style.css

html{
  height: 100%;
}
body{
  margin: 0;
  height: 100%;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.github{
  background-image: url(./github.svg), none;
  width: 15px;
  height: 15px;
  display: inline-block;
  vertical-align: middle;
  margin-right: 5px;
}
.col{
  width: 50%;
  display: flex;
  flex-direction: column;
  position: relative;
}
.header{
  width: 100%;
  padding: 10px;
  background: #fafafa;
  border-bottom: 1px solid #f5f5f5;
  font-family: "Helvetica Neue", helvetica, arial;
  box-sizing: border-box;
}
.header .title{
  display: inline-block;
}
.header .title .formula{
  margin-left: 15px;
  color: rgba(0,0,0,0.8);
  font-family: Monaco, Menlo, Courier;
  font-size: 12px;
}
.header a.button{
  color: rgba(0,0,0,0.8);
  text-decoration: none;
  padding: 4px 10px;
  font-size: 12px;
}
.dropdown{
  display: flex;
  flex-direction: column;
  text-align: center;
}
.dropdown .list-item{
  color: #7f94a1;
  font-size: 12px;
  text-decoration: none;
  padding: 4px 0;
  display: none;
  width: 80px;

}
.dropdown .list-item.selected{
  display: block;
}
.dropdown .list-item.visible{
  display: block;
}
.dropdown .list-item:hover{
  color: #b35e14;
}
.pull-right{
  float: right;
}
.content{
  width: 100%;
  height: 100%;
  display: flex;
  align-items: stretch;
  flex-direction: row;
}
.CodeMirror{
  border-bottom: 2px solid #f7f7f7;
  width: 100%;
  display: inline-block;
  box-sizing: border-box;
  flex-grow: 1;
  position: relative;
}

.col .label{
  text-decoration: none;
  text-transform: uppercase;
  color: #7f94a1;
  font-family: verdana;
  font-size: 12px;
  padding: 10px;
  background: rgba(255,255,255,0.7);
  z-index: 100;

}
.col .top{
  position: absolute;
  top: 0;
  right: 0;
}
.col .bottom{
  position: absolute;
  top: 50%;
  bottom: 0;
  right: 0;
}