Project: Beating LED Heart

I just started working with 555 timers and decade counters (4017), and I wanted to make a fun first project. So, I decided to make a little heart out of LEDs with 2 layers: 1) the outline of the heart 2) the inside of the heart. Inside the circuit there is a 2-step sequencer that alternates the light between the two layers (the "beating"). The speed of the beating is variable. Here are a few pics a and short video: