percentage($number) Converts a unitless number to a percentage.

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

join($list1, $list2, $separator:auto) Joins together two lists into one. Unless $separator

set Return a new list, based on the list provided, but with the nth element changed to the value given.

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

grayscale($color) Converts a color to grayscale. This is identical to desaturate(color, 100%).

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

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

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

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