title: git error: failed to push some refs to remote
body: <p>I can't push now, though I could do it yesterday.</p>
  <p>When I use <code>git push origin master</code>, I get an error:</p>
  <pre><code>$ git remote -v
  origin  https://github.com/REDACTED.git (fetch)
  origin  https://github.com/REDACTED.git (push)
  
  $ git push origin master
  Username for 'https://github.com': REDACTED
  Password for 'https://REDACTED@github.com':
  To https://github.com/REDACTED.git
  ! [rejected]         master -&gt; master (non-fast-forward)
  error: failed to push some refs to 'https://github.com/REDACTED.git'
  hint: Updates were rejected because the tip of your current branch is behind
  hint: its remote counterpart. Integrate the remote changes (e.g.
  hint: 'git pull ...') before pushing again.
  hint: See the 'Note about fast-forwards' in 'git push --help' for details.
  </code></pre>
  <p>What my working directory and remote repository looks like:</p>
  <p><img src="https://i.stack.imgur.com/Sz17u.png" alt="Screenshot of Windows file folder with these directories: .git, css, js. And these files: index.php, readme, setsu.php. The word &quot;local&quot; with an arrow points to the css-folder. Below, screenshot with heading &quot;github&quot;, and a css-folder and index.php-file" /></p>