* {
    box-sizing: border-box;
  }
  body{
    background-color:rgb(232, 228, 228);
    margin: 0;
  }
  header{
    margin:0;
    margin-top: 0;
    margin-bottom: 0;
    padding: 30px;
    background-color: darkblue;
    text-align: center;
    font-size: 24px;
    color:white;
  }
#navside{
    float: left;
    width:20%;
}
article {
    float: left;
    padding: 20px;
    width: 80%;
    height: auto;
    background-color: snow;
   /* height: auto; /* only for demonstration, should be removed */
  }
  footer{
    padding: 10px;
    background-color: darkblue;
    color:silver
  }

  section::after {
    content: "";
    display: table;
    clear: both;
  }
footer{
  text-align: center;
}
 
  h3{
    color:darkblue;
  }
#tbl{
  width: 100%;
  color: white;

}
 #tbl > thead{
  background-color: slategray;
}
 #tbl > td{
  border:1px solid rebeccapurple; 
}
#tbl1 tr, td{border: 1px solid darkblue;}