There’s a lot to be said for the rumpled look, especially when embraced by cool girls with a sweet side, the kind who have been Marc by Marc Jacobs’ core constituency from the get-go. Come spring, they’ll be in undone heaven, as Jacobs sent out a host of do-it-your-way pieces all with that wrinkled, crinkled, just-out-of-bed ease. On the frothy side, there were prairie and garden-print dresses, ruffled baby dolls, creamy knits and an adorable frilled onesie. Jacobs countered the softness with bold spliced stripes and boyish fare, like baggy engineer striped pants and nubby college-professor tweeds, shown as they might be worn by one of the Little Rascals. Either way, electric neon accessories added a hint of New Wave Eighties. Think playful, through and through.