Hi, I am using Dreamweaver 4, so that might be the problem; let me know if it is. I cannot afford to upgrade.
After I finished your first CSS lesson, the first time I have tried CSS, I opened it up in Dreamweaver, and it didn't look correct. The Main Heading and Main Navagation headings are overlapping. When I open it in the browser, it looks alright. I tried your mypracticehtms.htm file, and that had the same result in Dreamweaver.
What do you think?