When running Grunt from a DOS prompt in the source directory (in my case \inetpub\wwwroot\YAFNET_3.2.5_source\yafsrc\YetAnotherForum.NET) I'm getting the following error:

Running "sass:installWizard" (sass) taskError:

Undefined variable: "$card-cap-bg".   on line 19 of Content/bootstrap/_card.scss   from line 29 of Content/bootstrap/bootstrap.scss   from line 1 of Content/InstallWizard.scss  Use --trace for backtrace.Warning: Exited with error code 13 Use --force to continue.

The only .scss file I've made any changes to is YAFNET_3.2.5_source\yafsrc\YetAnotherForum.NET\Content\bootstrap\_variables.scss

Any ideas what the problem is?

Edit: This also occurs if I run grunt from within Visual Studio.

BWG

I overwrote the  _variables.scss with the one in the sourcecode package and then reapplied my changes. It now works, so clearly the error was on my side, although I couldn't see what the problem was. (I can now run grunt tasks within VS too)