After studying Louis Lazaris’ insightful article “Those HTML Attributes You Never Use”, I’ve requested myself (and the community) which properties and selectors are lesser-known or must be used extra usually. Some solutions from the neighborhood shocked me, as they’ve included some very helpful and often-requested CSS options which had been made obtainable previously 12 months or two.

The next checklist is created with neighborhood requests and my private picks. So, let’s get began!

all Property

This can be a shorthand property which is commonly used for resetting all properties to their respective preliminary worth by successfully stopping inheritance, or to implement inheritance for all properties.

  • preliminary
    Units all properties to their respective preliminary values.
  • inherit
    Units all properties to their inherited values.
  • unset
    Modifications all values to their respective default worth which is both inherit or preliminary.
  • revert
    Ensuing values rely on the stylesheet origin the place this property is positioned.
  • revert-layer
    Ensuing values will match a earlier cascade layer or the following matching rule.

aspect-ratio for Sizing Management

When aspect-ratio was initially launched, I assumed I gained’t use it outdoors picture and video parts and in very slim use-cases. I used to be shocked to seek out myself utilizing it in an analogous manner I’d use currentColor — to keep away from unnecessarily setting a number of properties with the identical worth.

With aspect-ratio, we are able to simply control size of a component. For instance, equal width and top buttons may have a side ratio of 1. That manner, we are able to simply create buttons that adapt to their content material and ranging icon sizes, whereas sustaining the required form.

I assumed that this problem can’t be mounted, and I moved on. One of many tweets from the neighborhood ballot advised that I ought to look into font-variant-numeric: tabular-nums, and I used to be shocked to discover a plethora of choices that have an effect on font rendering.

For instance, tabular-nums mounted the aforementioned problem by setting the equal width for all numeric characters.

Render Efficiency Optimization

In the case of rendering efficiency, it’s very uncommon to run into these points when engaged on common initiatives. Nevertheless, within the case of huge DOM bushes with a number of hundreds of parts or different related edge instances, we are able to run into some efficiency points associated to CSS and rendering. Fortunately, we’ve got a direct manner of coping with these efficiency points that trigger lag, unresponsiveness to consumer inputs, low FPS, and so on.

That is the place comprise property is available in. It tells the browser what gained’t change within the render cycle, so the browser can safely skip it. This will have penalties on the format and magnificence, so ensure to check if this property doesn’t introduce any visible bugs.

.container {
  /* baby parts will not show outdoors of this container so solely the contents of this container must be rendered*/
  comprise: paint;
{

This property is kind of complicated, and Rachel Andrew has covered it in nice element in her article. This property is considerably tough to reveal, as it’s most helpful in these very particular edge instances. For instance, Johan Isaksson lined a kind of examples in his article, the place he seen a serious scroll lag on Google Search Console. It was attributable to having over 38 000 parts on a web page and was mounted by containing property!

As you’ll be able to see, comprise depends on the developer understanding precisely which properties gained’t change and understanding learn how to keep away from potential regressions. So, it’s a bit tough to make use of this property safely.

Nevertheless, there’s an choice the place we are able to sign the browser to use the required comprise worth mechanically. We are able to use the content-visibility property. With this property, we are able to defer the rendering of off-screen and below-the-fold content material. Some even check with this as “lazy-rendering”.

Una Kravets and Vladimir Levin lined this property of their travel blog example. They apply the next class identify to the below-the-fold weblog sections.

.story {
  content-visibility: auto; /* Behaves like overflow: hidden; */
  contain-intrinsic-size: 100px 1000px;
}

With contain-intrinsic-size, we are able to estimate the scale of the part that’s going to be rendered. With out this property, the scale of the content material could be 0, and web page dimensions would preserve rising, as content material is loaded.

Going again to Una Kravets and Vladimir Levin’s journey weblog instance. Discover how the scrollbar jumps round, as you scroll or drag it. That is due to the distinction between the placeholder (estimated) measurement set with contain-intrinsic-size and the precise render measurement. If we omit this property, the scroll jumps could be much more jarring.

See the Pen Content-visibility Demo: Base (With Content Visibility) by Vladimir Levin.

Thijs Terluin covers several ways of calculating this worth together with PHP and JavaScript. Server-side calculation utilizing PHP is particularly spectacular, as it could automate the worth estimation on bigger set of varied pages and make it extra correct for a subset of display screen sizes.

Needless to say these properties must be used to repair points as soon as they occur, so it’s secure to omit them till you encounter render efficiency points.

Conclusion

CSS evolves consistently, with extra options being added every year. It’s vital to maintain up with the newest options and greatest practices, but in addition preserve an eye fixed out on browser help and use progressive enhancement.

I’m positive there are extra CSS properties and selectors that aren’t included right here. Be at liberty to tell us within the feedback which properties or selectors are much less recognized or must be used extra usually, however could also be a bit convoluted or there’s not sufficient buzz round them.

Additional Studying on Smashing Journal