Using web standards to design websites, the transition method mainly uses XHTML+CSS, and css style sheets are essential. This requires all web designers to be proficient in CSS. If you have not used it before, start learning now. To create a website that complies with web standards, you cannot design beautiful pages without knowing CSS.
In fact, all aspects of performance need to be implemented with CSS. We used to use tables for positioning and layout, but now we have to use DIV for positioning and layout. This is a change in the way of thinking, which is a bit uncomfortable at first. Haha, there will be resistance to any change. In order to enjoy the "benefits" brought by standards, it is worthwhile to give up some old traditional practices.
In the design that complies with web standards, we use the external calling method. The benefits are self-evident. You can change the style of the page without modifying the page and only modify the .css file. If all pages call the same style sheet file, then changing one style sheet file can change the styles of all files.
Looking at the original code of some standards-compliant sites, you may see the following two sentences where the style sheet is called:
Why write it twice?
In fact, under normal circumstances, it is enough to use the external link method (that is, the first sentence). The double table call I use here is just an example. The "@import" command is used to enter the style sheet. The "@import" command is invalid in Netscape 4.0 browsers. In other words, when you want certain effects to be hidden in the Netscape 4.0 browser and displayed in 4.0 or above or other browsers, you can use the "@import" command method to call the style sheet.