Coloured cardstock is the backdrop everything else rests on. You use it for bases, intermediate layers, the matting around your photos and all those small details that give a layout room to breathe.
We stock it in A4 and in packs of 50 sheets of the same colour, which is what pays off when you find a shade that works with a collection and you know you'll get through it. There are yellows, blues, greens, oranges and more.
A tip: always pick your cardstock colour from a secondary tone in the patterned paper, never the dominant one. The result is far more harmonious.