[SOLVED] Bug when inserting elements overlaying header image

I use Atahualpa 3.7.1.

I tried to insert something (a text in the exemple) overlaying the header image. In the section header image/Overlay Header Image
I put a html code for instance :

<p style="text-align: right;"><span style="color: #ffffff;"><strong>Espace Clients</strong></span></p>

It mess up my header area with a white space upon and above the image : to avoid it, I added few <br/>, the white space disappeared but there is still the white space above the image.

Could you please explain me how to do it?
Thanks in advance.

Isabelle