WordPress › Support » Can't Center Images

I've been working on a new theme but can't work out how to center images.

If you look on this post:

The image should be centered. I clicked the center button on the WordPress media browser and added this CSS:

img.aligncenter {
    display: block;
    margin-left: auto;
    margin-right: auto }

But I can't see why it's not in the center. I've had success with adding:

<div style="text-align:center">image</div>

But that's only a quick fix and I can't do that every time.

Any ideas?

Thanks everyone!

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