Edit Bootstrap Less or Sass files in a Visual Studio web project

Setup the Visual Studio Web Compiler to compile the Bootstrap Less or Sass styles.
Edit Less or Sass Files
This will work with either the Bootstrap Less or Sass files. The following sample uses Less files.

Use the NuGet package manager to load the Bootstrap and Bootstrap Less package into the web project.

1. Delete the Bootstrap css files from the Content folder.

2. Create an empty Bootstrap.less file in the Content folder and drag the /Content/Bootstrap/Bootstrap.less file into the new empty file.

This will create the import line as follows:
 
@import "bootstrap/bootstrap";
 
Install and use the Visual Studio Web Compiler to compile your LESS/SASS files
Compile the new Bootstrap.less file with the Visual Studio extension tool "Web Compiler".

Now you should be able to edit the variables.less file to change colors or other styles for your website.

Note: If you get an error in Utilities.less then add the line @import "mixin.less";