JSFiddle - React, Tailwind, and code Playground
HTML
<svg width="640" height="480" viewbox="0 0 640 480" xmlns="http://www.w3.org/2000/svg">
<title>Small red heart with transparent background</title>
<g>
<title>Layer 1</title>
<g id="layer1">
<path id="svg_2" d="m219.28949,21.827393c-66.240005,0 -119.999954,53.76001 -119.999954,120c0,134.755524 135.933151,170.08728 228.562454,303.308044c87.574219,-132.403381 228.5625,-172.854584 228.5625,-303.308044c0,-66.23999 -53.759888,-120 -120,-120c-48.047913,0 -89.401611,28.370422 -108.5625,69.1875c-19.160797,-40.817078 -60.514496,-69.1875 -108.5625,-69.1875z"/>
</g>
</g>
</svg>
CSS
svg{
display: block;
width: 50px;
height: auto;
}
#svg_2{
fill:transparent;
stroke:#ccc;
stroke-width:6px;
cursor:pointer;
transition:fill .3s;
}
#svg_2.filled{
fill:#ccc;
}
JavaScript
$('#svg_2').on('click', function(){
$(this).toggleClass('filled');
});