Prevent double borders */
  }
  
  /* Add a background color on hover */
  .div1 button:hover, .div2 button:hover, .div3 button:hover {
    background-color: #3e8e41;
  }

  /* #ok1 {
    background-color: #3e8e41;
    box-shadow: 0 12px 16px 0 rgba(0,0,0,0.24), 0 17px 50px 0 rgba(0,0,0,0.19);
  } */
  
  .div2 {
      visibility: hidden;
  }

  .div3 {
    visibility: hidden;
  }

  .active {
    pointer-events: none;
    cursor: default;
   }

   a:link {
    color:black;
    background-color: transparent;
    text-decoration: none;
  }
  
   a:visited {
    color:black;
    text-decoration: none;
  }
  
   a:hover {
    color:black;
    text-decoration: none;
  }
  
   a:active {
    color:black;
    text-decoration: underline;
   }