Question: I am starting up a brand new web project and would like to know if I can safely use multiple CSS classes nowadays.

`<div class="float-left bold bordered"></div>`

Do most common browsers support this, or will a significant percentage of my visitors run into major trouble viewing the page?

I'm not worried about special cases like Netscape 1.0 users, but browsers and versions usually used in companies these days.

Answer: 
Nearly any modern browser should support this, it is apparently buggy in IE <= 6, but you should be fine as this lack of functionality would hinder many major sites / applications.

The following link has a chart showing support for multiple CSS classes by browser:

[CSS Support By Browser](http://www.quirksmode.org/css/contents.html)

Netscape 1.0 will probably not support this, as Netscape lacked support for it in 4.0. [Source](http://www.blooberry.com/indexdot/css/syntax/selectors/spechtml.htm)

> 
> Netscape 4.0+
> 
> 
> * Multiple class names for an element are not supported.
> 
> 
>
Yes, every major browser supports this.