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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

              
                <main style="--length: 6;">
  <header>
    <h1>Famous Elephants</h1>
    <button class="Button js-toggle-button">
      <span class="Button__show-text js-show-text is-shown">Show</span>
      <span class="Button__hide-text js-hide-text" hidden>Hide</span>
    </button>
  </header>
  <nav>
    <ul class="Menu js-menu">
      <li class="Menu__item">
        <a href="#" class="Menu__link js-link" style="--index: 0;">Babar</a>
      </li>
      <li class="Menu__item">
        <a href="#" class="Menu__link js-link" style="--index: 1;">Dumbo</a>
      </li>
      <li class="Menu__item">
        <a href="#" class="Menu__link js-link" style="--index: 2;">Echo</a>
      </li>
      <li class="Menu__item">
        <a href="#" class="Menu__link js-link" style="--index: 3;">Jumbo</a>
      </li>
      <li class="Menu__item">
        <a href="#" class="Menu__link js-link" style="--index: 4;">Packy</a>
      </li>
      <li class="Menu__item">
        <a href="#" class="Menu__link js-link" style="--index: 5;">Ruby</a>
      </li>
    </ul>
  </nav>
  
  <p>
    Click the button above to see a list of famous elephants.
  </p>
</main>
              
            
!

CSS

              
                .Menu {
  list-style: none;
  margin: 0;
  padding: 0;
  position: absolute;
  width: 100%;
  z-index: 1;
}

.Menu__link {
  --index: 0;
  
  align-items: center;
  background: #dde;
  border-top: 1px solid #aac;
  color: #002;
  display: flex;
  font-size: 1.25em;
  justify-content: space-between;
  line-height: 1;
  opacity: 0;
  padding: 1em;
  text-decoration: none;
  transform: translateX(100%);
  transition-delay: calc(0.025s * (var(--length) - (var(--index) + 1)));
  transition-duration: 0.2s;
  transition-timing-function: ease-out;
  transition-property: opacity, transform;
}

.Menu__link::after {
  align-items: center;
  border-right: 1px solid #002; 
  border-top: 1px solid #002;
  content: "";
  display: flex;
  height: 0.25em;
  font-size: 2em;
  justify-content: center;
  margin-right: 0.25em;
  transform: rotate(45deg);
  width: 0.25em;
}

.Menu.is-open .Menu__link {
  opacity: 1;
  transform: translateX(0);
  transition-delay: calc(0.025s * var(--index));
}

/**
 * Unrelated CSS
 *
 * The following CSS is used to lay out aspects of the demo 
 * unrelated to our staggered animations.
 */

body {
  background: #334;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";}

main {
  background: #eef;
  color: #002;
  height: 27em;
  margin: 0 auto;
  max-width: 20em;
  overflow: hidden;
  position: relative;
}

header {
  align-items: center;
  background: #dde;
  display: flex;
  justify-content: space-between;
  padding: 1em;
  position: relative;
  z-index: 2;
}

h1 {
  font-size: 1.25em;
  margin: 0;
}

.Button {
  background: #33c;
  border: none;
  border-radius: 10em;
  color: #fff;
  cursor: pointer;
  font-size: 1em;
  height: 2em;
  position: relative;
  transition: background ease-out 0.3s;
  text-align: center;
  width: 5em;
}

.Button__hide-text,
.Button__show-text {
  left: 0;
  opacity: 0;
  position: absolute;
  right: 0;
  top: 0.35em;
  text-align: center;
  transition: opacity ease-out 0.3s;
}

.Button__hide-text.is-shown,
.Button__show-text.is-shown {
  opacity: 1;
}

p {
  line-height: 1.4;
  padding: 0 1em;
}
              
            
!

JS

              
                const button = document.querySelector('.js-toggle-button');
const menu = document.querySelector('.js-menu');
const links = document.querySelectorAll('.js-link');

const showTextTransitioner = transitionHiddenElement({
  element: document.querySelector('.js-show-text'),
  visibleClass: 'is-shown',
});

const hideTextTransitioner = transitionHiddenElement({
  element: document.querySelector('.js-hide-text'),
  visibleClass: 'is-shown',
})

const transitionDelay = 0.025;
const transitionLength = 0.2;
const itemLength = 6;
const staggeredTransitionLength = (transitionDelay * (itemLength - 1)) + transitionLength;

const menuTransitioner = transitionHiddenElement({
  element: document.querySelector('.js-menu'),
  visibleClass: 'is-open',
  waitMode: 'timeout',
  timeoutDuration: staggeredTransitionLength * 1000
})

button.addEventListener('click', () => {
  toggleMenu();
});

links.forEach(link => {
  link.addEventListener('click', e => {
    e.preventDefault();
    toggleMenu();
  });
});

const toggleMenu = () => {
  showTextTransitioner.toggle();
  hideTextTransitioner.toggle();
  menuTransitioner.toggle();
}

/** 
 * Library code
 * Using https://www.npmjs.com/package/@cloudfour/transition-hidden-element
 */

function transitionHiddenElement({
  element,
  visibleClass,
  waitMode = 'transitionend',
  timeoutDuration,
  hideMode = 'hidden',
  displayValue = 'block'
}) {
  if (waitMode === 'timeout' && typeof timeoutDuration !== 'number') {
    console.error(`
      When calling transitionHiddenElement with waitMode set to timeout,
      you must pass in a number for timeoutDuration.
    `);

    return;
  }

  // Don't wait for exit transitions if a user prefers reduced motion.
  // Ideally transitions will be disabled in CSS, which means we should not wait
  // before adding `hidden`.
  if (window.matchMedia('(prefers-reduced-motion: reduce)').matches) {
    waitMode = 'immediate';
  }

  /**
   * An event listener to add `hidden` after our animations complete.
   * This listener will remove itself after completing.
   */
  const listener = e => {
    // Confirm `transitionend` was called on  our `element` and didn't bubble
    // up from a child element.
    if (e.target === element) {
      applyHiddenAttributes();

      element.removeEventListener('transitionend', listener);
    }
  };

  const applyHiddenAttributes = () => {
    if(hideMode === 'display') {
      element.style.display = 'none';
    } else {
      element.setAttribute('hidden', true);
    }
  }

  const removeHiddenAttributes = () => {
    if(hideMode === 'display') {
      element.style.display = displayValue;
    } else {
      element.removeAttribute('hidden');
    }
  }

  return {
    /**
     * Show the element
     */
    show() {
      /**
       * This listener shouldn't be here but if someone spams the toggle
       * over and over really fast it can incorrectly stick around.
       * We remove it just to be safe.
       */
      element.removeEventListener('transitionend', listener);

      /**
       * Similarly, we'll clear the timeout in case it's still hanging around.
       */
      if (this.timeout) {
        clearTimeout(this.timeout);
      }

      removeHiddenAttributes();

      /**
       * Force a browser re-paint so the browser will realize the
       * element is no longer `hidden` and allow transitions.
       */
      const reflow = element.offsetHeight;

      element.classList.add(visibleClass);
    },

    /**
     * Hide the element
     */
    hide() {
      if (waitMode === 'transitionend') {
        element.addEventListener('transitionend', listener);
      } else if (waitMode === 'timeout') {
        this.timeout = setTimeout(() => {
          applyHiddenAttributes();
        }, timeoutDuration);
      } else {
        applyHiddenAttributes();
      }

      // Add this class to trigger our animation
      element.classList.remove(visibleClass);
    },

    /**
     * Toggle the element's visibility
     */
    toggle() {
      if (this.isHidden()) {
        this.show();
      } else {
        this.hide();
      }
    },

    /**
     * Tell whether the element is hidden or not.
     */
    isHidden() {
      /**
       * The hidden attribute does not require a value. Since an empty string is
       * falsy, but shows the presence of an attribute we compare to `null`
       */
      const hasHiddenAttribute = element.getAttribute('hidden') !== null;

      const isDisplayNone = element.style.display === 'none';

      const hasVisibleClass = [...element.classList].includes(visibleClass);

      return hasHiddenAttribute || isDisplayNone || !hasVisibleClass;
    },

    // A placeholder for our `timeout`
    timeout: null
  };
}
              
            
!
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