dnet-applications/frontends/dnet-is-application/src/app/app.component.css

.sidenav-container {
    height: 100%;
  }
  
 .sidenav {
    width: 350px;
 }
  
 .sidenav .mat-toolbar {
    background: inherit;
 }
  
 .mat-toolbar.mat-primary {
    position: sticky;
    top: 0;
    z-index: 1;
 }