Question: I have installed Robot Framework. I am searching for example Test Cases for Robot Framework using Selenium Library.

I need a guideline to start writing TCs on Robot Framework. Help is appreciated.

Answer: 
Probably because of Quirksmode?

Add a Doctype!
Why adding the style to the `input`? It isn't doing anything.
The `input` has a `type="checkbox"` attribute. Thus `text-align:center;` is a bit strange because there will never be text inside. Even the `vertical-align` property does not belong there. There isn't anything inside the checkbox to align...

The CSS code you have will do in order to align everything in the span in the middle.
Check [this jsFiddle](http://jsfiddle.net/UghzT/1/). I deleted the ´style` attribute and it still works great.