with regard to this info:
you can find it here:
you can use this code:
<style type="text/css">
@media all{
.my-header-grid.ui-grid-b .ui-block-a { width: 30%; }
.my-header-grid.ui-grid-b .ui-block-b { width: 40%; }
.my-header-grid.ui-grid-b .ui-block-c { width: 30%; }
}
}
</style>
<div class="my-header-grid ui-grid-b" data-theme="a">
<div class="ui-block-a ui-bar-a" data-theme="a">
<div align="left" style="padding-left:5px;padding-top:3px;height:33px;height:40px;">
<a href="#" class="ui-btn-left" rel="external" data-mini="true" data-role="button" data-icon="back" data-theme="a">Back</a>
<a href="#" class="ui-btn-right" data-role="button" data-icon="gear" data-iconpos="notext">Edit</a>
</div>
</div>
<div class="ui-block-b ui-bar-a">
<div align="center" style="padding-top:3px;height:33px;text-align:center;height:40px;">
<div style="padding-top:7px;">
<article role="heading" aria-level="1">expand </article>
</div>
</div>
</div>
<div class="ui-block-c ui-bar-a">
<div align="right" style="padding-top:3px;height:33px;height:40px;">
<a href="#" class="ui-btn-left" data-role="button" data-icon="plus" data-iconpos="notext">Add</a>
<a href="#" class="ui-btn-right" rel="external" data-mini="true" data-role="button" data-icon="refresh" data-theme="a">Refresh</a>
</div>
</div>
</div><!-- /grid-b -->
if by any chance your programming with c# mvc razor engine don't forget to write the css media tag with 2 @ like so @@media because the razor engine treats 2 @ as one.
you see and can play with all of the designs shown here in this link: