James van Riemsdyk, Zack MacEwen, and Max Willman scored, and Carter Hart made 45 saves for the Flyers (21-33-11), who were coming off a 5-2 win at the St. Louis Blues on Thursday that ended a 13-game skid on the road.
"Against a team like that, with that kind of skill, you always have to play smart," Philadelphia coach Mike Yeo said. "I always believe the best way to stop speed is before it starts, and I didn't think we did a very good job of that."
Kadri scored on a wrist shot from between the circles to give Colorado a 1-0 lead at 7:20 of the first period.
Van Riemsdyk tied it 1-1 at 13:02 when he scored on his own rebound.
"We definitely worked hard," van Riemsdyk said. "It's just a matter of executing the little details against a team like that on the end of a back to back [because] you're not going to have much room for error. Certainly, those little details become critical."
Makar made it 2-1 with a power-play goal 44 seconds later when his point shot through traffic beat Hart at 13:46.
"On an individual basis, I don't think I had my best game, but at the end of the day that's why we have depth," Makar said. "Effort-wise, I thought that it was there all game. I thought we had really good back pressure from our forwards, which helped us on the back end create good gaps, and it kind of all starts from there for us."