saturation($color) Returns the saturation component of a color. See

if($condition, $if-true, $if-false) Returns one of two values, depending on whether or not $condition is true

unquote($string) Removes quotes from a string. If the string is already unquoted, this will return it unmodified.

desaturate($color, $amount) Makes a color less saturated. Takes a color and a number between 0% and 100%, and returns a color

selector_append($selectors...) Return a new selector with all selectors in $selectors appended one another as

index($list, $value) Returns the position of a value within a list. If the value isn’t found, returns null instead

feature_exists($feature) Returns whether a feature exists in the current Sass runtime. The

call($name, $args...) Dynamically calls a function. This can call user-defined functions, built-in functions, or plain CSS

str_insert($string, $insert, $index) Inserts $insert into $string at $index.

str_length($string) Returns the number of characters in a string.