<a class="link" href="">Anasayfa</a>
.link 
{
  text-decoration:none;
  position:relative;
}
.link::before 
{
  content:'';
  position:absolute;
  left:0;
  bottom:0;
  width:0px;
  height:3px;
  background:#000;
  opacity:0;
  -webkit-transition: width 2s; /* Safari */
    transition: width 2s;
}

.link:hover:before
{
  opacity:1;
  width:100%;
}

External CSS

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External JavaScript

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