give gray offlien scale to website

1window.addEventListener('online', function(e) {
2    // add your logic to update the UI when online
3    console.log("You are online");
4    document.body.style.filter = 'grayscale(0)';
5}, false);
6
7window.addEventListener('offline', function(e) {
8    // add your logic to update the UI when offline
9    console.log("You are offline");
10    document.body.style.filter = 'grayscale(1)';
11}, false);
12