hsla($hue, $saturation, $lightness, $alpha) Creates a Color from hue, saturation, lightness

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

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

Defining a Mixin: @mixin Mixins are defined with the @mixin directive. It’s followed by the name of the mixin and

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

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

transparentize($color, $amount) Also known as: fade_out Makes

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

:nested Nested style is the default Sass style, because it reflects the structure of the CSS styles and the HTML document they’re

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