In a text overlay of the nine-second video, Shi wrote, "When you actually go to a game and realize the yellow line is only on TV..." We realized this the hard way too, and we're not kidding when we say it changes everything.

The rest of the clip — which is set to a snippet of No Doubt's "Just a Girl" — sees an obviously confused Shi looking around the crowd and trying her best to focus on the field. Despite the confusion, we hope she still had a good time because the atmosphere surrounding a football game is unbelievable.

OK, now that you know the yellow line is only for TV, some might be wondering, "How is a first down determined in person?" Well, the chain crew manages three signal poles on the sidelines:

• The "rear rod" — marks the beginning of the current set of downs.
• The "forward rod" — marks the line to gain, or the first down line.
• The "box" — marks the line of scrimmage.

The two rods are attached by a chain exactly 10 yards long, and the offense aims to move those 10 yards down the field to gain a first down and advance toward the opponent's end zone.