Appearance > Theme Options > Custom CSS not working in all browsers

I tried placing the following code in both the custom css and a child theme and in both scenarios it worked on Firefox 37..0.1 but not Safari 5.1.1 on a Mac. Any thoughts? #branding #access, #colophon #access-footer, #branding ul.menu ul a { background: linear-gradient(#3D3D3D, #000000) repeat scroll 0 0 transparent; } The site is catholicproductions.com/cpblog