Can i style my ion-radio items

Hi all

I’m making an application using ionic, sass.
So i made an ion-radio list with items that comes from the back-end.
But now I want every item to have another background color. So i used sass to loop over these items. But it is not working. The thing is when I print my items in a < ul >, it is working.

Is it not possible to style the ion-radio tag?

my sass code :

$seagreen:#5fc3ad;
$yellow:#d99a25;
$blue:#26a8dc;
$red:#c24342;
$green:#36af6b;
$purple:#557cba;
$darkPurple:#242945;
$black:#000000;

$colors: $seagreen, $yellow, $blue, $red, $green, $purple, $darkPurple,$black;

@for $i from 1 through length($colors) {
  ul:nth-child(#{length($colors)}n+#{$i}) {
    background: lighten(nth($colors, $i), 10%);
  }
}

Thanks in advance