Question

In a responsive design, how can the width of a <figcaption> be made to adjust according to the width of the <img>, but not exceed it?

 <section>    
    <figure>
        <img src="link.jpg">
        <figcaption>Caption</figcaption>
    </figure>
</section>

The corresponding CSS only limits the <img> and not the <figcaption>, see:

How can the <figcaption> be constrained along with the <img>, without using max-width: 200px (or 12.5em) on the <figure> container?

---

Here are the important bits of CSS (full on JSFiddle):

section figure {
    position: relative;
    margin: 0 auto; /* to center it */
}

section figure img {
    max-width: 100%;
    vertical-align: middle; /* to make sure images behave like blocks */
}

section figure figcaption {
    position: absolute;
    right: 0; bottom: 0; left: 0;
}

Answer 1

Setting max-width: 100%; display: inline-block; (http://jsfiddle.net/vZpmq/1/) or float: [left|right] (http://jsfiddle.net/cdmU3/1/) on the section would cause it to shrink-to-fit it’s content (and the box it’s in). You might need to rework some other things to fit those changes, though.

Alternatively, try setting width: 100%; height: auto; on the img, and set the width on the figure element? http://jsfiddle.net/9yUsP/

(setting height: auto; on the img means it’s retain it’s aspect ratio regardless of height or width attributes set on the img element itself)