Generated by SassMeister.com.

SassMeister-input-HTML.html

<div>
  Done with the config
</div>

SassMeister-input.scss

// ----
// Sass (v3.4.12)
// Compass (v1.0.3)
// ----

$slideout_list_width: 35%;

$slideout_config: (expanded: 104% - $slideout_list_width, available: 100% - expanded, max: percentage(available / expanded));

div {
  background: #ccffcc;
  max-width: map-get($slideout_config, max);
}

SassMeister-output.css

$number: "available/expanded" is not a unitless number for `percentage'

SassMeister-rendered.html

<div>
  Done with the config
</div>