convert.css

@import url(https://fonts.googleapis.com/css?family=Open+Sans);

html,body {
  height: 100%;
}

body {
  margin: 0;
  background-color: #dfdfdf;
  font-family: 'Open Sans', sans-serif;
}

fieldset {
  border: 0;
}

.wrapper{
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100%;
}

.page{
  max-width: 570px;
  background: rgba(250,250,250,.9);
  padding: 10px 20px;
  box-shadow: 4px 4px 10px rgba(0,0,0,.5);
  border-radius: 2px;
}

canvas {
  display: block;
  margin: auto;
}

.fork {
  position: absolute;
  top: 0;
  right: 0;
  border: 0;
}


.download {
  text-align: center;
}

.btn {
    border: 1px solid #B0C3D8;
    border-radius: 2px;
    background-color: #E0E9FD;
    padding: 4px 6px;
    text-decoration: none;
    color: #000;
}

.btn:hover {
  background-color: #E0F3F9;
}