That's ok.

Say like you wanted to copy something, you would click and drag and the it would highlight the text.
I wrote the spoiler text (the bit that gives the answer) in the same colour as the background so someone who might not want the answer doesn't have to see it. So the only way you can see the text is to highlight the background and it will show up.
I hope that makes sense, if not let me know and I'll try again
