<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8>
<style>
div { border: 1px solid silver; padding: 5px; writing-mode: sideways-lr; }
span { padding: 5px; color: transparent; }
span:nth-child(1) { background: red;    }
span:nth-child(2) { background: orange; }
span:nth-child(3) { background: yellow; }
span:nth-child(4) { background: green;  }
span:nth-child(5) { background: blue;   }
span:nth-child(6) { background: indigo; }
span:nth-child(7) { background: violet; }
</style>
</head>

<body>

<div><span>one</span> <span>two</span> <span>three</span> <span>four</span>
 <span>five</span> <span>six</span> <span>seven</span></div>