Question about hiding/displaying the text on Dashboard

Hi there, 

Hope you have a good day. 

Today, I would like to ask about how to hide/display text on dashboard. 

I've created an attached dashboard and would like to set up when selecting/placing cursor on each goal, the text dissapears, whereas none of goals selected, the text should be desplayed to hide (goal/discription). 

So far, the containers and action setting have been scratched by my side, the set-up is not successfully completed. The language is in Japanese but hope the contents are all familiar across the globe!! 

Thank you so much for your kind assistance and help! 

Warm regards, 

Koki