E-filed returns generally sit in Pending status for 24-48 hours before coming back as either Accepted or Rejected. Sometimes state returns stay in Pending for several days or even longer. Please see What does pending mean? for more detailed information.
You are not answering my question. Your plat form says within 24/48 hours. I have not been accepted or rejected by the IRS.
Please reference the above suggestions by @MoniqueLO_ and the Help Article here. It states your return can be pending for several days. Also, the IRS is experiencing a backlog from processing last year's returns as well which it also acknowledges. Once you click Transmit Return Now, you are now on the IRS timeline.