[add some details to css]

static/css/sidenavRepository.css

 /* the sidebar menu */
 .sidenav {
+    width: 130px;
     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 */
+    background: #eee;
     padding-top: 20px;
 }