Whenever I am using the .click function, it is highlighting the text and other elements that have the same class name. Does anyone know what is causing this and / or how it can be fixed?

Example -

 

[ Button 1 ]

[ Button 2 ]

[ Button 3 ]

If buttons 1, 2, and 3 all had the same class name "button", whenever I click on a button the other two become highlighted.