.center {
    margin: 0 auto;
    /* border: 3px solid green;
    padding: 10px; */
}

#sketch-holder-centered {
  /* background-position: center; */
  width: 500px;
  margin: 0 auto;
}

.main {
  background: #ff0;
  margin: 20px 0;
  padding: 10px;
}

.center {
  margin: 0 auto;
  width: 200px;
  background: black;
  padding: 20px;
  color: white;
}