Grenzo,

Ideally you want to tag the image with a css class (e.g. <img class="imageborder" />) and then use that selector to define the border color in a CSS file like the following:

img.imageborder{
border:1px solid #CC0000;
}

which will attach a red border around the all images with that class.

Regards,

Rick.

Grenzo,

You can add the CSS to the Stylesheet Editor located on the Admin > Site Setting page, right at the bottom. This updates the portal.css file.

Rick.