The bounding box is approx 1000x600, and some images are 500x100, while some others are 400x100 (extreme examples). Now I\'d like to scale both up to the maximum size the bo
You can't do it like that. You can edit the image element's width and height attributes...
You can set the width and height to either pixels or percent. Note that you don't have to write px when using pixels, but you do have to write % when doing percentage. So you can do something like...
... but that will take 100% of the width and height of the parent element. So be sure you know what the parent element is and its dimensions.