How can I make this? Highlighting the skills on a CV. (articulate 360)

Hi there, 

I have a job advert and a CV in which learners must locate the skills needed for the job. 

This needs to be an invisible hotspot, which only changes colour(state) when clicked.  Every time they click in the right place, I want the skill to be highlighted and a point to appear at the top of the screen. 

I'm very new to Storyline and I'm struggling to get my head around what triggers I will need and the order in which I should process the tasks. 

Any guidance would be greatly appreciated. 

Many thanks

Andy