gistfile1.sass

    @if not $supports-gradients or $compile-all {
        .#{$prefix}nlg {
            @if $grid-header-background-gradient != null {
                .#{$prefix}grid-header-ct,
                .#{$prefix}column-header {
                    background: repeat-x 0 top;
                    background-image: theme-background-image($theme-name, 'grid/column-header-bg.gif');
                }
            }

            @if $grid-header-over-background-gradient != null {
                .#{$prefix}column-header-over,
                .#{$prefix}column-header-sort-ASC,
                .#{$prefix}column-header-sort-DESC {
                    background: #ebf3fd repeat-x 0 top;
                    background-image: theme-background-image($theme-name, 'grid/column-header-over-bg.gif');
                }
            }
        }
    }