It was a lazy Sunday afternoon, the lull before the storm of Monday morning madness of alarm clocks, traffic jams and deadlines. The clock struck three and Rebecca’s elbow still rested on the arm of the tapestry-covered sofa. With her fingertips she began caressing the rough piping that ran along its seams. Simultaneously, the toes of her left foot moved back and forth across the edges of the sheepskin rug. (Source: https://www.flo-joe.co.uk/cae/students/tests/read3pr1.htm)
I understand the word-by-word translation of the sentence but it makes no sense to me. I think it somehow related to the sofa which was previously mentioned but I don't understand in which way.