How do i change the styles of the labels in the form

I have created a form to create articles but the form has labels which not bold but rather insignificant. I would like to make the labels look larger and in different color like red, and not black.I would like to know which css files i should be editing to change the styles of the form. I know how to change the template css of item and category view but it only changes the front end side of the article.

Hello,
create a CSS rule for CSS class
flexi_label

Regards

Where should i create the .flexi_label{font:bold}
I mean in which file should i make these changes???
The item or category template css files????

You can put it in any CSS file that gets loaded,

e.g. in one of your joomla template CSS files

also there is a backend parameter to add CSS to the item form

and better use !important
e.g.

.flexi_label { font:bold!important; }

components/com_flexicontent/templates/default/css/item.css

I made the following changes to this css file but with no visible changes

.flexi_label { font:bold!important;
font-size:200%!important; }

Please tell me if have to change else where

sorry but for all css question we need a live site to provide the best help !
regards