[create css file for the sidebar]

static/css/sidenavRepository.css

+/* the sidebar menu */
+.sidenav {
+    position: fixed; /* stay in place on scroll */
+    z-index: 1; /* stau on top*/
+    top : 0; /* stay on top*/
+    left: 0; /* on left side of screen */
+    padding-top: 20px;
+}
+
+
+/* Sidenav filters */
+.sidenav a {
+   padding: 6px 8px 6px 16px;
+  text-decoration: none;
+  font-size: 25px;
+  color: #818181;
+  display: block;
+}
+
+/* when you hover over filters, change colors */
+.sidenav a:hover{
+    color: #f1f1f1;
+}
+
+/*change style of sidebar on smaller screens */
+@media screen and (max-height:450px){
+    .sidenav {padding-top: 15px;}
+    .sidenav a {font-size: 18px;}
+}