[TYPO3-english] Bootstrap style editing - system not responding. V6.2.6.

[Howard]

Hello

Right now I am just trying to change the base font size - 
@font-size-base [plugin.bootstrap_package.settings.less.font-size-base]

When trying to edit the bootstrap styles, Typo3 just hangs.
Template > Constant Editor > Bootstrap Package: Styling

I don't see any errors in my Apache log

Also, please would someone point me to the where the actual css is kept,
I tried ext/bootstrap_package/Resources/variables.less but to no avail.

( Introduction package - bootstrap , 6.2.6 on Linux Centos )

Thanks