[canvas=container] what is this?

Question

css

[canvas=container] {
width: 100%;
height: 100%;
overflow-y: auto;
position: relative;
background color: white /* Basic background color, overwrite this in your own css. */
-webkit-overflow-scrolling: touch; /* Enables momentum scrolling on iOS devices, may be removed by setting to 'auto' in your own CSS. */
}
[canvas=container] what is this? And where can I read what it is used for?

Answer 1

Creates an area where you can use JavaScript to draw different objects, display images, transform them, and change properties. Using the tag, you can create drawings, animation, games, etc.
Source

Answer 2

search magic

Answer 3

if you're talking about css, then this is a call to date attributes.
for example you have a div:
then you can refer to it in css:

[data-count="1"] {

}