I'm using components/bootstrap bundle in my symfony2 project by composer to provide bootstrap. The less files are in /verdor/components/bootstrap/less/ and it will automatically make copies (maybe links?) to /web/components/bootstrap/less/
So, what is the correct way to do it if I want to make some changes to variables.less ?
Is there any way put my own variables.less file in /app/ folder like overriding twig templates?
You may take a look at the LESS structure used by bootswatch to customize bootstrap LESS files (https://github.com/thomaspark/bootswatch/)
Namely,