Shrinking violets, beware: The current vogue for purple-hued footwear is certain to make all who participate the center of attention. With an ambassador like Catherine Zeta-Jones, what can one expect? The Welsh actress, no wallflower she, opted to pair a gold minidress with a set of lilac peep-toes for a recent “Late Show with David Letterman” appearance — the better to pop on the small screen. And, it seems, a slew of starlets, singers and girls-about-town have followed suit (or, perhaps more precisely, stiletto). Stella McCartney and Aerin Lauder paired lavender heels with neutral dresses while Rihanna and Zoe Kravitz added oomph to basic black sheaths with mulberry pumps. Meanwhile, Katie Holmes ditched her usually monochromatic uniform for a strapless ruby gown, topped off with a pair of amethyst platforms. Prince would be proud.