At the end of the day, the bulk of CSS is made up not of sexy, fancy features like Grid or animations; but of small, often niche properties that may at first seem useless, but then end up one day saving you dozens of hours of work.
CSS variables and support queries fit in that category: they'll take a little while to grow on you, but once you grasp their full potential you'll wonder how you ever managed without them.
The size of the outer circle corresponds to the total number of users who know about a feature, while the inner one represents those who have actually used it.
Hover on each node to view detailed data along with an overlay representing the total number of survey respondents.
Usage by Years Of Experience
The “overall” column shows overall usage for each feature (respondents who selected “have used it”), while the following columns show the usage ratio for each “years of experience” bracket.
A brighter pink background indicates a higher-than-overall-average ratio for a given bracket.
@supports CSS at-rule lets you specify declarations that depend on a browser's support for one or more specific CSS features. This is called a feature query. The rule may be placed at the top level of your code or nested inside any other conditional group at-rule.
contain CSS property allows an author to indicate that an element and its contents are, as much as possible, independent of the rest of the document tree. This allows the browser to recalculate layout, style, paint, size, or any combination of them for a limited area of the DOM and not the entire page, leading to obvious performance benefits.
calc() CSS function lets you perform calculations when specifying CSS property values. It can be used anywhere a
<integer> is allowed.