variable_exists($name) Check whether a variable with the given name exists in the current scope or in the global scope.

unique_id Returns a unique CSS identifier. The identifier is returned as an unquoted string. The identifier returned is only

opacify($color, $amount) Also known as: fade_in Makes

selector_unify($selector1, $selector2) Unifies two selectors into a single selector that matches only elements matched by

selector_nest($selectors...) Return a new selector with all selectors in $selectors nested beneath one another

opacity($color) Returns the alpha component (opacity) of a color. This is 1 unless otherwise specified.

ie_hex_str($color) Converts a color into the format understood by IE filters.

floor($number) Rounds a number down to the previous whole number.

selector_replace($selector, $original, $replacement) Replaces all instances of $original with $replacement

abs($number) Returns the absolute value of a number.