src/add.svg

<?xml version="1.0" encoding="utf-8"?>
<!-- Generator: Adobe Illustrator 24.0.3, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
<svg version="1.1" id="icon" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
	 width="32px" height="32px" viewBox="0 0 32 32" style="enable-background:new 0 0 32 32;" xml:space="preserve">
<style type="text/css">
	.st0{fill:none;}
</style>
<polygon points="17,15 17,8 15,8 15,15 8,15 8,17 15,17 15,24 17,24 17,17 24,17 24,15 "/>
<rect class="st0" width="32" height="32"/>
</svg>