h2#danraku2{
   position: relative;
  padding: 0.6em;
  background: #e0edff;
  }
　h2#danraku2:after {
   position: absolute;
   content: '';
   top: 100%;
   left: 30px;
border: 15px solid transparent;
border-top: 15px solid #e0edff;
width: 0;
height: 0;
   }