title: How do we detect and change styles at runtime?
body: <p>It's cool that Delphi XE3 and below have styles for our applications. But I've noticed that we can mark as many styles as we want and them choose which of them to use as default.</p>
  
  <p>It means that we could change styles at will, but how to do it in code? And how to let the user choose which style to use in our software? </p>