Do CSS files get sent to brower for the browser to render the page, or are CSS files processed server side, with only the HTML page being sent to browser?
They are sent to browsers, along with JS files and other resources referenced in your HTML page. Of course, browser may never actually request these files (for example, if you disabled images display), but nothing gets applied server-side.
CSS files are sent to the browser as well (unless they are already cached client side)
yes, css file sent to browser to reder page.
this image will help you to understandm, where css file get downloaded to client browser
you can use firefox + firebug plugin to check this
CSS is processed client-side by the browser. So yes, it is downloaded by the browser along with HTML, images, Javascript etc.
Everything is sent to the browser what is supposed to design your page including CSS, HTML, Javascript.
Css behaves like html files, they get fetched by the browser and then the browser does all the rendering. The same thing happens with image files and javascript. That is why you have different behaviors for different browsers, each browser interprets the css files as they want and that's why you have to tune up your css files for IE, Firefox, chrome, opera, etc...
The best way to make your css files work in almost all the browsers (apart from IE6) is writing the css file using the w3c standards, Firefox, Chrome, opera and IE9 are supposed to be W3cCompliant.
Regards.