First, we set up a website to know his layout, a web page is a big div, divided into many small parts, if not all of the elements set float, then he is vertical, if coupled with a floating ( float ) is horizontal, if set floating, then we have to write a clear element float clear: both, if not set, will overlap with the following content! Float can be set in html, but not recommended, it recommended setting clear float in CSS;
1display: specifies the type of element to be generated box
display: block; block-level element is displayed
display: inline; inline element display
display: inline-block; inline block elements
display: flex; elastic box
In a site that we can insert audio with the relative position of the video, as well as fixed window with absolute position
position: static; fixed (absolute positioning, relative to the browser window, meaning that no matter how you drop down, he is in the original position); relative; relative positioning, relative to the normal position absolute; (absolute positioning, there is a scroll bar case, fixed positioning is not moved with the scroll bar, and with the scroll bar will absolute)