Move over, Elle Woods! Reese Witherspoon turned heads in a swimsuit showing off her stunning figure while enjoying a luxurious vacation in Italy this week, RadarOnline.com can reveal. The Little Fires Everywhere star, 48, sizzled in a plunging black one-piece with buttons dotting the neckline as she took a boat ride to Portofino and San Fruttoso with friends on Thursday. The actress flaunted her natural beauty with a makeup-free face and knotted her blonde hair in a bun while posing for photos with her pals. In the pics shared by Daily Mail, Reese slipped into an oversized white button-up dres…