HTML and CSS Reference
Because of the reduced readability, it is preferable to work with the uncompressed
style sheet and have the minification step repeated whenever the CSS file is updated.
Minification can be done automatically (for example, by using the Bundle tool mentioned
earlier) or manually with an online tool such as Clean CSS. 7
One optimization that minification tools cannot do is to find and remove unused
CSS rules. A useful Firefox plug-in that can help you perform this task is Dust-Me
Selectors. 8 This plug-in can test pages individually and also scan through an entire site in
search of unused selectors.
Even with your code normalized and validated, there can still be some differences in the
way a web page is rendered in various browsers, especially in older versions. It is therefore
necessary to test your site in all the browser versions you want your site to support.
To make this testing process easier, you can use BrowserStack, 9 which is an online
tool for checking browser compatibility. It shows you how your site will look on different
versions of the browsers you select. You can also see how your site will look on mobile
devices and tablets.