Following Zeno’s advice I tried Taco today and I found it extremely useful. It allows to work with styles and integrates perfectly with CSSEdit. Worth to try:
Taco HTML Edit is free software for Mac OS X. It is designed to simplify the process of creating attractive web sites that render correctly in various browsers. Taco HTML Edit includes tag wizards, which generate HTML markup for you. Taco HTML Edit also helps find errors in your HTML markup, and it can even check spelling in your documents. For those people who use PHP scripts in their development, Taco HTML Edit includes tools for PHP management.