JSFiddle - React, Tailwind, and code Playground

HTML

<body ng-app="App" ng-controller="MainCtrl" class="{{colorScheme}}">
    <button type="button" ng-click="toggleScheme('hg')">HG Theme</button>
    <button type="button" ng-click="toggleScheme('hg-disabled')">HG Theme Disable</button>
    
    {{colorScheme}}
</body>

CSS

.hg {
    background: #EEE;
}

JavaScript

var app = angular.module('App', []);

app.controller('MainCtrl', function ($scope) {
    
    // Default scheme set to hg
    $scope.colorScheme = 'hg';    
    
    // Scheme switcher fn
    $scope.toggleScheme = function (sheme) {
        switch (sheme) {
            case 'hg': $scope.colorScheme = 'hg';
                break;
            case 'hg-disabled': $scope.colorScheme = 'Normal';
                break;
        }
    };
});