A Pen by Gideon Kreitzer.

mixin.styl

// ######################################### MIXIN ##########################################

linear_gradient(origin, colors...)
    
    fallback = colors[1][0]

    colors = join(', ', colors)
    colors = unquote(colors)

    background-color: fallback
    background-image: -webkit-linear-gradient(origin, colors) // Chrome, Safari
    background-image:    -moz-linear-gradient(origin, colors) // Firefox (3.6 - 15)
    background-image:     -ms-linear-gradient(origin, colors) // IE 10
    background-image:      -o-linear-gradient(origin, colors) // Opera (11.1 - 12.0) 
    background-image:         linear-gradient(origin, colors) // W3C

// #################################### IMPLEMENTATION ######################################

:root
    linear_gradient(right, red, orange, yellow, green, blue, indigo, violet)

// or

body
    linear_gradient(top, rgba(0,0,0,0.0), rgba(0,0,0,0.3))

Stylus-Mixin-for-Linear-Gradients.markdown

Stylus Mixin for Linear Gradients

A Stylus mixin for linear gradients with support for comma-separated splat arguments. In part created as a work-around / abstraction for this.

The method for retrieving the fall-back background colour can do with some improvement, such as averaging the colours or selecting a colour by means of passing an additional argument.

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