All the details on the HGTV star's Ines Di Santo gown — plus, see an exclusive sketch

Christina El Moussa may have shocked everyone with her Newport Beach, California, wedding to boyfriend Ant Anstead on Saturday, but when it came time to find her dress, there were no surprises — the bride knew exactly what she was looking for.

“I knew I wanted it to be romantic,” El Moussa, 35, tells PEOPLE exclusively.

She turned to the design team at bridal atelier Ines Di Santo to create her dream dress, a form-fitting mermaid-style, lace design featuring a low-back with buttons, mermaid silhouette and detachable sleeves.

“We added sleeves to a dress that didn’t have sleeves, and we made them detachable so that I could walk down the aisle with this dress with long sleeves and lace and then take them off for the party,” she says, adding that design made her “feel beautiful.”

She paired the dress with a long, flowy veil and center-parted beach waves.

“It’s classic and really beautiful,” El Moussa added. “Ant will be surprised, but he’s going to love it.”

Credit: Ines di Santo

The Flip or Flop star, 35, married Wheelers Dealers host 39, in a surprise “winter wonderland” wedding at their home, as first revealed exclusively by PEOPLE.

To successfully pull off their surprise “I dos,” the pair invited 70 of their closest friends and family members to meet at their house, where a charter bus then transported the group to watch the Newport Beach Christmas Boat Parade.

Credit: Rich Lander | CHARD Photo

But instead, guests walked into the couple’s wedding. El Moussa and Anstead — who began dating in October 2017 — exchanged vows with their children close by.

“We wanted to make it about the kids,” says Anstead. “It’s the six of us. We’re a blended family so it was really important for them to be a part of it.” El Moussa shares daughter Taylor, 8, and son Brayden, 3, with ex-husband Tarek, and Anstead has daughter Amelie, 15, and son Archie, 12, from a previous marriage.

“We wanted it to be rustic romance,” El Moussa says of the vibe of their intimate wedding.

The bride told PEOPLE that she’s officially changing her last name to her new husband’s. “It has a nice ring to it, doesn’t it?” she says. “Christina Anstead. We couldn’t be any happier!”

The HGTV star and the TV presenter made their relationship public in January, marking the moment with a photo of the couple taking a bike ride. They had clearly been keeping their romance under the radar for a month or two, as Christina later said they met “at the end of 2017,” and Ant revealed they celebrated a 6-month anniversary on April 30.