Pop up the simplest js code for modal mask layer_javascript skills

Suppose we have a container container as follows:

Copy code The code is as follows:

Now we need to pop up a div layer in the web page so that the container cannot be operated before closing the pop-up div layer.
Then, we first need to define the div layer of this mask as follows:

Copy the code The code is as follows:

The next step is to use js to make the mask layer always display on the screen and the content under the mask layer cannot be manipulated. Click the close button to close the mask layer

Copy code The code is as follows: