How long does it take to become proficient in CSS?
Assuming that you know HTML you can learn the basics in about a 2 to 3 days, become proficient in about 2 to 3 weeks, and become really good (know by heart all the cross-browser perks, and how to avoid them) in I’d say 2 to 3 years.
Of course if you don’t know HTML, I’d start with that first. Get to know HTML and then CSS. Mixing the two together might get you confused.
This is just my opinion, others might feel differently 
I have learned the basics of HTML. I have some understanding on CSS but table-less design is kicking my butt right now.
They way I would recommend learning CSS:
- Understand the Box model
- Understand the float and [url=http://www.w3schools.com/css/pr_class_clear.asp]clear CSS properties.
- Understand the position, and [url=http://www.w3schools.com/Css/pr_pos_z-index.asp]z-index CSS properties, and specifically position:relative and position:absolute.
- Go on with “basic stuff” like fonts, colors, images, etc.
HTML and CSS… I started in May of 2007… and still learning.
i dunno, i ain’t proficient yet 
i’ve been writing css since netscape 4 and ie 4, so about twelve years
Depends on the person. Their are far too many variables to give you an x answer. Like saying, “How long does it take you to learn Russian?”
It’s not just learning the code, it’s learning how to use it in a plethora of different situations, how various code elements interact with one another, etc. etc.
When you start learning make sure you have some good HTML and CSS tools for validating your scripts.
I find the majority of browser conflicts are due to errors and warnings in your script. Each browser has its own way of deciding what to do if your code is not 100% W3C Code Compliant.
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