JS - can't change color but can change display property

Not sure why this isn't working. This is the rendered HTML:

<h2 id="step-3-question">...and for how much?</h2>

So just in the console, I'm running:

$('#step-3-question')[0].style.display = "none"

Which works fine, so the element is being found, BUT these do not have any effect:

$('#step-3-question')[0].style.color = "white"
$('#step-3-question')[0].style.color = "#000000"

Any thoughts on why?