I wrote this fairly straightforward cross-browser linear gradient mixin:
@mixin gradient($from-color, $to-color) {
background-color: mix($from-color, $to-color); /* Fallback */
background-image: -webkit-gradient(linear, 0% 0%, 0% 100%, from($from-color), to($to-color));
background-image: -webkit-linear-gradient(top, $from-color, $to-color);
background-image: -moz-linear-gradient(top, $from-color, $to-color);
background-image: -ms-linear-gradient(top, $from-color, $to-color);
background-image: -o-linear-gradient(top, $from-color, $to-color);