Css-div Height 100% Setup Issues

div commonly used properties width and height, sometimes if we need to make div height is the height of the entire screen, set height:100% found does not have any effect, it is not set the wrong, but in the World wide specification about the percentage of the setting is relative to the parent element, as follows:

<! DOCTYPE html>
Find that the height of the div is only the height of the text, if you need to let the div fill the entire screen, we need to set the height of the parent element, that is, HTML and body:
    html,body {        height:100%;        padding:0;        margin:0;    }
The height is relative to the parent element, but the default width of the HTML-level element is 100%, which is the entire line ~
Css-div Height 100% Setup Issues