*{margin: 0; padding: 0; box-sizing: border-box;}
*::after{
  box-sizing: border-box;
}
*::before{
  box-sizing: border-box;
}
*{
  transition: all 0.3s;
}
body{
  display: flex;
  flex-direction: column;
  height: 100vh;
}
.code-wrapper{
  flex:1;
  height: 50%;
  padding: 10px;
}
.preview-wrapper{
  flex: 1;
  height: 50%;
}
#code{
  overflow: hidden;
  height: 100%;
}
.actions{
  position: absolute;
  right: 0;
  top: 0;
  display: flex;
  flex-direction: column;
}
.actions>button{
  margin: 10px;
  background: #ddd;
  padding: 8px 10px;
  border: none;
}
.actions>button.active{
  box-shadow: 1px 1px 1px rgba(0,0,0,0.8);
}
.actions>button:focus{
  outline: none;
}
.wrapper{
  width: 100%;
  height: 165px;
  position: relative;
}
.preview{
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
}