A LESS Mixin to convert hex color values to rgba color values to be used in conjunction with the vertical gradient mixin from Bootstrap.

Hex to rgba Less mixin (for use with the Bootstrap Vertical Gradient mixin)

.hex-to-rgba-vertical-gradient ( @start-color, @start-alpha: 1, @end-color, @end-alpha ) {
	// Start Color
	@start-red: red(@start-color);
	@start-green: green(@start-color);
	@start-blue: blue(@start-color);
	@start-rgba: rgba(@start-red, @start-green, @start-blue, @start-alpha);

	// End Color
	@end-red: red(@end-color);
	@end-green: green(@end-color);
	@end-blue: blue(@end-color);
	@end-rgba: rgba(@end-red, @end-green, @end-blue, @end-alpha);
}

// How to use
// Using Bootstrap's gradient mixin
.alpha {
	.hex-to-rgba-vertical-gradient ( @gray-middle, .5, @gray, .5 );
	#gradient > .vertical(@start-rgba, @end-rgba);
}

// output
// .alpha {
// 	background-image: -webkit-linear-gradient(top, rgba(196, 196, 191, 0.5) 0%, rgba(155, 155, 152, 0.5) 100%);
// 	background-image: linear-gradient(to bottom, rgba(196, 196, 191, 0.5) 0%, rgba(155, 155, 152, 0.5) 100%);
// 	background-repeat: repeat-x;
// 	filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#80c4c4bf', endColorstr='#809b9b98', GradientType=0);
// }