How do I add CSS to a TextInput

Hello.

Can someone please explain to me how i add CSS to a textinput. I tried reading the guide, but couldn't make it work.

What i did was adding a style.css to my project, and in that one i have a ID called .inputbox

.inputbox {
	border-radius: 24px; 
	-moz-border-radius: 24px; 
	-webkit-border-radius: 24px; 
	border: 3px solid #2E9623;
}

You used the class selector .inputBox instead of the ID selector #inputBox.