Find Parent

HTML

<div class="yo" style="width:100%">
    <div class="no" style="width: 50%">
         <a href="#" id="make-red">Make 100 red</a>
    </div>
</div>
<div class="yo">
    Should Not Change
</div>

CSS

.red{background: yellow}

JavaScript

$(function() {
    $('#make-red').click(function() {
        $(this).parent().parent('.yo').addClass('red');
    });
});



jQuery.fn.findParent = function (selector) {
    var curParent = this.parent();
    var curParentWithSelector = this.parent(selector);
    var curO = curParent;
    while (curParentWithSelector.length === 0) {
        curParent = curO.parent();
        curParentWithSelector = curO.parent(selector);
        if (curParent.is('body')) return this.parent(selector);
        if (curParentWithSelector.length === 1) return curParentWithSelector;
    }
}