Angular Material - Global color variables

Question

Looking at the Angular Material documentation, they recommend using a -theme file per component to manage applying any theme-related styles to a specific class.

Answer 1

I have defined primary,accent and warn colors as css custom variables in the styles.css file like so:

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

$my-primary: mat-palette($mat-blue-grey);
$my-accent: mat-palette($mat-amber, A200, A100, A400);
$my-warn: mat-palette($mat-deep-orange);

$my-2-primary: mat-palette($mat-pink, 400, 200, 600);
$my-2-accent: mat-palette($mat-blue, A200, A100, A400);
$my-2-warn: mat-palette($mat-deep-orange, 500, 300, 700);

.dark-theme {
  $my-theme-dark: mat-dark-theme($my-primary, $my-accent, $my-warn);
  @include angular-material-theme($my-theme-dark);
  $primary: mat-color($my-primary);
  $accent: mat-color($my-accent);
  $warn: mat-color($my-warn);
  $fg_palette:map-get($my-theme-dark, foreground);
  $bg_palette:map-get($my-theme-dark, background);
  $fg:map-get($fg_palette, text);
  $bg:map-get($bg_palette, background);

  --primary: #{$primary};
  --accent: #{$accent};
  --warn: #{$warn};
  --fg: #{$fg};
  --bg: #{$bg};
}

.dark-theme-2 {
  $my-2-theme-dark: mat-dark-theme($my-2-primary, $my-2-accent, $my-2-warn);
  @include angular-material-theme($my-2-theme-dark);
  $primary: mat-color($my-2-primary);
  $accent: mat-color($my-2-accent);
  $warn: mat-color($my-2-warn);
  $fg_palette:map-get($my-2-theme-dark, foreground);
  $bg_palette:map-get($my-2-theme-dark, background);
  $fg:map-get($fg_palette, text);
  $bg:map-get($bg_palette, background);

  --primary: #{$primary};
  --accent: #{$accent};
  --warn: #{$warn};
  --fg: #{$fg};
  --bg: #{$bg};
}

And used these variables in any of my components like so:( in my-custom-component.scss)

.some-class {
    color: var(--primary)
}

.another-class {
    background-color: var(--bg)
}

.yet-another-class {
    border-color: var(--accent)
}

By doing like this, i can change any value related to color in any component, because these variables are global (defined in styles.css) As i change theme, these colors also change according to new theme's color