How to show a X mark in checkbox when ng-disabled value true in angularjs

I need to show a X mark in red color for checkboxes, if ng-disabled condition satisfies true. How to achieve this? I'm new to angular js anyone help me. This is I have tried so far:

if (module.Name === 'val1' || module.Name === 'val2') {
            return true; // Here I'm validate ng-disables true or false
        }