Варлам Ерофеич

<nav class="prost"> 
  <a href="http://indexru.html"     rel="nofollow">Раздел 1</a>&nbsp;
  <a href="http://uslugi.html"      rel="nofollow">Раздел 2</a>&nbsp;
  <a href="http://kontaktru.html"   rel="nofollow">Раздел 3</a>&nbsp;
  <a href="http://about.html"       rel="nofollow">Раздел 4</a>&nbsp;
</nav>

.prost{
       margin: 1px; 
       padding: 8px; 
       text-align: center; 
       background: rgba(150, 200, 210, .8); 
      }

.box {
    margin: 1rem;
    width: 15rem;
    height: 15rem;
    box-sizing: border-box;
    text-align: center;
    vertical-align: center;
  border: 6.5rem solid transparent;
  border-image: radial-gradient(#bcc, #888 30%, 
        #e62 50%, #2cc, #828 69%, transparent 72%) 10% fill;
}