Boutons Augmenter/Diminuer la Taille du Texte ?

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window.resizeBy(0,-10);
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<!--La feuille utilisé par défaut-->

<link rel="stylesheet" type="text/css" href="normal.css" title="normal">

<!--Une feuille alternative-->

<link rel="alternate stylesheet" type="text/css" href="grand.css" title="grand">

<script language="JavaScript" src="changement_css.js" type="text/javascript"></script>

<ul>

<li><a href="#" onclick="setActiveStyleSheet('normal'); return false;">Normal</a></li>

<li><a href="#" onclick="setActiveStyleSheet('grand'); return false;">Grand</a></li>

</ul>