JSFiddle - React, Tailwind, and code Playground
HTML
<form role="search" method="get" class="search-form" action="<?php echo home_url( '/' ); ?>">
<label>
<span class="screen-reader-text">Search for:</span>
<input type="search" class="search-field" placeholder="Search up in hur" value="" name="s" title="Search for:" /><input type="submit" class="search-submit" value="Search" />
</label>
</form>
CSS
.search-field, .search-submit{
margin:0;
}
.search-field + .search-submit{
border:1px solid #a9a9a9;
border-left:0px;
height:22px;
}