Favor CSS over images


Use CSS3 rule-sets instead of images as a style sheet file is much smaller, especially when compressed.
In addition, calling a style sheet only generates one HTTP request, whereas each image generates an HTTP request.

Rounded corners for boxes should be generated in CSS3 rather than by images.

Use the following:
#cadre {
border-radius: 10px;
<dvi id="cadre">
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