How can I add custom style ?

[gimx]

Hello,

I want use GS for my next website. I have made the HTML/CSS template. It's very simple and the "basic" editor is enough. But I want use one class of my css and add it in the dropdown menu in the editor.

I just need add a span around the text whith this style :

Code:

<span class="my-class-in-css-file">Text</span>

I have read ckeditor wiki but I don't understand...

Can you explain me in "detail" please ?

Thanks