<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<div class="container">
<div class="row justify-content-center mt-5 mr-0">
<div class="col-12 col-md-10 col-lg-8">
<form class="card card-sm">
<div class="card-body row no-gutters align-items-center">
<div class="col-auto">
<i class="fas fa-search h4 text-body"></i>
</div>
<div class="col">
<input class="form-control form-control-borderless src_fild" type="search" placeholder="Search topics or keywords">
</div>
<div class="col-auto">
<button class="btn btn-lg btn-success src_btn" type="submit">Search</button>
</div>
</div>
</form>
</div>
</div>
</div>
