Three methods for importing css styles into webpages

Three methods for importing css styles into webpages,
If you are careful, you will find that many major portal sites directly write css in the document. There are also many sites with link links and some sites with import such as taobao. so what are their advantages and disadvantages? Let's take a look.
I. Directly writing css on the page and loading the page at the same time can reduce the connection thread on the server. This is why large websites are directly written in the document, because traffic is large, you need to consider it everywhere.
2. link is imported to the outside, so the link style is loaded only after the page content is loaded. This makes loading interrupted when the network speed is slow, the page is messy. I think you should have read it,
3. What is the role of import? In fact, the difference between it and link is that import must wait until all pages are loaded before loading the css document, in addition, link can connect to various types of document link labels. In addition to loading CSS, link can also do many other things, such as defining RSS and rel connection attributes, @ import: Only CSS can be loaded.

Well, I understand this much. For the original site reprinted, please note: www.111cn.net/cssdiv/css.html