But the text remains opaque.
In CC's responsive site builders a background image can be made translucent by changing the opacity. A problem that arises by doing so is, that any element placed upon that background, will inherit the opacity, and text will more or less disappear into the background and be hard to read. Therefore I have placed another container on top of the first one, given it a transparent background, and and then popped the text on top of the new container. That solves the problem, and it works as far back as in IE9.
This technique is not dependent on any particular programme, it can be done in all the responsive site builders that CC has created.
The file is supposed to be a 'how-to', it's not actually meant to be made into a component, but if you want to do so, just select the whole lot (the 'wrapper' container) and edit out this content bit.