Little bit of HTML/CSS code

I have used WYSIWYG website creator software to make a navigation bar with buttons in the style I want. The code is in the file index.html. However, my software does not allow me to modify their default drop-down menu templates. So I need someone to write the HTML/CSS code for a template for a drop-down menu which will appear when I hover/mouseover a navigation bar button. Sample appearance is shown in the file index.jpg. Note that the colours in the drop-down menu are not correct. They should be the same as the "Engines" navigation bar button -- 000 135 081 dark green for background and 255 214 016 yellow for text, with these colours reversed for hover/mouseover. The layout of my navigation bar may change in future, so your code must include instructions how I can alter the position, size, text, colours and links of the drop-down menu tabs. Also, where to add it into my [login to view URL] file. If you use WYSIWYG web creator software to do this job, tell me what program you are using so I can buy it! It's got to be better than what I am using. I don't need a whole website design, or even one website page. Just a bit of code. This should be a very simple job for the right person. So cheap bids only please.