NEW YORK — Behind every big fashion success there’s a singular creative vision. That’s why Gwen Stefani made sure to be part of every aspect of her new contemporary line, L.A.M.B., which debuted this week. “I drew every stitch, every seam,” Stefani says. “I did all the fittings. This is my baby.” Form-fitting T-shirts, pants with a swath of fabric over the bum and plenty of hardware give L.A.M.B. a look of casual glamour with a touch of punk. For more on her new label, see story Gwen Had a Little L.A.M.B.