These are some tips I have assembled to help you with moving past the basics of CSS and on into the world of mastery. Designing your own web site in CSS should be fun and rewarding. :}
http://www.csszengarden.com +++For a look at high-level CSS work
http://www.w3.org/TR/CSS2/ +++Official W3C CSS 2.1 standards
http://www.w3.org/TR/2001/WD-css3-roadmap-20010523/ +++ Official W3c CSS3 hub
http://www.css3.info/ :: http://www.w3schools.com/css3/css3_intro.asp :: http://www.css3.com/ :: +++CSS3 blogs
Tips for Mastering CSS (Cascading Style Sheets)
1. Pick simple selectors
2. Learn a new selectors
3. Make effective use of classes and id’s
4. Use external style sheet as opposed to internal styles or in-line CSS
5. Constantly practice newer CSS 3 techniques
6. Practice arranging and nesting your (X) HTML documents properly
7. Plan your site layouts ahead of time using sketches and wireframe diagrams
8. Learn the rules of specificity
9. Study the layouts of sites that you enjoy visiting
10. Keep your CSS style sheets and layouts in a folder for future use and updating
11. Never be afraid to try something new
http://blog.freewebdesigntutorials.info
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