Material Angular cheatsheet: mat-icon-button with background-color on hover

mat-icon-button_overlay-on-hover.css

/*
  <button mat-icon-button>
    <mat-icon aria-label="Close main menu">close</mat-icon>
  </button>
*/

/*
  By default the opacity for the overlay focus is set to 0,
  but it could be nice for the user to have a feedback when his mouse is hover the button.
*/
.mat-icon-button:hover .mat-button-focus-overlay {
  opacity: 1 !important;
}