Bootstrap 4 CSS causing Chrome's print “Layout” to disappear

问题

I want my website users to be able to print pages in either portrait or landscape mode.

When printing from Google Chrome using Bootstrap 3.3.7, the Chrome print settings has a Layout option. Simply changing the css/js to 4.0.0, the Chrome print settings no longer has the Layout option. I suspect this has something to do with one of these CSS directives:

@page
@media

回答1:

I was able to fix this by adding this CSS:

@page {
    size: auto;
}

来源：https://stackoverflow.com/questions/49018636/bootstrap-4-css-causing-chromes-print-layout-to-disappear