Tip calculator app solution using JS

to be honest these is a best exercise to practice java basics Math methods like ParseInt(),.Fixed(),parseFloat() but for the most of it it helps me to test my ability with events specially 'keyup' events. i added some overshot JavaScript sauces ....enjoy it to build these web app i use js and css for the most part of the process and also in the html I added data-id and data-value to mark my elments in unique ways for the JavaScript. The main logic is to calculate the tip amount per person and total expenditure per person for a random group of people and I don't think anyone could have encounter math's issues in these challenges but the main task in these project is to think scenarios(cases) and to prepare reaction for that in the JavaScript as a programmer , these small web app require to think different scenarios(cases) case-1]when a user didn't click(add values) on the bill input and also when a user didn't click on the rate btn case-2]when a user insert a 0 value to person input[cant be 0 warning] case-3]when a user insert in custom input and changes idea to click the rate btn and vice versa case-4]when a user insert a 0 value to the bill input and also a reset btn have a set back to default functionality which will restore everything