JSFiddle - React, Tailwind, and code Playground

HTML

<script type="text/javascript"> 
window.onload=function() { attachBehaviors(); } 
function attachBehaviors() { 
 // only doing one here, but you can add others 
 if ( 
 document.getElementById('toggle_chk') && 
 document.getElementById('my_img') 
 ) { 
 // So JS is "aware" of the element style 
 document.getElementById('my_img').style.display='block'; 
 // Attach the behavior 
 document.getElementById('toggle_chk').onclick=function() {  
 toggle_image(this);  
 }; 
 } 
} 
// 
function toggle_image(chk) { 
 // already checked for my_img 
 // if you want to hide it . . .  
 //document.getElementById('my_img').style.display=(chk.checked)?'block':'none'; 
 // if you just want to swap src 
var src=(chk.checked)?'http://i.imgur.com/Ms79t.jpg':'http://i.imgur.com/PHSf5.jpg'; 
document.getElementById('my_img').src=src; 
} 
</script> 
</head> 
<body> 
<form action=""> 
<p><input type="checkbox" name="toggle_chk" id="toggle_chk" value="1" checked> 
<label for="toggle_chk">Mudar imagem</label></p> 
<p><img src="http://i.imgur.com/Ms79t.jpg" id="my_img"></p> 
</form> 
</body>