CSS Smooth Scroll

Improving the user experience of web applications has always been a priority of mine. I always come back to the same though I've had for 20 years: "users expect a web app to work -- let's make the app a joy to use." Over the years we've employed JavaScript to improve the UX, but over time those strategies either become clunky or get baked into the web languages themselves. One such feature is smooth scrolling; a great UX improvement but annoying if imperfect. Did you know that you can implement smooth scrolling with just CSS?

The scroll-behavior CSS property controls the scrolling strategy for overflow elements with scrolling behavior, and only when triggered by navigation or CSSOM properties. The default scroll-behavior value is auto, which represents no visual effect -- immediately scrolling to the target element with no animation. To provide users a smooth scrolling experience, you can use the smooth value:

/* slide between items */
.slideshow ul {
  scroll-behavior: smooth;
}

Of course you do lose some visual control when you use a native browser API -- most notably animation speed and animation curve. On the positive side you don't need to add kilobytes of JavaScript that you need to maintain to achieve a very similar effect!