.maindiv{
    width: 200px;
    height: 40px;
    overflow: hidden;
    border: 1px solid black;
    border-radius: 3px;
    position: relative; 
  }
  .maindiv select{
    -webkit-appearance: none;
    -moz-appearance:none;
    -ms-appearance:none;
    appearance:none;
    width: 100%;
    height: 40px;
    border: none;
  }
  .maindiv select:focus{
    outline: none!important;
    
  }
  
  .maindiv:after {
      width: 0;
      height: 0;
      border-style: solid;
      border-width: 5px 5px 0 5px;
      border-color: #0d4781 transparent transparent transparent;
      position: absolute;
      right: 10px;
      content: "";
      top: 18px;
      pointer-event: none;
  }