How to set color of toggle buttons

Question

I have group of toggle buttons. They are very light and disappear in the background on poor monitors with a high brightness level.

How can I properly style

Answer 1

Add the following styles in styles.scss

@import '~@angular/material/theming';
@include mat-core();

$primary: mat-palette($mat-indigo);
$accent: mat-palette($mat-yellow, A200, A100, A400);

$theme: mat-light-theme($primary, $accent);

@include angular-material-theme($theme);

html,
body {
  height: 100%;
}
body {
  margin: 0;
  font-family: Roboto, 'Helvetica Neue', sans-serif;
  .mat-button-toggle-checked {
    background-color: mat-color($primary);
    color: mat-color($primary, default-contrast);
  }
}

ps: I assumed you have selected scss and custom theme