Board Thread:Support Requests - Getting Technical/@comment-4151266-20151104041249/@comment-1757994-20151106094737

 td[style *= "width: 100%;"] * { width: inherit; height: auto; }
 * in Common.css

 then  .banner-wrapper { width: 100%; }
 * (optional) in Template : Notice
 * in Common.css (instead of the suggestion above)

.banner-wrapper * { width: inherit; height: auto; } (MediaWiki translates align= and width= to the correct CSS, but you really don't need text-align here.)

For the user page, you'd then do 

If you don't like "banner-wrapper" for the class name, feel free to choose a different one.

For the background, it's possible to have JavaScript detect the window size and pick an appropriately-sized background image, but a better way is just use CSS to set the background properties and scale the image.

For example, in Monobook.css,  body { background-image: url(http://images.wikia.com/world-war-2/images/5/51/Wiki-background.png); background-size: cover; } which works for Monobook. The background of the Oasis skin is provided by the skin based on File:Wiki-background (no .png). It can be overridden in Wikia.css.  body.background-dynamic.skin-oasis::after, body.background-dynamic.skin-oasis::before { background-image: none; }

.background-image-gradient { display: none; }

body.background-dynamic.skin-oasis { background-image: url(http://images.wikia.com/world-war-2/images/5/50/Wiki-background); background-size: cover; } Wikia may or may not get bent out of shape if you screw with how Oasis delivers the background. Also, Wikia changes Oasis regularly, so it may be easier not to define Wiki-background and just use Wiki-background.png the way Monobook does.