<div class="esnekKutuKapsul">
    <div class="esnekKutu">Esnek Kutu1</div>
    <div class="esnekKutu">Esnek Kutu2</div>
    <div class="esnekKutu">Esnek Kutu3</div>
</div>

.esnekKutuKapsul{
  display: flex;
  width:90%;
  border:5px solid #006c8e;
  background: #009cc1;
  padding: 10px;
  font-family: arial;
}

.esnekKutu{
  background-color:#fff;
  text-align:center;
  padding: 70px 0;
  width:190px;
  margin-right:15px;
  font-size: 18px;
}

.esnekKutu:last-child{
  margin-right:0;
  background: #80cee0;
}

.esnekKutu:nth-child(2) {
  background:#ccebf3;
}