Customized Online Calculator

Custom Online Calculator The purpose of this project is to code a custom pricing calculator. The Calculator has already been designed & built in HTML/CSS, but needs functionality added to it. Also looking for clean well commented code, so that values can easily be changed in future. Please read carefully the requirements below and follow the link which will aide you in understanding: [login to view URL] BRIEF OVERVIEW ------------------------------------------- The only section on this page that needs attention is the 'Total Costs' section, this is where the calculator resides. All other elements on the page are functioning and do not need work done. REQUIREMENTS ------------------------------------------- Total Costs Section - As the user fills out the input field from the 'Need more than fifteen licenses?' section, 'Total Costs' section should automatically update without the need for a Submit button and without refreshing the page. The user should also be able to go back and change the value in the number of additional licenses input field. - Where it says 'Monthly Plan' this text should change depending on which option they selected on a previous page ... in the URL of that link I provided, you will see PROGTYPE=1, this signals to the page that the 'Monthly Plan' was selected on the previous page ... PROGTYPE=2 signals the 'Yearly Plan' was selected. - To the right of the 'Monthly Plan' text it says '$299' this value should update depending on which plan was selected. - Where it says '0 Additional Licenses' 0 should change with the value entered in the input box above ... So if a user enters the number 20, that part in 'Total Costs' would read '20 Additional Licenses'. By default it should read '0 Additional Licenses' until the user enters in a number. - To the right of the '0 Additional Licenses' text it says '$0' this value should update depending on the number entered in the input box above, and the cost per license. PLEASE SEE THE LICENSE CALCULATION INFO BELOW. By default it should have the value of $0 ... because initially when this page is loaded no number will be in the Step 2 input box above. If a user enters more than 85 additional licenses in the input box above, this value will display the text 'Call for pricing'. - where it says '($0 each)' this is a pricing bracket, this value should reflect what price bracket the additional licenses are being charged at. PLEASE SEE THE LICENSE CALCULATION INFO BELOW. If a user enters more than 85 additional licenses in the input box above this value will display the text '($? each)'. - At the bottom where it says 'Total Cost $0' that value should add the 2 above values for the total. Again this should be updating as the user fills in the form and makes changes. If a user enters more than 85 additional licenses in the input box above this value will display the text 'Call for pricing'. - At the bottom where it says 'License Total 0' that value should take the value entered in the input box above and add 15 to the number ... as 15 licenses are always included with each plan. So if 20 was entered into the input box above, that license total will read '35'. Additional License Calculations & Price Brackets (the pricing per license depends on the quantity and also whether they choose a Monthly or Yearly plan) Monthly Plan - Additional License Cost 1-15 Licenses ($20 per license) 16-35 Licenses ($18 per license) 36-85 Licenses ($16 per license) > 85 Licenses (Call for Pricing) Yearly Plan - Additional License Cost 1-15 Licenses ($17 per license) 16-35 Licenses ($14 per license) 36-85 Licenses ($11 per license) > 85 Licenses (Call for Pricing)