I'd like to put a picture rail up in our ground floor hallway and paint the area above the same colour as the ceiling in order to show off the cornice to best effect. I'm unsure whether to end the picture rail at the bottom of the stairs or to continue it up the stairwell. At some point it will simply have to finish in "mid air" if you follow my drift and there will need to be a vertical line between the ceiling colour and and wall colour below the picture rail. I really need a diagram to explain this more clearly but hopefully the problem will be understandable/recognisable. Grateful for advice/experience of what works.