1 : Ok, so h5 should be from my style.css
2 : I checked before, and my header is correct :
<head>
<title>...</title>
<link rel="stylesheet" href="<?php bloginfo('stylesheet_url'); ?>" type="text/css" media="screen"/>
... (other meta and header stuff) ...
<?php wp_head(); ?>
</head>
3 : Ok, will try
4 : ok, will try this also
thx