How can stop trails when mouse don't move or mouse get inside other container React js

Question

I have built a mouse trails its starts when the mouse moves but I did not know how can hide the trails when the mouse stop I will leave a link similar to what I built. Link: codepen.io/paulholmes/pen/wPLqPw

Answer 1

// dots is an array of Dot objects,
// mouse is an object used to track the X and Y position
   // of the mouse, set with a mousemove event listener below
var dots = [],
    mouse = {
      x: 0,
      y: 0
    };

// The Dot object used to scaffold the dots
var Dot = function() {
  this.x = 0;
  this.y = 0;
  this.node = (function(){
    var n = document.createElement("div");
    n.className = "trail";
    document.body.appendChild(n);
    return n;
  }());
};
// The Dot.prototype.draw() method sets the position of 
  // the object's <div> node
Dot.prototype.draw = function() {
  this.node.style.left = this.x + "px";
  this.node.style.top = this.y + "px";
};

// Creates the Dot objects, populates the dots array
for (var i = 0; i < 50; i++) {
  var d = new Dot();
  dots.push(d);
}

// This is the screen redraw function
function draw() {
  // Make sure the mouse position is set everytime
    // draw() is called.
  var x = mouse.x,
      y = mouse.y;
  x = x + 125; // to make dots little bit far from cursor
  // This loop is where all the 90s magic happens
  dots.forEach(function(dot, index, dots) {
    var nextDot = dots[index + 1] || dots[0];
    
    dot.x = x;
    dot.y = y;
    dot.draw();
    x += (nextDot.x - dot.x) * .6;
    y += (nextDot.y - dot.y) * .6;

  });
}
 (function (mouseStopDelay) {
        var timeout;
        document.addEventListener('mousemove', function (e) {
            clearTimeout(timeout);
            timeout = setTimeout(function () {
                var event = new CustomEvent("mousestop", {
                    detail: {
                        clientX: e.clientX,
                        clientY: e.clientY
                    },
                    bubbles: true,
                    cancelable: true
                });
                e.target.dispatchEvent(event);
            }, mouseStopDelay);
        });
    }(1700));

addEventListener("mousemove", function(event) {
  //event.preventDefault();
  mouse.x = event.pageX;
  mouse.y = event.pageY;
});
addEventListener("mousestop", function(event) {
  // You can hide or get the dots far from the cursor when mouse is stop mouving
  mouse.x = 0;
  mouse.y = 0;
});

// animate() calls draw() then recursively calls itself
  // everytime the screen repaints via requestAnimationFrame().
function animate() {
  draw();
  requestAnimationFrame(animate);
}

// And get it started by calling animate().
animate();

* {
   background: black;
}
.trail { /* className for the trail elements */
    position: absolute;
    height: 10px; width: 10px;
    border-radius: 50%;
    background: red;
    box-shadow: 1px 1px 4px 1px lightblue;
  }