Don't forget to check the tutorial below!

If this was a job project, then I would be using something like tailwind, or css-in-js tied to a specific UI library (like Mantine), or at the very least SCSS modules. But since it's a personal website, which is also meant to be a source of educational tutorials, I decided to go with SCSS BEM classes, since they are 100% compatible with codepen, which makes changing/copypasting code very simple. Also, SCSS got the broadest appeal, since it doesn't require any specific library knowledge to read the code. But I am not promising that my styles will be easy to understand :)
This website is meant to showcase various experiments with fun animations and relatively new CSS features, but it is not intended to be a source of production-ready components with mobile responsiveness and proper accessibility. If you can easily copy-paste some of these components into your app, then I am happy for you, but generally don't expect same level of DX/UX polish similar to popular libraries with huge support behind them.
At my job I try to evade heavily commenting my code, but since this website is meant to be the source of learning materials about UI front-end, I decided to add a variety of comments where it might seem useful.

Twitter X Logo Transformation Tutorial

What is even happening here?

So first let's break down everything that is happening here in this chain of animations:

  1. Image of Smoking Elon appears with a short delay.
  2. Sweat teardrop appears on Twitter logo with a delay.
  3. Twitter logo is shaking.
  4. Twitter logo svg fill color animated to transparent with a delay.
  5. Black background circle is expanding from the center (while covering Elon's image) and Twitter logo is morphing into X left rectangle while changing stroke color to white.
  6. The second line in X logo is appearing from the center.
  7. Doge image appearing.
  8. Reset button appearing.

Now let's cover how all of this is done (spoiler - it's mostly just css transitions tied to single class and a little bit of JS to morph the logo).

Show me the code

Tutorials will mostly be covering a general overview of the implementation with a few code embeds here and there. Full code with comments is always available on github (linked below) and codepen.

Also, if reading SCSS code with parent references nesting is too much trouble, you can always check compiled CSS in codepen to see the final classes and styles.



Initial setup

One of the most important parts when dealing with sequential animations is to keep your sanity intact when trying to define the whole chain of events and assigning timings. Because once you'll start inevitable polishing phase, you will need to be able to easily change individual timings, without breaking anything and losing your mind.

That's why we gonna define our sequence of animations in javascript array and derive map from it with computed delays for each specific animation.

// this is our single source of truth for chain of animations timings, values are in seconds
const animations = [
  { name: 'elon-waiting', duration: 0.5 },
  { name: 'elon-appearance', duration: 1 },
  { name: 'twitter-reaction-waiting', duration: 0.3 },
  { name: 'twitter-reaction', duration: 0.7 },
  { name: 'twitter-shaking', duration: 1.4 },
  { name: 'logo-fill-waiting', duration: 0 },
  { name: 'logo-fill', duration: 0.1 },
  { name: 'logo-morphing', duration: 0.2 }, // this step combines black background circle expansion and twitter logo morphing with stroke color change
  { name: 'x-part-2', duration: 0.6 },
  { name: 'doge-appearance', duration: 0.3 },
  { name: 'reset-appearance', duration: 0.3 },

// this map also contains delays for each animation, which makes our css transitions code very trivial
const { acc: animationsWithDelaysMap } = animations.reduce(
  ({ acc, delay }, anim) => {
    acc[] = anim.duration;
    acc[`${}-delay`] = delay;
    return {
      acc, // accumulates animation durations and their respective delays
      delay: delay + anim.duration, // accumulates total delay
  { acc: {} as Record<string, number>, delay: 0 }

And then we gonna assign these variables to our main container, so that CSS could access them:

const styleObj = {
  '--logo-size': `${logoSize}px`,
    (acc, [name, duration]) => {
      // the final result is something like { '--doge-appearance-at': '0.3s', '--doge-appearance-delay': '1.5s' }
      acc[`--${name}${name.endsWith('delay') ? '' : '-at'}`] = `${duration}s`;
      return acc;
    {} as Record<string, string>
} as React.CSSProperties;

// main container in JSX
<div className="...classnames" style={styleObj}>

After that we'll need to put all our required elements and assets in JSX. Here is how it looks (classnames should be self-explanatory):

  className={cn('twitter-x', { 's--morphing': isMorphing })}
  <div className="twitter-x__center">
    <div className="twitter-x__logo">
    {/* I'm using tabler icons which are based on 24x24 viewBox,
    so values for things like stroke are relative to that original size */}

      {/* Second part of X logo, the line from bottom-left corner to top-right.
      But actually it's 2 lines in our case. Painted with numbers :) */}
      <svg viewBox="0 0 270 270" className="twitter-x__logo-svg2">
        <path d="M-20,280 0,280 122,153 102,150z" />
        <path d="M250,-10 270,-10 160,115 150,100z" />

      {/* I'm nesting it in a container so that I could hide svg droplet later with separate transition, without using second class */}
      <div className="twitter-x__sweat">
        <IconDropletFilled size={24} />
      alt="Elon Smoking"
    <div className="twitter-x__black-bg" />
    <IconRefresh className="twitter-x__reset" onClick={onReset} />

All of our elements are located in .twitter-x__center which is a centered (duh) 270x270 container. Twitter logo positioned inside and takes parent's dimensions, while other assets are positioned with position: absolute somewhere around it.

For the full styles and code check the source links above, I will be showing only parts of styles for specific elements below.

Elon and sweating bird

With Elon everything is simple, I googled "elon smoking weed transparent background" and got like second image, optimized it on tinypng and uploaded it to imgur. It appears with a short delay via basic opacity change.

.twitter-x__elon {
  // other styles
  opacity: 0;
  will-change: opacity;

  @include isMorphing {
    transition: opacity var(--elon-appearance-at) var(--elon-appearance-delay);
    opacity: 1;

It is important to note that in this demo transition and animation rules are always defined in state class rule and not on the root level of the element. This way transition will be happening only when class is applied. This allows us to remove .s--morphing class and reset the whole state of UI instantly, without looking at reverse transitions.

The bird sweat droplet is animated pretty much the same way, the only difference is that there is also translateY change to make it appear from the top. And nesting svg in container allows me to hide it later with a separate transition, without using second class.

.twitter-x__sweat {
  --timing: var(--twitter-reaction-at) var(--twitter-reaction-delay);
  // other styles
  transform: translateY(-10px);
  opacity: 0;
  will-change: opacity, transform;

  @include isMorphing {
    transition: opacity var(--timing), transform var(--timing);
    transform: translateY(0);
    opacity: 1;

Shaking bird

For shaking animation we are using SCSS loop to make random values (which are generated once during styles compilation) for transform: translate (both X and Y values) in keyframes animation, which just rapidly shifts element around its original place.

// scss generates random values on compilation which are allowing us to make it look like a random shaking,
// by rapidly shifting element vertically and horizontally
@keyframes shaking {
  @for $i from 0 through 50 {
    #{$i * 2%} { // interpolated results are 0%, 2%, ... 98%, 100%
      // (random(20) - 10) * 1px is a random value between -10px and 10px
      transform: translate((random(20) - 10) * 1px, (random(20) - 10) * 1px);

.twitter-x__logo {
  // other styles

  @include isMorphing {
    animation: shaking var(--twitter-shaking-at) var(--twitter-shaking-delay);

Logo morphing and colors change

So after previous steps are done (including changing bird fill color to transparent), it's time for the main show of this demo.

First let's quickly cover black background expansion. It's done via technique where you are placing large circle in the middle that covers the entire container and scaling it to 0 by default, so it's not visible in the initial state. And once it's a showtime, you are just quickly scaling it to 1, which "expands" it from the center and makes it look wayyyyy better than just boring background-color transition of the main container. And on top of it we can also cover some content with it (assuming proper elements order or z-indexes assigned to them), like Elon's image, without needing to add second class or any other annoying stuff.

.twitter-x__black-bg {
  position: absolute;
  left: 50%;
  top: 50%;
  // 150vmax ensures that this element will cover the entire screen no matter what
  // (assuming that parent container doesn't have it's own overflow: hidden)
  width: 150vmax;
  height: 150vmax;
  margin-left: -75vmax;
  margin-top: -75vmax;
  border-radius: 50%;
  background: #000;
  transform: scale(0);
  will-change: transform;

  @include isMorphing {
    transition: transform var(--logo-morphing-at) var(--logo-morphing-delay);
    transform: scale(1);

As for the logo morphing, that's where we'll need some javascript. I won't be able to cover the whole topic of svg morphing, because fairly speaking I am a little bit too dumb for it, but tldr is that you can use libraries that are doing "best-estimate interpolations" for figuring out how one svg path shape can morph into another, and then providing you with values from 0 to 1 relative to the progress of the animation (and most of the time they are handling animation themselves).

In the perfect world I would be using something like GSAP MorphSVGPlugin, but unfortunately it requires paid membership, which is a no go for my demos. After doing a little bit of research with available open-sourced libraries, I settled on flubber which got good amount of weekly downloads, nice api and reasonable size.

Hopefully comments in code below are enough to explain what is going on:

// this useEffect runs once at the start of component's initialization (which is also being triggered by key prop change)
useEffect(() => {

  const colorChangeAnim = animationsWithDelaysMap['logo-morphing'] * 1000;
  const colorChangeDelay =
    animationsWithDelaysMap['logo-morphing-delay'] * 1000;

  // using good old dom selector, nothing fancy
  // but in a more serious project I would use useRef hook to get a reference to this element to evade relying on global classes
  const $path = document.querySelector('.twitter-x__logo-svg path');
  const twitterPath = $path?.getAttribute('d') || '';

  // I'm using flubber library ( to morph twitter svg into X rectangle
  // GSAP MorphSVGPlugin is most likely is a better choice, but it requires paid membership to use it
  const interpolator = interpolate(twitterPath, targetPath);

  // I'm creating startTime variable here and not in timeout because of annoying js closure behavior
  const startTime =;

  let linejoinChanged = false;

  setTimeout(() => {
    // check mdn for api reference
    // but overall tldr is that rAF runs callback function on next frame, which is usually 60 times per second

    function draw() {
      // since startTime is defined outside of this function, we need to subtract the delay also to get proper elapsed time
      const elapsed = - startTime - colorChangeDelay;
      const p = elapsed / colorChangeAnim; // progress of animation, from 0 to 1
      const d = interpolator(p);

      $path?.setAttribute('d', d);

      if (p < 1) {
        // run this function in rAF loop until animation is finished

      if (p >= 0.5 && !linejoinChanged) {
        // twitter icon got round linejoin by default to make it look smoother,
        // but X rectangle requires sharp corners, so this part changes it mid-animation
        linejoinChanged = true;
        $path?.setAttribute('stroke-linejoin', 'miter');
  }, colorChangeDelay);
}, []); // empty array dependency means that this effect will run only once

And the last part of this animation step is changing stroke color from twitter-blue to white, which is not worth the code-embed.

Second part of X logo

Once morphing is done, we need to finish X logo by animating appearance of second line (bottom-left to top-right). But in our case it's actually 2 lines, both of which are painted somewhere from the center to their respective corners. It's done this way because I need to keep background inside of first X rectangle transparent, to see the black background behind (and I definitely don't want to manually change fill of that svg). So for this reason we can't allow that line going through the middle of the X.

As for the animation itself we are relying on scaling the lines from 0 to 1 from transform-origin located in a middle. More info in code comments below:

.twitter-x__logo-svg2 {
  overflow: visible;
  position: absolute;
  inset: 0;
  fill: #fff;

  path {
    transform: scale(0);

    // setting custom transform-origin is required to make the animation look like the line is being drawn from the center
    // ideally we would be using % values, but svg got this ancient trouble where transform-origin with % just doesn't works in many browsers
    // libraries like GSAP got their own logic to allow % values, which relies on some internal calculations, but we don't have such luxury here
    &:first-child {
      // keep in mind that this svg got viewBox="0 0 270 270", so px values are relative to these dimensions, unlike with twitter icon which is 24x24
      transform-origin: 100px 160px;

    &:last-child {
      transform-origin: 160px 100px;

    @include isMorphing {
      // cubic-bezier transition-timing-function allows you to create fancier animations, where elements could be bouncing or looking slightly elastic
      // you can check this playground to get the better idea
      transition: transform var(--x-part-2-at) var(--x-part-2-delay) cubic-bezier(0.13, 0.9, 0.3, 1.3);
      transform: scale(1);

Once line animation is done, we only have left doge and reset appearances, which are done the same way as elon.

How reset works

// we are using this wrapper to reset our component state and rerun useEffect by changing the key prop
export default function ResetWrapper() {
  const [refreshMs, setRefreshMs] = useState(0);

  return (
      onReset={() => setRefreshMs(} // using timestamp is probably the most braindead and bulletproof way to get new unique key each time

Additional notes:

  • Unfortunately morphing animation is kinda scuffed at the beginning, it just instantly jumps from bird shape to something very weird, which is the reason why logo-morphing animation step is only 0.2s long. Making shitty parts of animations very fast is the easiest crutch you can use, hoping that majority of people won't notice the poor quality.
  • One of the reasons for making this demo was proving to myself that I'm not washed :D I woke up on Monday (with SG time, which is +12 to US), saw all the memes on twitter about new logo and knew that I had to move fast to capitalize on this hot topic. I finalized my idea during brunch, and few hours after returning home the demo was done and published. This article took me way longer to write than the demo, which is normal I guess (writing is fucking hard, jesus christ).

Please follow me on twitter for my latest demos, tutorials and cooked takes.