.foo {
  background-image: url("1.png"),
    url("2.png"),
    linear-gradient(
      to bottom,
      #000   0%,
      #fff 100%
    )
  ;
}

@font-face {
  font-family: "f";
  src: url("f.eot#a") format("embedded-opentype"),
       url("f.woff") format("woff"),
       url("f.ttf") format("truetype"),
       url("f.svg#b") format("svg");
}