Hey Dave,
You can easily add inline styles to most of the shortcodes with the style attribute. This will add inline CSS to alter the shortcodes. For example, if you wanted to alter the width of an image, you could do something like this:
[image style="width: 100px;"]
Personally, I’d recommend using max-width due to the fact that X is responsive. This will put a cap on your image width, but will also let it size down if it gets too small on a mobile. Doing that would look something like this:
[image style="max-width: 100px;"]
Don’t hesitate to let us know if you need anything else!