main_pages.css

    div{
        border: solid red 0px;
    }

/* layout of header and body */

    header{

        padding-bottom:20px;
        border: solid blue 0px;
    }

    body{
        margin: 100px;
        margin-top: 50px;
        border: solid green 0px;

        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
 
 

 
        /* not sure it if should be aligned to center */
    }


    p{
        margin-left: 50px;
        margin-right: 50px;
    }



    a{
        color: black;
        text-decoration: underline;
        text-underline-offset: 2px;
        text-decoration-color: gray;
    }
    a:hover{
        color: darkblue;
    }

    .title{
        border: solid purple 0px;
        border-bottom: solid lightgray 1px;
        padding-bottom: 5px;
        margin-bottom: 0px;
        margin-top: 40px;
        color: #222;
        
    }



/* links to each topic */
    .topic-group {
        /* the padding specifies how far the buttons are spaced vertically */

        padding-top: 20px;
        
        position: absolute;
        left: 25%;
        padding-left: 5px;
        padding-right: 5px;
        text-align: center;
    }
    .topic-link {
        /*
        box-shadow: 0px 0px 4px 0 rgba(0,0,0,.2);
        border-radius: 20px;
        background-color:lightblue;
        transition: 0.3s;
        font-size: 13px;
        text-decoration: none;
        color: black;
        padding: 15px;
        margin-right: 20px;
        margin-left: 20px;
        */
        float: left;
        width: 150px;
        padding: 10px;
    }
    
    .topic-link:hover {
    box-shadow: 5px 5px 8px 0 rgba(0,0,0,0.2);
    }
      

/* links to Topics, About, Feedback etc. */
    .tab{
        text-decoration: none;
        color: black;
        padding-bottom: 20px;
        padding-right: 20px;
        width: 50px;
    }
    .tab:hover{
        color: gray
    }
    .tab.active{
        color: blue
    }

/* styl of titles for the pages */