JS1k: The JavaScript code golfing competition

c=document.getElementById('c');W='width';H='height';with(Math){with(c.getContext('2d')){R=random;r=function(){c[W]=innerWidth;c[H]=innerHeight;L=[]};r();addEventListener('resize',r,0);O=function(){return{x:c[W]*R(),y:c[H]*R(),z:3,s:'#'+ceil(R()*0xffffff).toString(16)}};setInterval(function(){fillStyle='rgba(0,0,0,.02)';fillRect(0,0,c[W],c[H]);if(L.length<c[H])L.push(O());L.forEach(function(o){with(o){lineWidth=z;strokeStyle=s;beginPath();moveTo(x,y);x+=18*R()-9;y+=18*R()-9;lineTo(x,y);stroke();z=min(max(z+R()-.5,1),30)}})},40)}}document.write("<style>*{margin:0;background:#000;position:absolute}</style>")

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