How to correctly add my less file to Magento 2?

Question

1. Create theme app/design/frontend/Vendorname/default
2. Try add my.less file for impot, or add code with new class and style to _extends.less to app/design/frontend/Vendorname/default/web/css/sourse.
3. rm -rf pub/static/*
4. rm -rf var/view_preprocessed/*
5. php /var/www/html/bin/magento cache:clean
6. php /var/www/html/bin/magento setup:static-content:deploy
7. php /var/www/html/bin/magento cache:clean

But this not work. I read a lot, but I do not see a particular decision. Please write how to correctly add less file to Magento 2? Please help.

Answer 1

We can import by using @import or @magento_import directive

1) The @import directive rules of usage

@import 'your_custom.less';

2) The @magento_import directive - must be commented out with two slashes

//@magento_import 'your_custom.less';

For example: your_custom.less is under app/design/frontend/Vendor/Theme/web/css/source/

-app/design/frontend/Vendor/Theme/web/css/source/_extend.less

@import 'your_custom.less';

You can read more here: http://devdocs.magento.com/guides/v2.1/frontend-dev-guide/css-topics/css-preprocess.html