Rendre personalisable le fond pour internaute

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    <img src="img/bg1_thumb.png" alt="Fond 1">
    <a href="#" onclick="choose('style1.css');">Choisir</a>
</div>

<div class="bg_group">
    <img src="img/bg2_thumb.png" alt="Fond 2">
    <a href="#" onclick="choose('style2.css');">Choisir</a>
</div>

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