Faced with the fact that the html tag in the class attribute lists a set of values.
What is it used for?

Here is an example:

 <html lang="ru" class="js flexbox flexboxlegacy canvas canvastext webgl no-touch geolocation postmessage websqldatabase indexeddb hashchange history draganddrop websockets rgba hsla multiplebgs backgroundsize borderimage borderradius boxshadow textshadow opacity cssanimations csscolumns cssgradients cssreflections csstransforms csstransforms3d csstransitions fontface generatedcontent video audio localstorage sessionstorage webworkers applicationcache svg inlinesvg smil svgclippaths no-ipad no-iphone no-ipod no- appleios positionfixed">
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    because C from CSS is Cascading, which means these properties can be applied to nested elements - Grundy
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    @ Mr. Music What does "class attribute with properties" mean? Can you give an example? - Vlad from Moscow
  • one
    And why the question zaminusovan? Explain experts. - mJeevas
  • Any intelligible answer would be? - mJeevas 4:52 pm
  • @ Mr. Music And where are the properties here? - Vlad from Moscow

2 answers 2

This is used to be able to use cascading CSS styles to support certain features. Look closely at the class names and they will tell you a lot. For example, class flexbox suggests that this page supports flexbox properties, etc.

    This is similar to the list of client features defined by the modernizr script (see http://habrahabr.ru/post/144352/ ). When connected, the script defines the properties of the browser and modifies the corresponding classes of the html tag. In css using these classes, you can define different styles depending on the capabilities of the browser.