Angular – Remove mat-expansion-panel border & box-shadow

add mat-elevation-z0 class. Works like a charm, I needed to use that recently.

<mat-accordion>
 <mat-expansion-panel class="mat-elevation-z0" (opened)="panelOpenState = true"
                   (closed)="panelOpenState = false">

   <mat-expansion-panel-header>

     <mat-panel-title>
       <span class="right">Filter</span>
     </mat-panel-title>

   </mat-expansion-panel-header>

   <p><app-data></app-data></p>

 </mat-expansion-panel>
</mat-accordion>