Comment faire pour modifier la Sémantique de l'INTERFACE utilisateur de l'image de fond

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<h3 class="ui header">Different types of Dental Fillings</h3>
<p>You are maybe know that there are only one type of dental filling and that is mostly termed as <b>'Pasta'</b>. But did you know that there are various types of dental fillings? Check it out now!</p>
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<p>Yes I know you probably heard about braces because they're quite the trend now these days. But did you know that there are different of braces that depends on the case of the patient.</p>
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<h4 class="ui inverted header">Dr. Pamela B. Rivera</h4>
<p>Specialized in Airway and Dental Sleep Medicine | Craniofacial Pain | TMJ Dysnfunctional Management</p>
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Donc je suis de nouveau à la Sémantique de l'INTERFACE utilisateur et je suis en train d'expérimenter la page d'Accueil et je veux changer l'image de fond de l'un noir qui est sur le dessus.
Pas la barre de navigation mais le tout noir tout comme toute chose dans la Sémantique de l'INTERFACE utilisateur du site web. J'espère que vous pourrez m'aider!

OriginalL'auteur Christian. | 2015-10-09