Need to display different icon as per light or dark theme

Hello Team,
We’ve a requirement to display different icon as per theme selection in Grafana. For example, a.png file needs to be displayed for light theme and b.png file needs to be displayed for dark theme. Currently I’m building grafana from source and as per my investigation I see icons are kept inside public\img\icons_light_theme and public\img\icons_dark_theme and these files are read from _icons.scss file (located at public/sass/base/) in following way.

.gicon-dashboard {
background-image: url(’…/img/icons_#{$theme-name}_theme/icon_dashboard.svg’);
}

I tried to create similar entry for our icon file and tried to load , but still I’m not getting that icon displayed in the application.
.gicon-customlogo {
background-image: url(’…/img/icons_#{$theme-name}_theme/custom_logo.png’);
}

Testing Theme

Could you please guide me how to load different icon as per theme selection?
Thanking you in advance for your help.