Cascading Style Sheetsis a computer language used to represent file styles such as HTML (an application of the standard universal language) or XML (a subset of the standard Universal Markup Language). CSS is currently the latest version of CSS3, is to be able to truly achieve Web page performance and content separation of a style design language. Compared to the performance of traditional HTML, CSS can control the placement of objects in the Web page with pixel-level precision, support almost all font size styles, have the ability to edit Web objects and model styles, and be able to conduct preliminary interaction design, is currently based on the best performance design language text display. CSS can be based on the understanding of different users to simplify or optimize the writing, for all types of people, have a strong legibility.
Development History
CSS1As a recommendation, CSS1 was released on December 17, 1996. This recommendation was re-revised on January 11, 1999.
CSS2As a recommendation, CSS2 was released on January 11, 1999. CSS2 adds support for media (printers and auditory devices) and downloadable fonts.
CSS3CSS3 plans to divide the CSS into smaller modules. There are three ways to use style sheets on a site page:
- An linking (also called an external style): Links a Web page to an external style sheet.
- Inline embedding (also called Inner page style): Creates an embedded style sheet on a Web page.
- Inline inline (also called inline style): Applies an inline style to individual page elements.
Among them, priority: inline > Embedded > External style sheet external style sheets are ideal when styles need to be applied to many pages. With an external style sheet, you can change the appearance of the entire site by changing a file.
Internal style sheetAn internal style sheet can be used when a particular style is required for a single file. You can define an internal style sheet in the head section through the <style> tag. Inline styles you can use inline styles when special styles need to be applied to individual elements. The way to use inline styles is to use style attributes in related tags. Style properties can contain any CSS properties.
Layout FeaturesFor spiders crawling a site page, if there are too many garbage code, will make the search spider to its unfriendly, distrust, while the spider crawl speed will therefore slow down, for the website SEO, is a big taboo. As with the traditional table page, we need to optimize the site, which requires the use of css+div; I. Streamline the code and reduce the difficulty of refactoring. Two. Web Access speed three. SEO optimization four. browser compatibility five. Css+div Web page layout often made a small mistake
CSS (cascading style sheets)
