marble.css

.bacon-marble {
  padding: 1em;
  padding-bottom: 2em;
  padding-top: 0;
  width: 80%;
  margin-left: auto;
  margin-right: auto;
}
.bacon-input, .bacon-output {
  position: relative;
  padding: 0.5em;
  margin: 0.8em;
}
.bacon-output:before, .bacon-input:before {
  content: ' ';
  height: 2px;
  position: absolute;
  top: 85%;
  width: calc(100% + 20px);
  background-color: lightgray;
  z-index: 5;
}
.bacon-output:after, .bacon-input:after {
    content: '\25B6';
    color: lightgray;
    width: 20px;
    font-size: 20px;
    height: 20px;
    position: absolute;
    right: -40px;
    top: 22px;
}
.bacon-input span {
 z-index: 10;
}
.bacon-output span, .bacon-input span {
 font-weight: bold;
 background-color: #000080;
 color: white;
 font-family: "nexa bold", sans-serif;
 padding: 0.4em 0.9em;
 border-radius: 2em;
 margin: 0.5em;
}
.bacon-output span {
 background-color: #008000;
 z-index: 10;
}
.bacon-input:nth-child(2) span {
 background-color: #802000;
}
.bacon-label {
 color: #222;
 text-align: center;
 margin-bottom: 1em;
}
.bacon-label code {
 color: #222;
}
.bacon-output label, .bacon-input label {
  position: absolute;
  width: 4.5em;
  text-align: right;
  left: -5em;
  top: 60%;
}