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CSS

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JavaScript

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HTML 

              
                <button
    id="notifications"
    class="notifications notifications--active"
    type="button"
>
    <span class="notifications__waves"></span>
    <span class="notifications__waves"></span>
    <span class="notifications__waves"></span>
    <span class="notifications__waves"></span>
    <span class="notifications__sr">Notifications</span>
    <span class="notifications__badge" data-badge>1</span>
</button>
!

CSS 

              
                * {
    border: 0;
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --hue: 223;
    --bg: hsl(var(--hue), 10%, 90%);
    --fg: hsl(var(--hue), 10%, 10%);
    font-size: calc(40px + (60 - 40) * (100vw - 320px) / (1280 - 320));
}

body,
button {
    color: var(--fg);
    font: 1em/1.5 "DM Sans", sans-serif;
}

body {
    background: var(--bg);
    height: 100vh;
    display: grid;
    place-items: center;
}

.notifications {
    background: transparent;
    box-shadow: 0 0 0 0.1em transparent;
    filter: brightness(1) grayscale(1);
    position: relative;
    width: 1.5em;
    height: 1.5em;
    transition: filter 0.15s 0.3s linear;
    -webkit-appearance: none;
    appearance: none;
    -webkit-tap-highlight-color: transparent;
}

.notifications:focus {
    outline: none;
}

.notifications:before,
.notifications:after,
.notifications__badge,
.notifications__waves,
.notifications__sr {
    position: absolute;
}

.notifications:before,
.notifications:after {
    content: "";
    display: block;
}

.notifications:before {
    background: radial-gradient(0.4em 0.4em at 50% 1.1em, hsl(38, 90%, 55%) 47%, hsla(38, 90%, 55%, 0) 50%);
    top: 0.2em;
    left: calc(50% - 0.2em);
    width: 0.4em;
    height: 1.3em;
    transform-origin: 50% 0.2em;
}

.notifications:after {
    background:
        /* rim */
        radial-gradient(0.4em 0.2em at 0.2em 1.2em, hsl(45, 90%, 55%) 46%, hsla(45, 90%, 55%, 0) 50%), linear-gradient(hsl(45, 90%, 55%), hsl(45, 90%, 55%)) 0.2em 1.1em / 1.1em 0.2em no-repeat, radial-gradient(0.4em 0.2em at 1.3em 1.2em, hsl(45, 90%, 55%) 46%, hsla(45, 90%, 55%, 0) 50%),
        /* middle */
        radial-gradient(1.2em 1.2em at 50% 0.75em, hsl(38, 90%, 55%) 49%, hsla(38, 90%, 55%, 0) 50%) 0 0 / 100% 75% no-repeat, linear-gradient(hsl(38, 90%, 55%), hsl(38, 90%, 55%)) 0.15em 0.75em / 1.2em 0.4em no-repeat,
        /* top */
        radial-gradient(0.3em 0.3em at 50% 0.15em, hsl(45, 90%, 55%) 48%, hsla(45, 90%, 55%, 0) 50%);
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    transform-origin: 50% 0.15em;
}

.notifications__badge {
    background: hsl(3, 90%, 55%);
    border-radius: 0.375rem;
    color: hsl(0, 0%, 100%);
    font-size: 0.5em;
    font-weight: bold;
    padding: 0 0.125rem;
    top: -0.125rem;
    right: -0.125rem;
    min-width: 0.75rem;
    height: 0.75rem;
    text-align: center;
    transition: transform 0.3s 0.15s ease-out;
    z-index: 1;
}

.notifications__badge:empty {
    transform: scale(0);
    transition-delay: 0s;
}

.notifications__waves,
.notifications--active:before,
.notifications--active:after {
    animation-duration: 2s;
    animation-timing-function: linear;
    animation-iteration-count: infinite;
}

.notifications__waves {
    animation-delay: 0.6s;
    border-top: 0.1em solid transparent;
    border-right: 0.1em solid hsla(var(--hue), 10%, 50%);
    border-bottom: 0.1em solid transparent;
    border-left: 0.1em solid hsla(var(--hue), 10%, 50%);
    border-radius: 50%;
    top: -50%;
    left: -50%;
    opacity: 0;
    pointer-events: none;
    width: 200%;
    height: 200%;
    transform: scale(0.3);
}

.notifications__waves:nth-child(2) {
    animation-delay: 0.75s;
}

.notifications__waves:nth-child(3) {
    animation-delay: 0.9s;
}

.notifications__waves:nth-child(4) {
    animation-delay: 1.05s;
}

.notifications--active {
    filter: brightness(1) grayscale(0);
    transition-delay: 0s;
}

.notifications--active:before,
.notifications--active:after {
    animation-delay: 0.3s;
}

.notifications--active:before {
    animation-name: ringBefore;
}

.notifications--active:after {
    animation-name: ringAfter;
}

.notifications--active .notifications__waves {
    animation-name: waves;
}

.notifications__sr {
    clip: rect(1px, 1px, 1px, 1px);
    overflow: hidden;
    width: 1px;
    height: 1px;
}

/* Dark theme */
@media (prefers-color-scheme: dark) {
    :root {
        --bg: hsl(var(--hue), 10%, 10%);
        --fg: hsl(var(--hue), 10%, 90%);
    }
}

/* Animations */
@keyframes ringBefore {
    from {
        transform: rotate(0);
    }

    15% {
        transform: rotate(-3deg);
    }

    20% {
        transform: rotate(6deg);
    }

    25% {
        transform: rotate(-6deg);
    }

    30% {
        transform: rotate(18deg);
    }

    35% {
        transform: rotate(-18deg);
    }

    40% {
        transform: rotate(22deg);
    }

    45% {
        transform: rotate(-20deg);
    }

    50% {
        transform: rotate(18deg);
    }

    55% {
        transform: rotate(-16deg);
    }

    60% {
        transform: rotate(14deg);
    }

    65% {
        transform: rotate(-12deg);
    }

    70% {
        transform: rotate(10deg);
    }

    75% {
        transform: rotate(-8deg);
    }

    80% {
        transform: rotate(6deg);
    }

    85% {
        transform: rotate(-4deg);
    }

    90% {
        transform: rotate(2deg);
    }

    95% {
        transform: rotate(-1deg);
    }
}

@keyframes ringAfter {

    from,
    40%,
    to {
        transform: rotate(0);
    }

    5%,
    35% {
        transform: rotate(10deg);
    }

    10%,
    30% {
        transform: rotate(-10deg);
    }

    15%,
    25% {
        transform: rotate(20deg);
    }

    20% {
        transform: rotate(-20deg);
    }
}

@keyframes waves {
    from {
        opacity: 1;
        transform: scale(0.3);
    }

    20%,
    to {
        opacity: 0;
        transform: scale(1);
    }
}
!

JS 

              
                window.addEventListener("DOMContentLoaded", () => {
    const n = new Notifications("#notifications");
});
class Notifications {
    constructor(qs) {
        this.el = document.querySelector(qs);
        this.badge = null;
        this.items = 0;
        this.timeout = null;
        this.init();
    }
    init() {
        if (this.el) {
            this.el.addEventListener("click", this.read.bind(this));
            this.badge = this.el.querySelector("[data-badge]");
            this.reset(1);
        }
    }
    read() {
        if (this.items > 0) {
            this.items = 0;
            this.el.classList.remove("notifications--active");
            this.badge.innerHTML = "";
            const items = this.random(1, 10, true);
            clearTimeout(this.timeout);
            this.timeout = setTimeout(this.reset.bind(this, items), 2e3);
        }
    }
    reset(items) {
        this.items = items;
        if (this.items > 0) {
            this.el.classList.add("notifications--active");
            this.badge.innerHTML = this.items;
        }
    }
    random(min, max, round = false) {
        const percent = crypto.getRandomValues(new Uint32Array(1))[0] / 2 ** 32;
        const relativeValue = (max - min) * percent;
        return (
            min +
            (round === true
                ? Math.round(relativeValue)
                : +relativeValue.toFixed(2))
        );
    }
}
!
999px

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