three.js/editor/js/Menubar.View.js

Menubar.View = function ( editor ) {
	var menuConfig,
		optionsPanel;

	function onLightThemeOptionClick () {

		editor.setTheme( 'css/light.css' );
		editor.config.setKey( 'theme', 'css/light.css' );

	}

	function onDarkThemeOptionClick () {

		editor.setTheme( 'css/dark.css' );
		editor.config.setKey( 'theme', 'css/dark.css' );

	}
	

	// configure menu contents

	with(UI.MenubarHelper) {

		menuConfig = [
			createOption( 'Light theme', onLightThemeOptionClick ),
			createOption( 'Dark theme', onDarkThemeOptionClick )
		];

	}

	optionsPanel = UI.MenubarHelper.createOptionsPanel( menuConfig );

	return UI.MenubarHelper.createMenuContainer( 'Help', optionsPanel );

}