title: What is the best practise to overwrite css from theme in drupal?
body: <p>I'm using drupal 8 and I have to customize already existing theme (downloaded from drupal site).</p>
  
  <p>Should I just make changes in specific files in docroot/themes/theme_name or do I have to create subdirectory somewhere in docroot/sites and there put the files that I wanted to change? I mean make there files with css styling that I want to change.</p>