Develop a JS script to analyze and extract keyword from webpage

We are looking for a long term, part time programmer. This will be a paid screening task, based on the results we will decide whether to continue and hire you on a part time basis. Short Description - We are looking to create a Client Side JavaScript code that will do the following. The script will extract all the texts (based on rules) from the page and send them to our server, the server will send back a list of queries (keywords / phrases) that we would like to turn into a Hyper Link and mark with a double underline (with some rules as well). The code should be as light weight and fast as possible, and must support most browsers specifically (Chrome, FireFox and Explorer) *Please notice that the server side is already fully coded and ready to use. For writing purposes we use Mark = turn into a hyperlink with double underline Query = either a single word (Keyword) or a number of words together (Phrase) Keyword - example - Director, Sales, Java Phrases - example - Director of sales, Java Developer, Experienced Nurse Long Description – --- Important notes --- 1. The code must not use the innerHTML function 2. The code must support multiple languages including but not limited to : English, French, German, Japanese, Chinese. 3. The code should be as light weight and fast as possible, the user should not feel as if the browser is stuck or waiting. 4. The code must support most browsers, specifically these must be supported: Chrome, FireFox and Explorer. --- Sending the Text to the Server --- 5. When sending the text to the server, send it in an efficient way, with minimal text, for example you should not send texts that are located within tags (As described in bullet #6) --- Getting results from the server --- 6. The server will send back a list, in JSON format, with the queries that it has found within the text you sent over. Please notice that the queries will be arranged in order of importance. --- Marking the queries within the page --- 7. Queries should be marked with a double underline and turned into a hyper link, please use the same font as the surrounding words within the paragraph. 8. You should never Mark Queries (keywords / phrases) that are located in the following tags: A, INPUT, TEXTAREA, SELECT, OPTION. 9. Each query should not be marked more than 2 times within the entire text, and not more than 1 time within each paragraph. 10. When Marking Queries (keywords / Phrases), the first query within any paragraph should always be marked, starting with the second query we want to make sure the page will not be over crowded, so within every paragraph from query 2 and onward check only mark it if the total amount of Marked words is smaller than or equal to X% of the total words within the Paragraph (x is an input). 10.1. Example – A paragraph has 50 words, and we have 2 queries out of the list that the server sent back to you that are found within this paragraph, the first query from the list (notice that the list is ordered by importance) should be marked no matter how big it is, as for the second query we do the following, assuming that the first query has 3 words and the second has 3 words as well, if X = 0.05 = 5% then we will not mark it, if X = 0.06 = 6% or higher then you should mark it. * Please see a visual example within the attached file.