CSS: Is a hidden object clickable?

With display: none it is still part of the DOM. It just isn’t rendered in the viewport.

As for clicks on elements with visibility: hidden, the events are not fired.

jsFiddle.

$('div').click(function() {
    alert('Hello')
});

div {
    width: 100%;
    height: 100%;
    visibility: hidden; 
}

<div>abc</div>