// vertical
@mixin gradient-vertical($start: #555, $end: #333) {
	background-color: $start;
	background-image: linear-gradient(to bottom, $start 0%, $end 100%);
}

// vertical to opacity
@mixin gradient-vertical-to-opacity($color, $opacity: 0) {
	$rgba: rgba(red($color), green($color), blue($color), $opacity);
	background: linear-gradient(to bottom, $color 0%, $rgba 100%);
}

// horizontal
@mixin gradient-horizontal($start: #555, $end: #333) {
    background-color: $start;
    background: linear-gradient(to right, $start 0%, $end 100%);
}

// horizontal to opacity
@mixin gradient-horizontal-to-opacity($color: #555, $opacity: 0) {
    $rgba: rgba(red($color), green($color), blue($color), $opacity);
    background: linear-gradient(to right, $color 0%, $rgba 100%);
}

// radial
@mixin gradient-radial($inner: #555, $outer: #333) {
	background-image: radial-gradient(circle, $inner, $outer);
}