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<div id="pelangi">
    <ul>
        <li><a href="URL" style="background-color: firebrick;"><strong>Início</strong></a></li>
        <li><a href="URL" style="background-color: red;"><strong>Blogger</strong></a></li>
        <li><a href="URL" style="background-color: orangered;"><strong>CSS</strong></a></li>
        <li><a href="URL" style="background-color: darkorange;"><strong>HTML</strong></a></li>
        <li><a href="URL" style="background-color: orange;"><strong>Gadgets</strong></a></li>
        <li><a href="URL" style="background-color: gold;"><strong>JavaScript</strong></a></li>
        <li><a href="URL" style="background-color: forestgreen;"><strong>Tutoriais</strong></a></li>
        <li><a href="URL" style="background-color: darkgreen;"><strong>Índice</strong></a></li>
        <li><a href="URL" style="background-color: dodgerblue;"><strong>Comentários</strong></a></li>
        <li><a href="URL" style="background-color: blue;"><strong>Forums</strong></a></li>
        <li><a href="URL" style="background-color: mediumslateblue;"><strong>Sociais</strong></a></li>
        <li><a href="URL" style="background-color: violet;"><strong>Sobre</strong></a></li>
        <li><a href="URL" style="background-color: darkviolet;"><strong>Contato</strong></a></li>
    </ul>
</div>

<div id="pelangi">
    <ul>
        <li><a href="URL" style="background-color: firebrick;"><strong>Início</strong></a></li>
        <li><a href="URL" style="background-color: red;"><strong>Blogger</strong></a></li>
        <li><a href="URL" style="background-color: orangered;"><strong>CSS</strong></a></li>
        <li><a href="URL" style="background-color: darkorange;"><strong>HTML</strong></a></li>
        <li><a href="URL" style="background-color: orange;"><strong>Gadgets</strong></a></li>
        <li><a href="URL" style="background-color: gold;"><strong>JavaScript</strong></a></li>
        <li><a href="URL" style="background-color: forestgreen;"><strong>Tutoriais</strong></a></li>
        <li><a href="URL" style="background-color: darkgreen;"><strong>Índice</strong></a></li>
        <li><a href="URL" style="background-color: dodgerblue;"><strong>Comentários</strong></a></li>
        <li><a href="URL" style="background-color: blue;"><strong>Forums</strong></a></li>
        <li><a href="URL" style="background-color: mediumslateblue;"><strong>Sociais</strong></a></li>
        <li><a href="URL" style="background-color: violet;"><strong>Sobre</strong></a></li>
        <li><a href="URL" style="background-color: darkviolet;"><strong>Contato</strong></a></li>
    </ul>
</div>

#pelangi             {font:normal 14px Trebuchet MS,Arial,Sans-Serif;margin:0 0 50px;}
#pelangi ul          {list-style-type: none;margin:10px 0;padding:0;height:95px;}
#pelangi a strong    {position:relative;top:40%;overflow:hidden;}
#pelangi li a        {width:85px;height:85px;display:inline-block;float:left;-webkit-border-radius:100px;-moz-border-radius:100px;border-radius:100px;text-align:center;}
#pelangi li a:link,
#pelangi li a:visited,
#pelangi li a:active {font-weight:bold;color:#FFFFFF;text-decoration:none;margin:2px 2px;}
#pelangi li a:hover  {margin:0 0;width:99px;height:99px;opacity:0.9;}