Doubts in documents needed for h1B

Hi Folks, greetings…
My employer confirmed that my application is selected in the lottery and asked me to share the list of documents like my degree cert, mark sheet, passport, resume, experience letter from previous employers, etc… they have also asked for details of gaps in employement. I have a 3 months gap in-between, so how do i explain that? is the gap much significant? i didnt want any issues as this is my 3rd attempt and i got selected… please help…