HTML and CSS are one of the two most important components of web development. HTML is responsible for defining the structure and content of web pages, while CSS is responsible for defining the style and presentation of web pages. There are three ways to write CSS: inline styles, internal styles, and external style sheets.
1. Inline style
Inline style is a CSS style that is directly applied to HTML elements. When using inline styles, the CSS style will be written in the style attribute of the HTML element. For example:
<p>这是一段红色的文字</p>
The color:red in the style attribute means setting the text color to red.
Inline styles do not require special CSS files, and styles can be quickly added and modified in individual HTML elements. However, it can make HTML files difficult to read and maintain because styles and text are mixed together. In addition, if you need to change a set of inline styles, you need to manually modify each element, which is quite troublesome.
2. Internal styles
Internal styles use the style tag to embed CSS styles into HTML documents. Embed the style tag in the head area of the HTML document, and then write the CSS style in the tag, as shown below:
标题 <p>这是一段红色的文字</p>
The above code sets the text color to red. Internal styles separate HTML documents from CSS styles, making style maintenance more convenient. However, if you need to add a lot of styles to the same HTML document, using internal styles will increase the file size and make the file download time longer.
3. External style sheet
The external style sheet uses the link tag to link the HTML document with the external CSS style sheet. External style sheets usually contain all styles and can be reused in multiple HTML documents. As shown below:
Introduce an external style sheet into the html file:
标题 <p>这是一段红色的文字</p>
Define the CSS style in the style.css file:
p { color: red; }
Using an external style sheet allows complete separation HTML and CSS codes make it easier to maintain and modify styles. In addition, because it can be reused in multiple HTML files, it can reduce file size and increase page loading speed. Therefore, external style sheets are the recommended way to write CSS.
Summary
The above are three ways to write CSS in HTML: inline styles, internal styles and external style sheets. Inline styles and internal style methods are suitable for situations where styles need to be written and modified quickly, while external style sheets are suitable for situations where multiple HTML files contain the same style. Depending on the situation, you can choose a CSS writing method that suits you to implement the style design of the web page.
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