That is correct. Someone needs to ask her: "Did you ever send or receive emails specifically marked "Confidential", "Secret", or "Top Secret?". As you've stated, there are no secure documents marked "Classified" (except maybe in the movies or on TV.) This is Hillary's version of "it depends on what the meaning of the word "is" is."
I’m sure she’d have a weasel-worded answer for it no matter how you phrased it. I don’t know why any reporter has to ask her since we now know beyond any shadow of a doubt that she sent and received thousands of classified documents, including dozens of SAP documents and her email telling a subordinate to remove a classified header and send the doc unsecured has been made public. Those are facts not speculations.