Hello. I want to change some styles in single module. I create own child theme for Snowdog and everything it's compiled by frontools.
Have you got some suggestion how i can do it?
And how we can change variables like font in theme? We cannot do it by include lib becouse i found only "lib-font-face" - we can't change font to another if we cannot change $font-family__base variable.
Sorry but I don't understand your issue.
Did you add a partial file to your child theme to overwrite default file? It works same for files with variables.
But at at there is no magic here (only inheritance, but it's super simple, just create a file with same path/name in child theme and you are ready to go), just follow SASS rules and you will be fine.
Remember that this tools and theme are designed and created for experienced Magento 2 front-end developers, if you are not this type of person, probably should stick with core solutions, study docs, learn about SASS and JS, then back here when you will fell familiar with it, read the code and docs, to get how it works.