Fixes hover color

Author: vbakke

src/app/component/circular-heatmap/circular-heatmap.component.css

@@ -8,8 +8,8 @@
   shape-rendering: crispEdges;
 }
 
-.normal-button {
-  background-color: white;
+.title-button {
+  background-color: transparent;
   border: none;
   text-align: left;
   cursor: pointer;

src/app/component/circular-heatmap/circular-heatmap.component.html

@@ -247,7 +247,7 @@ <h2>Nothing to show</h2>
                 <mat-expansion-panel-header>
                   <mat-panel-title>
                     <button
-                      class="normal-button"
+                      class="title-button"
                       (click)="
                         $event.preventDefault();
                         navigate(