Home/ Questions/Q 9136561
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-06-17T08:58:08+00:00

I have the following less compile error. My less is below not sure what

  • 0

I have the following less compile error. My less is below not sure what is causing this.

undefined_methodError: error evaluating function `darken`: Object #<Object> has no method 'toHSL' in /Users/anderskitson/Sites/mrskitson.ca/wp-content/themes/wordpress-bootstrap/library/less/variables.less:164:34
163 @navbarBackground:                "../images/nav.png";
164 @navbarBorder:                    darken(@navbarBackground, 12%);
165

(This action was triggered by a change to navbar.less)

Less File

@navbarBackground: "../images/nav.png";
background: url("{@navbarBackground}");
Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    From the fine manual:

    darken

    Decrease the lightness of a color by an absolute amount.

    Parameters:

    • color: A color object.
    • amount: A percentage 0-100%.

    Returns: color

    The darken function wants a color but your @navbarBackground is a URL for a background image. You’re getting a complaint about toHSL because LESS is trying to convert the color to the HSL format to make the darkening computation easier.

    I don’t know of any way to darken an image through LESS, you might need to manually darken the image and switch between them as needed.

    • 0