angular 5 matsnackbar change action button color : <p>I'm using MatSnackBar for my angular 5 project, and I cannot seem to change the color of the 'action' button. </p>

<p>I've injected the snack bar to my HttpInterceptor:</p>

<pre><code>    this.snackBar.open('Invalid Login', 'Ok', {
                    duration: 2000,
                    panelClass: ['my-snack-bar']
                });
</code></pre>

<p>my css:</p>

<pre><code>    .my-snack-bar {
        background-color: #E8EAF6;
        color: #3D5AFE;
    }
</code></pre>

<p>How can I change the 'Ok' action button color?</p>
