A young man wears a mask on the right side of his head as he stands on a bridge with the European Central Bank at left in Frankfurt, Germany, Thursday, October 29, 2020. (Photo by Michael Probst/AP Photo)

Vehicles move past a man wearing a protective mask against COVID-19 as he waits for the bus in Karachi, Pakistan on December 11, 2020. (Photo by Akhtar Soomro/Reuters)

A conscript hugs a girl as he says goodbye to family members at a local railway station during departure for the garrisons, in Sevastopol, Crimea on November 9, 2022. (Photo by Alexey Pavlishak/Reuters)

US President Joe Biden departs the White House for California, where he will review damage from recent flooding, in Washington, DC, USA, 19 January 2023. (Photo by Jim Lo Scalzo/EPA/EFE)

A male elephant named Mahadevan is tied in a truck as he is being transported for an annual temple festival in Kochi, India, March 10, 2020. (Photo by Sivaram V/Reuters)

President Joe Biden holds a baby as he visits a COVID-19 vaccination clinic at the Church of the Holy Communion Tuesday, June 21, 2022, in Washington. (Photo by Evan Vucci/AP Photo)

A man is silhouetted in front of the Allianz-Arena as he walks his dogs at sunrise in Munich, southern Germany, Friday, April 10, 2015. (Photo by Peter Kneffel/AP Photo/DPA)

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.