I'm using javascript to make an sparkle like animation with css.
<div class="r1">
<img src="star.png">
</div>
Each Dot
.dotter{
width: 4px;
height: 4px;
background: blue;
border-radius: 50px;
position: absolute;
bottom: 50%;
left: 50%;
transform: translate(0,0);
}
Javascript
const block = document.querySelector('.r1');
const css = document.createElement('style');
function creator(){
var newKey = new String;
for(i=0;i<=100;i++){
var dot = document.createElement('div');
dot.classList.add('dotter');
dot.style.animation = `fadeOut${i} 1s linear infinite`;
var keyframes = `@keyframes fadeOut${i} {from {transform: translate(0,0) scale(1);opacity: 1;}to {transform: translate(${newRandom()[0]}%,${newRandom()[1]}%) scale(0.1);opacity: 0;}}`;
block.appendChild(dot);
newKey += keyframes;
}
css.innerText = newKey;
document.getElementsByTagName('body')[0].appendChild(css);
};
creator();
function newRandom(){
const n1p1 = Math.random()*900;
const n1p2 = Math.random()*(-900);
const n2p1 = Math.random()*(-900);
const n2p2 = Math.random()*900;
const n1 = Math.random() < 0.5 ? n1p1 : n1p2;
const n2 = Math.random() < 0.5 ? n2p1 : n2p2;
const m1 = Math.abs(n1);
const m2 = Math.abs(n2);
if( m1>=850 || m2>850 ){
if((m1 + m2) >= 900){
return [n2,n1];
}else{
return newRandom();
}
}else{
return newRandom();
}
};
Now the problem is when I run the code, the sparkles end-up forming a square outside the image, I need a numeric solution for how to make the sparkles end-up shaping a circle.

I changed yout NewRandom() function to achieve this, if helps
const blocks = document.querySelectorAll('.r');
const css = document.createElement('style');
function creator() {
var newKey = new String;
blocks.forEach(function(block) {
for (i = 0; i <= 100; i++) {
var dot = document.createElement('div');
dot.classList.add('dotter');
dot.style.animation = `fadeOut${i} 1s linear infinite`;
var keyframes = `@keyframes fadeOut${i} {from {transform: translate(0,0) scale(1);opacity: 1;}to {transform: translate(${newRandom()[0]}%,${newRandom()[1]}%) scale(0.1);opacity: 0;}}`;
block.appendChild(dot);
newKey += keyframes;
}
});
css.innerText = newKey;
document.getElementsByTagName('body')[0].appendChild(css);
};
creator();
function newRandom() {
const angle = Math.random() * 360;
const dist = Math.random() * 2000;
const x = Math.cos(angle) * dist;
const y = Math.sin(angle) * dist;
return [x, y];
};
.dotter {
width: 4px;
height: 4px;
background: blue;
border-radius: 50px;
position: absolute;
transform: translate(0, 0);
}
<div class="r">
<img src="star.png">
</div>
<br><br><br><br><br>
<div class="r">
<img src="star.png">
</div>