try using position absolute, top and left on the icon. You may or may not need to throw in a z-index as well. As for the embedded style in the <i …> element, i would personally include that style in the css sheet for better readability.
Also, be sure that you are using the correct selectors. Please see:
Now concerning the third question, I will leave you with this instead. When stuck on a problem regarding styling, this is what helps me. I go through the style sheet, take a look at each rule, and ask myself these questions:
Do I need this?
Why do I need this? / What purpose does it serve?
Does it affect the parent/child element? How so?
It also helps to do an * { outline: 1px red solid} for troubleshooting. These are just some general tips that may prove to be useful.