body{
    margin: 0;
    padding: 0;
}

.leftmenu
{
    width: 20%;
    position: absolute;
    bottom: 0;
    top: 0;
    background-color: black;
}
.doc
{
    width: 80%;
    height: 100%;
    left: 20%;
    position: absolute; 
    border: none;
    background-color: white;
}
.leftbtn
{
    width: 99%;
    height: 50px;
    background-color: black;
    border: none;
    color: white;
}
.leftbtn:hover
{
    box-shadow: 0px 0px 10px white;
    background-color: white;
    color: black;
}
.box
{
    width: 80%;
    height: auto;
    background-color: aliceblue;
    margin: 20px;
    padding: 20px;
    border-radius: 10px;
    color:rgb(58, 58, 58);
}