1. Not really sure why your doing this, IMHO this tool is really not useful/necessary anymore. It used to be important prior to the existence of vendor prefixes, mobile devices(responsive), caniuse.com, build tools, linting. Since then its not as reliable or powerful and does not account for a lot of things, not to mention has loads of false positives.
2. You can not point to a website to get a valid wsc that is not how you use the tool. It is meant to be used in production. You instead need to copy paste each css file separately. You will still receive errors in a few of the files, but those are on purpose and allowed which is why this tool is utterly useless.
case in point:
Facebook: http://jigsaw.w3.org/css-validator/vali ... g=&lang=en
Twitter: http://jigsaw.w3.org/css-validator/vali ... g=&lang=en
Github: http://jigsaw.w3.org/css-validator/vali ... g=&lang=en
These are probably three of the best coded front-ends there is...
3. prosilver was created in 2007! so get in your wayback machine and check it then! Not to mention it was built to support IE6
. The coding used was very poor and problematic to say the least. There are several coding practices that were used that literally every front-end dev cringe just looking at them. I mean wtf
#cp-menu .panel #topicreview span.corners-bottom-bottom span
. Through the years we have worked tirelessly to fix/tweak/patch/hack at it to attempt to fix/maintain it, but the fact is that its a lost cause. Add to that the complexity of attempting to make it seem responsive(seem is the proper term cause that is not what it is!)...
The WSC is by far the least of the concerns.
Lets take a look at specificity for example
3.0.0: http://cssstats.com/stats?link=https%3A ... F3.0.0.css
3.0.14: http://cssstats.com/stats?link=https%3A ... %2F3.0.css
3.1.11: http://cssstats.com/stats?link=https%3A ... %2F3.1.css
3.2.1: http://cssstats.com/stats?link=https%3A ... %2F3.2.css
3.3 (WIP): http://cssstats.com/stats?link=https%3A ... %2F3.3.css
pay attention to the numbers on the left side as you will note we started with a specificity of 222
and are now looking at 55 in 3.3 when theoretically we should be around a 30 max. Its not an easy task And this is only the css, that is not to mention maintaining the html!!!!!!
4. The entire website is based on prosilver which means you are starting with a shit base and building off of that which means you are not only going to inherit shit but exponentially perpetuate it.
5. We are currently working to fix all the issues but it takes time and work. Not to mention man power! Ultimately the fix for it is a completely new front-end system/theme
There will be more info on this coming soon