Hello,
I often find myself needing to adjust column widths for the various responsive screen sizes I'm developing for. A quick-and-dirty example using Bootstrap classes might be as follows:

<section class="row">
    <article class="col-xs-12 col-sm-6 col-lg-8">
        Content goes here
    </article>
    <figure class="col-xs-12 col-sm-6 col-lg-4">
        <img src="image.png" class="img-responsive">
    </figure>
</section>

With Tailor I can only set the column widths once, and can't change them depending on the screen size. Am I missing something?