[10 marks] Below is the HIML and CSS for an online form to perform a login. These files are complete and cannot be changed. The error text (span with class ="error") is not visible when the form initially loads. When the form fields have valid data, you should hide the errors; otherwise they should be shown. Fach of the three form fields should trigger the event handler. Part A. Write the event handler registration code using the "blur" event. Part B. Write a single JavaScript event handler function that can handle the validation of all three fields. Manipulate the CSS to perform these tasks, do not add or remove DOM or CSS elements The regular expression to detect a text string is /[aZAZ]+$/ The regular expression to detect a date is /d{4}\d{2}d{2}$ The method for testing if a string matches pattern is .test(String object)