index.js
function(selector, properties, value) {
    let rule = postcss.rule({selector: selector})

    let decls = _.map(properties, function(property) {
        return postcss.decl({prop: property, value: value})
    })

    rule.append(decls)

    return rule
}
function(selector, properties, value) {
    let rule = postcss.rule({selector: selector})

    let decls = _.map(properties, function(property) {
        return postcss.decl({prop: property, value: value})
    })

    rule.append(decls)

    return rule
}
Make a functional CSS rule
@param  {string} selector   The selector to use including a dot or hash (. or #)
@param  {array} properties The property names to assign to the declaration
@param  {string} value      The value for each declaration
@return {array}            an array of PostCSS Rules