We're going to learn how to customize our cursor using only HTML, CSS and JS. It's pretty simple to customize the cursor.

HTML

Select the cursor

<div class="cursor"></div>

CSS

Step 1 - First make the cursor disappear. Using universal selector.

* {
  cursor: none;
}

Step 2 -

Select the cursor and apply some style on it

.cursor {
    z-index: 999; // as high as you want it because we don't want our content to overlap our cursor
    position: fixed; 
    background: #2696e8;
    width: 1em;
    height: 1em;
    border-radius: 50%; 
    pointer-events: none;
    animation: colors 5s infinite;
    transform: translate(-50%, -50%);
    display: none;
}

Step 3 -

Add keyframes

@keyframes colors {
    0% {
        filter: hue-rotate(0deg);
    }
    100% {
        filter: hue-rotate(360deg);
    }
}

Step 4 -

Now's the time for our cursor to be better. Using pseudo element.

.cursor:before {
    content: "";
    position: absolute;
    background: #2696e8;
    width: 36px;
    height: 36px;
    opacity: 0.2;
    transform: translate(-30%, -30%);
    border-radius: 50%;
}

JavaScript

Our cursor won't be going places without the help of JavaScript, sadly it can't be CSS only.

const cursor = document.querySelector(".cursor");
var timeout;

//follow cursor on mousemove
document.addEventListener("mousemove", (e) => {
    let x = e.pageX;
    let y = e.pageY;

    cursor.style.top = y + "px";
    cursor.style.left = x + "px";
    cursor.style.display = "block";

    //cursor effects when mouse stopped
    function mouseStopped() {
        cursor.style.display = "none";
    }
    clearTimeout(timeout);
    timeout = setTimeout(mouseStopped, 1000);
});