Radio buttons label's into Alert aren't properly stylized

I’m using a ion-select into an Alert component, it works perfectly programmaticaly, but the style isn’t totally nice so I try to change the style by this way :

> <ion-select style="color:#fafafa; font-color:#fafafa" [(ngModel)]="idDate" (ionChange)="change_selectDateCotisa_date()" style="height:50px">
>   <ion-option style="color:#fafafa; font-color:#fafafa" *ngFor="let o of optionsDateCotisaDate" [value] = "o" [checked]="false">
>   {{o}}
>  </ion-option>
> </ion-select>

#app.variables.scss

$colors: (
primary: #387ef5,
lightPrimary: #74b2fb,
secondary: #32db64,
danger: #f53d3d,
light: #f4f4f4,
dark: #222,
favorite: #dede6a,
$alert-md-message-text-color: #fafafa;
$alert-md-radio-label-text-color: #fafafa;
$alert-md-radio-label-text-color-checked: #fafafa;
$alert-md-background-color: color($colors, dark);
$alert-md-button-text-color: color($colors, lightPrimary);

For result the style doesn’t work totally yet : the radio button labels are black however they must be white/#fafafa according to $alert-md-radio-label-text-color. Moreover I observed all other selectors and didn’t find it : see SASS variables topic of https://ionicframework.com/docs/v2/api/components/alert/AlertController/
Please note that Alert’s checked labels instances are properly white/#fafafa colored, background color is properly dark.

Cordova CLI: 6.3.1
Ionic Framework Version: 2.0.0-beta.11
Ionic CLI Version: 2.0.0-beta.37
Ionic App Lib Version: 2.0.0-beta.20
OS: Windows 8.1
Node Version: v4.5.0