Test checked state of checkbox from materializecss with cypress

I have the following html generated by materializecss:

<label>
    <input type="checkbox" id="new-spec-load-pet-checkbox" checked="">
    <span>Load Pet Example</span>
</label>

Now I want to test if the checkbox is checked or not, however, when I click on it, the checkbox itself changes, so it's working, but, the html does not. I assumer materializecss somehow overlays the checkbox with images.

How would I test that the checkbox has a certain state if it's not layed out in the html?