Here is a yoga video I just did a few minutes ago and I am in absolute LOVE with it! I really hope you try it! It says it's for morning, which definitely works, but I just did it at night too and it obviously works just as well.
I am new to Yoga, and it was the first time I've ever tried it... But I noticed a HUGE improvement just after doing this 7 minute video in my flexibility. I started out with only being able to bend over to my mid-calf, and by the end I was touching the ground. I definitely look forward to doing this over and over to see my improvement! :)