How can I make checkboxes have a design of a growing graph when selected

I am designing a form and I have at some questions only 4 answers and I want to have them have a design that looks like a growing graph.

[design I am trying to achieve][1] [1]: https://ift.tt/ED2KBru

Right now i have the label of the checkboxes inside them and some padding and border, I can create them to be with no border radius and full background and changing when checked, but I am curios if there is a code I can find online or someting for the growing box on top because I have and idea of how to create a diagonal gradient but I do not know how to create a cursive design.