Can not add white space with 'innerHTML' between buttons
All white space in HTML, including line breaks, gets reduced to just one space. That's the rule.
Don't use spaces. They are not exact. Use an element and give it a width, padding, or margin in CSS.
If you MUST use spaces, use
. This is a non-breaking space, and all of them get printed. But really, don't use it.
You have to use (non-breaking space) for each space to prevent browser from displaying it as one space.