Bug on Multi Step for Contact Form 7

Hello, I use contact form 7 and the Multi Step for Contact Form 7 Pro plugin and I would like to ensure that once a choice of the form is selected that there is a visual change that we know what we have chosen before going to the next step. apparently it does not work. Here is an image of the desired rendering once clicked thank you for your support

I need change the look of the button once it clicked
Like that for example

View post on imgur.com

For the moment when I select an option on the form the button stay the same .. that why I put “radio button” on the bottom of each button of the form to show what is selected

https://pac.ma-maison-econome.fr/landing/

waiting for your reply