Wayfair announced this morning a new $36.3 million in funding, but it’s not for the company’s flagship site, Wayfair.com. No, the round will be dedicated to the expansion of Joss & Main, a members-only home decor flash sale site offering collections curated by celebrities that has experienced significant growth since its founding in 2010.

The funding comes from Battery Ventures, Great Hill Partners, HarbourVest Partners and Spark Capital. All four firms were involved in Wayfair’s massive $165 million round in 2011. Shortly after raising that last round, the e-commerce giant consolidated the majority of its sites, with Joss & Main one of the few exceptions.

“Joss & Main has gained tremendous traction over a very short period of time through its unique approach to curated e-commerce,” said Niraj Shah, CEO and co-founder of Wayfair.com, in a release. “The site hit its highest sales day on Cyber Monday by a factor of over 50 percent and sales are up 10-fold since last year. It’s clear that shoppers love the Joss & Main experience and with the help of our investors we expect to grow membership and sales at an even greater pace.”

The company claims that Joss & Main has reached 3 million members and has reached an annualized run rate of $100 million in revenue.

As you might expect of any e-commerce site boasting such growth, mobile is an increasingly significant part of Joss & Main’s business, according to the company’s executives. The division released a mobile app earlier this year, and mobile shopping accounts for a third of the site’s sales.

The intersection between mobile, social, and shopping is increasingly a hot space and so Wayfair and Joss & Main’s success in mobile will no doubt be challenged by startups and incumbents alike. Though the release says nothing about what, specifically, the funding will be used for, I’d expect continued emphasis on mobile innovation to be a top priority.