Santa, a dog abandoned two days before Christmas, is looked after by Charlene Gunner at Battersea Dogs and Cats Home on December 27, 2012 in London, England. The home was founded 150 years ago and has rescued, reunited and rehomed over three million dogs and cats. The average stay for a dog is just 28 days although some stay much longer. Around 550 dogs and 200 cats are provided refuge by Battersea at any given time. (Photo by Peter Macdiarmid)

First lady Michelle Obama (R), joined by daughters Sasha Obama (C) and Malia Obama, is presented with the official White House Christmas Tree on November 25, 2011 in Washington, DC. The tree, a 19-foot-tall balsam fir, was grown on Schroeder's Forevergreens farm near Neshkoro, Wisconsin. (Photo by Brendan Hoffman/Getty Images)

U.S. Army Sgt. Patricia Foust receives a free Christmas tree on December 7, 2011 at Fort Carson in Colorado Springs, Colorado. More than 600 soldiers and military families at the base chose trees as part of the annual Trees for Troops program. (Photo by John Moore/Getty Images)

Meri Nirmala Sari, 11, poses in her traditional costume before a performance August 6, 2002 in Ubud, Bali, Indonesia. Meri dances with the Gunung Sari Peliatan dance group and has become a professional. She started dancing at age 5. (Photo by Paula Bronstein/Getty Images)

Vice President of Lebanese Wildlife Alexandra Youssef, checks a fox at a vet clinic in Beit Mery, Lebanon on March 26, 2021. (Photo by Mohamed Azakir/Reuters)

A hen, a dog and a rabbit playing cards, circa 1956. (Photo by Evans/Three Lions)

People applaud as a delivery robot departs from the Nihonbashi Post Office to deliver traditional New Year's Day cards, during a ceremony in Tokyo on January 1, 2023. (Photo by JIJI Press/AFP Photo)

Bryan Berg was introduced to card-stacking by his grandfather at the age of 8. He is a self-taught artist in all of the techniques he uses today. Berg's freestanding card structures are based on a grid-like arrangement, which Berg tested in a structural engineering lab to support 660 lbs per square foot―using no tape, no glue, no folding, and no tricks.