style.css

            .header{
                background-color: rgb(51, 163, 0);
                color: white;
                padding: 8px;
                top: 0px;
                position:fixed;
                font-family: "arial", sans-serif;
                overflow: auto;
                width: 99%;
                z-index: 900;
            }
            
            .header,.left{
                left: 0px;
                text-align: left;
            }
            .header,.right{
                float: right;
            }
            
            /* unvisited link */
            .header, a:link {
                color: white;
                text-decoration: none;
            }

            /* visited link */
            .header, a:visited {
                color: lightcyan;
            }

            /* mouse over link */
            .header, a:hover {
                color: white;
                text-decoration: underline;
            }

            /* selected link */
            .header, a:active {
                color: white;
                text-decoration: none;
            }