Thank You.
In the “SWITCH STYLE” tab, at the bottom, you will find the “Alternative Dark Mode Switch” setting. There you can add your custom buttons class or ID name (e.g. #my_custom_btn). And finally save the settings. In frontend now your custom button will act like a Dark Mode toggle button.
Alternatively, you can add the “darkmysite_switch_trigger()” onclick function in your button to make it work like dark mode button. e.g.
<button onclick="darkmysite_switch_trigger()">Toggle Dark Mode</button>