How to write specification

Hi, I've been programing for some time, but I never tried to write code for two different application in same way. How when I work with more programmers it's even worse. Everyone is forcing it's way of writing functions inside classes or writing variables, etc. My idea is to code according to the standard protocol so that in future it would be easier to make applications. Is there some specification (or standard) how to write code for web application, but which describes all possibilities(writing css, JS, php, etc.)? Thanks in advance, Dusan -- made by ndusan