Thanks for the quick reply Zach!
I understand the transition will never be smooth, but I'm mostly just looking for a solution that ensures the front card is always above the other two. This original version I had worked on functioned correctly, but ultimately having more than just the 3 cards visible doesn't fit the design (https://codepen.io/ryjohnson/pen/2b3fee8715f4d7c968f2395ff6d66159). You can see as you drag, the next card eventually jumps in front of the previous frontmost card.