By Cam Vigliotta It’s easy to forget the importance of comfortable bedding when we place so much emphasis on other sleep habits. When experts tell us to put away our phones, seal out light and limit caffeine before bed, they fail to recognize the significance of supportive linens. But this is where Gravity Blankets comes in. The brand makes some of our favorite sleep essentials, including weighted blankets, duvet covers and bedsheets. And right now, you can pick up a bunch of Gravity’s offerings for 20% off through March 31. We’ve recently fallen in love with the Z Weighted Blanket for its dua…