In this case you can escape this value which will make LESS skip it and move on. A (reference) import doesn’t do that. Assuming names didn’t change, I get the changes. The good news is that with the help of LESS we can! If you want to change the value of a color you can do so by subtracting or adding another color to it. Envato Tuts+ tutorials are translated into other languages by our community members—you can be involved too! This will import the CSS rules defined in reset.min.css without running them through the LESS parser. If we decide we'd rather go with Trebuchet MS as our heading font we don't need to go through our whole file, we just change the value of the variable. We can now use this variable whenever we want to use the Georgia font. Importing remote CSS files. variable @variable-x is undefined in file /var/www/magento2/var/view_preprocessed/css/adminhtml/Magento/backend/en_US/css/styles.less in styles.less on line 56, column 17, Conventional notations used in this Guide, Use Sass preprocessor and Gulp task runner, Simple ways to customize a theme's styles, Simple style changes with client-side LESS compilation vs. server-side, How to Make Your Theme Responsive and Mobile, Create a responsive mobile theme based on a default theme, Use translation dictionary to customize strings, Magento_Blank_theme_dir/web/css/styles-m.less, Magento_Blank_theme_dir/web/css/styles-l.less, Magento_Blank_theme_dir/web/css/print.less, http://lesscss.org/usage/#using-less-in-the-browser. But with this trick its pretty easy to use BEM, SuitCSS, or ACSS to define your components and just map them back to the more frameworky classes. You can also grab the code directly from the Github repository. I feel this way about grids from frameworks. I don't like CSS. If you decide on a different color after line 2,000 and then change your mind at line 3,567 it will be extremely difficult to ensure the right colors are used and the documentation is correct as well. That's a good thing! My favorite features of LESS have to do with color management. If you want to recolor the website and change the @color-button value to a green color not only does the background of the button change but the border also changes and becomes a deeper version of the green color. To include a .less file using the @magento_import directive: To avoid any conflicts with the original LESS syntax, @magento_import must be commented out with two slashes. LESS lets you import both CSS and LESS files with the following syntax: The first import is pretty obvious.