How can I make the top of this overlay transparent?

.blog-post .black-overlay {
   display: block!important;
   position: absolute;
   right: 0;
   bottom: 0;
   left: 0;
   height: 32px;
   width: 100%;
   background: linear-gradient(to bottom, rgba(0,0,0,0) 0%, #000 250%);
}