I changed it, but I put it in ../local/custom.css :
.demo-home .section-lead {
background-image: url(../images/landing.jpg);}
.demo-home .section-lead:before {
background: radial-gradient(0% 20% at 20% 20%, #111126 0%, #6c6c77 25%);
opacity: 0.1;
}
I just added this to ../css/custom.css and it worked. I was told to use ../local for any customization. Now I'm confused.