In-browser colour generator

// press Ctrl + Shift + J or Cmd + Opt + C and paste this in the console.
// alternatively, paste the following code in your address bar with "javascript:" in front, without these comments.
// you can save a bookmark in a similar format. ("javascript:" + code given below)
// use Right click + copy image and paste it into your art programme's canvas.
// click the square to remove it.

var dec=Math.floor(Math.random()*16777216);
var colour = dec.toString(16);
var zeros="";
for(i=0;i<6-colour.length;i++) {zeros+="0";};
colourName="#"+zeros+colour;
existingCanvas=document.getElementById("myCanvas");
if(existingCanvas!=undefined){
document.body.removeChild(existingCanvas);
}
document.body.innerHTML+="<canvas id='myCanvas' style='position:fixed;top:0px;left:0px;width:300px;height:300px;' onclick='this.style.left=\"5000px\"';/>";
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
ctx.fillStyle=colourName;ctx.fillRect(0,0,300,300);