Help! How do you carpet a bi-level/split entryway with a stair runner?

My husband and I bought a home that we’ve been working on for about a year. We refinished the wood floors after tearing up the (gross) carpeting. To fill you in, our front door opens into a split entry… two choices: up or down. Our upstairs and downstairs are decorated in two completely different themes.

After looking for nearly a year, I finally found the perfect carpet for my living room. The runner will go down my steps from the top of the stairs (living room) but how does that work at the bottom of the stairs? Do I end it where the door is? Or at the bottom of the stairs? Do we get a different runner for the stairs leading to the downstairs?

Any help is appreciated!

Since its two completely different levels and you really wouldnt see the carpet runner til you start going upstairs or downstairs, it would define the two different spaces. If it was one set of stairs, i’d say use the same runner, but its two, so, you can use two.