Ionic 4 In ion-select i want hide default icon add my png down icon

I am trying hide default icon below code but cant work please let me know.how to hide this.

.select-icon {
.select-icon-inner {
display: none !important;
}
}

Hi!
the easier way to hide the default icon is to do this.

ion-select {
color: transparent;
}

Color transparent not works. It will hide everything. Because It make color transparent for selected value also.