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                <!-- Unsemantic, inaccessible button -->
<span class="btn btn--blue" onclick="alert('This is an inaccessible span masquerading as a button!')">Click me!</span>

<!-- Unsemantic, but screen reader accessible button -->
<span class="btn btn--red" tabindex="0" role="button" onclick="alert('This is a span made accessible to a screen reader but still doesn\'t work with a keyboard!')">Click me!</span>

<!-- Unsemantic, but screen reader/keyboard accessible button -->
<span class="btn btn--purple" tabindex="0" role="button" onclick="alert('Ugh this works but it is a terrible solution!')" onkeypress="alert('Ugh this works but it is a terrible solution!')">Click me!</span>

<!-- Classic semantic button -->
<button class="btn btn--green" onclick="alert('This is a proper button with default focus style.')">Click me!</button>



                body {
  font-size: 112.5%;

.btn {
  display: inline-block;
  border: .1rem outset;
  font-family: 'Rubik', sans-serif;
  font-size: 1.3rem;
  font-weight: normal;
  margin: 3rem;
  padding: .5rem 1rem;
  background: white;

.btn--green {
  color: #181;
  border-color: #181;

.btn--green:focus {
  background-color: #efe;

.btn--red {
  color: #922;
  border-color: #922;

.btn--red:focus {
  background-color: #fee;

.btn--blue {
  color: #229;
  border-color: #229;

.btn--blue:hover {
  background-color: #eef;

.btn--purple {
  color: rebeccapurple;
  border-color: rebeccapurple;

.btn--purple:focus      {
  background-color: #edf;

*:focus {
   outline: .15rem dashed hotpink;
  outline-offset: .2rem;

/* the below code is an override for default firefox button outline style */

button::-moz-focus-inner {
  border: 0;