Center the demo

dabblet.css

div {	
width: 280px;	
height: 280px;	
background: #1e90ff;	
-webkit-clip-path: polygon(100% 51%, 96% 40%, 89% 29%, 80% 21%, 69% 13%, 57% 6%, 45% 3%, 30% 9%, 19% 14%, 8% 24%, 2% 34%, 0% 49%, 0% 62%, 4% 73%, 13% 84%, 24% 91%, 33% 97%, 44% 99%, 46% 89%, 55% 87%, 65% 86%, 76% 82%, 84% 75%, 92% 67%, 98% 58%);
clip-path: polygon(100% 51%, 96% 40%, 89% 29%, 80% 21%, 69% 13%, 57% 6%, 45% 3%, 30% 9%, 19% 14%, 8% 24%, 2% 34%, 0% 49%, 0% 62%, 4% 73%, 13% 84%, 24% 91%, 33% 97%, 44% 99%, 46% 89%, 55% 87%, 65% 86%, 76% 82%, 84% 75%, 92% 67%, 98% 58%);}
/* Center the demo */
html, body { 
height: 100%; 
}
body {	
display: flex;	
justify-content: center;	
align-items: center;
}

dabblet.html

<div></div>

dabblet.js

// alert('Hello world!');

settings.json

{"view":"split","fontsize":"100","seethrough":"","prefixfree":"1","page":"all"}