Brandys said: Here the Html <div class="tabs">
<div class="tab">
<input type="radio" id="attr_tab-1" name="tab-group-1" checked>
<label class="tabs-label" for="attr_tab-1">Caractéristiques</label>
<div class="content">
<div role="tabpanel" class="tab-panel tabstats active" id="tabstats">
<!-- Things tab 1 -->
</div>
</div>
</div>
<div class="tab">
<input type="radio" id="attr_tab-2" name="tab-group-1">
<label class="tabs-label" for="attr_tab-2">Compétences</label>
<div class="content heightTabskills">
<!-- Things tab 2 -->
</div>
</div>
</div> Ok, Here's your problem. You are trying to use IDs in your html to then reference in your css. As noted by myself and Jakob above, IDs are not valid for character sheet html/css. See the wiki I linked to above for full details on this. Furthermore, the name of your html elements must be prepended with "attr_", not the ID of the elment (which is invalid anyways). So for an example of all of this: <input type="radio" id="attr_tab-1" name="tab-group-1" checked> Should be <input type="radio" class="tab-1" name="attr_tab-group-1" checked="checked"> Now this does mean that your current use of labels will not work as you can't use the for="..." syntax to link the labels to their radio buttons. See the CSS Wizardry wiki for details on how to handle tabbed sheets in Roll20 character sheets. I'm sure that more experienced sheet authors like Brian and Jakob will see other things that need fixing here as well.