CSS：HTML和正文标签的宽度设置为100％-为什么需要这样做？

Question

I'm curious what is the purpose of html, body{width:100%} in the css file? Is it kind of css reset code?

Disabling this piece of code doesn't affect on what I see in the browser. Is it a "bugfix" for some old browser or for mobile devices? Am I missing something? Could anybody please explain?

Thank you.

Answer 1

As far as I know, width:100% is used when you want a block-level element to fill any remaining space inside it's parent or when an element is inheriting a set width value that you want to override. But in most cases it is unnecessary or will bring undesirable results.

Answer 2

As far I know it's not necessary maximum time, some time not mentioning this is creates problem with IE browser by improper formatting of the content. otherwise there is no need.

Answer 3

Understand it this way.

HTML is parent of BODY.
BODY is parent of the content.
Body looks to its parent (HTML) for how to scale the dynamic property, so the HTML element needs to have it's height set.And since the content of body will probably need to change dynamically. Setting min-height of the body to 100% makes that happen.

If we are using overflow:hidden with body and the body isn't able to take the height of dynamic content then the part outside the body height won't be visible .

Now the question is
When doesn't the body take the height of the dynamic content ?

When we are using floating elements .The height of the floating elements are not calculated by the parent until we use overflow:auto .