There's also this SASS mixin: http://www.adrenalinmedia.com.au/the-agency/insights/this-changes-everything-css-fluid-properties.aspx http://www.adrenalinmedia.c

There's also this SASS mixin: http://www.adrenalinmedia.com.au/the-agency/insights/this-changes-everything-css-fluid-properties.aspx http://www.adrenalinmedia.com.au/the-agency/insights/this-ch... The linear equation solver is there, but it assumes px, and there's no license...