Code A Simple Software - Wire-frames provided! -- 2

Hello, I need a software developer to code a program for me with beautiful GUI. This software does a very simple job, It uses a default html templates and substitutes the values entered by the user in software with the default texts in the template.. For example, the h1 header says... "this is the header" and software should have a column to enter header text and whatever user enters there..it should be added in place of default text which is "this is header". also utilizing default CSS but if user enters a html tag in the input box such as tag or any different font color than it should overwrite the default CSS. The whole program does this exact job.. all the time.. substitution in the placeholder. Software does requires a basic text editor making it easy for users to add html codes..bold italic heading underline font color bg color etc.. I'll explain things on Skype if you have any doubt or stuck somewhere. At last program creates a new html file out of default one for users to upload on their server. Attached are the wireframes... I'll provide the html template! You are free to choose any platform you are good at and convenient for you. If you can code the program in java and could provider installer for both mac and windows that would be awesome! :)