<html><head> <style>div{height: 50px; margin: 0 auto;}.red{background-color: #ff0000; width: 30px;}.orange{background-color: #ffa500; width: 60px;}.yellow{background-color: #ffff00; width: 90px;}.green{background-color: #00ff00; width: 120px;}.blue{background-color: #0000ff; width: 150px;}.indigo{background-color: #4b0082; width: 180px;}.violet{background-color: #ee82ee; width: 210px;}</style></head><body> <div class="red"></div><div class="orange"></div><div class="yellow"></div><div class="green"></div><div class="blue"></div><div class="indigo"></div><div class="violet"></div></body></html>]]>