title: Code behind Bootstrap native classes - where can I see it?
body: <p>I am studying Bootstrap classes to understand better how they work. Documentation is quite detailed and the working of each one is not difficult to understand. However, I would like to "see" which code each one of these classes (or at least the ones I am going to use) carry themselves.</p>
  
  <p>For example <code>.btn</code> class, when looked on Chrome DevTools-Source tab shows me that: </p>
  
  <pre><code>.btn {
    display: inline-block;
    font-family: $btn-font-family;
    font-weight: $btn-font-weight;
    color: $body-color;
    text-align: center;
    vertical-align: middle;
    user-select: none;
    background-color: transparent;
    border: $btn-border-width solid transparent;
    @include button-size($btn-padding-y, $btn-padding-x, $btn-font-size, $btn-line-height, $btn-border-radius);
    @include transition($btn-transition);
  </code></pre>
  
  <p>For me, it is useful because I can see all properties and then in some cases, debug something understanding what the native classes may be interacting with things in my code.</p>
  
  <p>I have been looking for a while and went through documentation, but although I find useful information about how to use the classes, I still can't find which code each one of them has inside.</p>
  
  <p>My question: is it possible to see inside these classes (like the <code>.btn</code> referred above other than via Developer Tools? If so, is there an index where I can see them all?</p>
  
  <p>Thanks in advance.</p>