JSFiddle - React, Tailwind, and code Playground

HTML

<div class="navbar-form navbar-left">
    <div id="searchResults">So much results...</div>
    <input class="form-control" placeholder="Search..." type="text" autocomplete="off"  id="autocomplete_search" />
      
 </div>

CSS

*
{
    -webkit-box-sizing: border-box; 
	-moz-box-sizing: border-box;    */
	box-sizing: border-box;         
}
.navbar-form
{
    position: relative;
    
    /* just a little demo */
    margin-left:200px;
}

.form-control
{
    width: 100%;
}

#searchResults
{
    position: absolute;
    width: auto; 
    background: white;
    border-bottom-left-radius: 10px;
    border-bottom-right-radius: 10px;
    max-height: 200px;
    overflow-y: auto;
    
    border: 1px solid gray;
    
    /*This is relative to the navbar now*/
    left: 0;
    right: 0;
    top: 20px;
}