change Style

src/app/components/shared/comment-list/comment-list.component.html

 <mat-toolbar [ngStyle]="{'background-color':'#bbdefb'}">List of Questions</mat-toolbar>
-<mat-card class="card-container" [ngStyle]="{'background-color':'#4db6ac'}">
-  <mat-card *ngFor="let comment of comments">
+<mat-card class="outer-card" [ngStyle]="{'background-color':'#b2ebf2'}">
+  <mat-card class="card-container"  *ngFor="let comment of comments">
     <mat-card-title>{{comment.subject}}</mat-card-title>
-
     <mat-divider></mat-divider>
     <mat-card-content>
       <p>{{comment.body}}</p>

src/app/components/shared/comment-list/comment-list.component.scss

@@ -5,3 +5,21 @@ mat-card {
 mat-card-content>:first-child {
   margin-top: 20px;
 }
+
+mat-toolbar{
+  border-radius: 10px;
+  margin-bottom: 20px;
+}
+
+.card-container{
+  background-color: #4dd0e1;
+  opacity: 0.7;
+  border-radius: 2px;
+}
+
+.outer-card{
+  border-radius: 8px;
+}
+
+
+