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What are the different ways to include CSS in an HTML document, and what are their pros and cons?
What are the different ways to include CSS in an HTML document, and what are their pros and cons?
Jun 20, 2025 am 12:38 AM
There are three common ways to introduce CSS into HTML documents, namely inline styles, internal style sheets and external style sheets. 1. Inline styles are written directly in the style attribute of the HTML tag, which is suitable for temporary modification of individual element styles. The advantage is that they are simple and direct, and the disadvantage is that they are poor maintainability and are not conducive to separating concerns; 2. The internal style sheet is written in
through the <style> tag, and the style is centrally managed. It is suitable for single pages or small websites, but is not convenient for multi-page sharing styles; 3. The external style sheet writes CSS to an independent file and introduces it through <link>, which supports multi-page sharing styles, which are easy to maintain and perform performance optimization, and is suitable for medium and large projects. It is the most commonly used method in modern web development. Overall, the larger the project size, the more external style sheets should be used, while inline and internal styles are suitable for debugging or small-scale applications.There are three common ways to introduce CSS into HTML documents: inline styles, internal style sheets, and external style sheets. They each have their own applicable scenarios and have their own advantages and disadvantages.
Inline Styles
This is the most straightforward way to write styles in the style attribute of the HTML tag. For example:<pre class='brush:php;toolbar:false;'> <p style="color: red; font-size: 16px;">This is a red text</p></pre><p> <strong>advantage:</strong></p><ul><li> Simple and direct, suitable for temporary modification of individual element styles.</li><li> No additional files or tags are required and effective quickly.</li></ul><p> <strong>shortcoming:</strong></p><ul><li> Poor maintainability, the style and structure are mixed together, which is not conducive to later maintenance.</li><li> The style cannot be reused, and there are many repetitions of code.</li><li> It is not conducive to separating the focus and violates the best practices of web development.</li></ul><p> This method is more suitable for testing or very small projects, or when an element style must be unique.</p><hr /><h3> Internal Style Sheet</h3><p> Write CSS directly into <code><head> part of the HTML file through the <style> tag:
<head>
<style>
p {
color: blue;
}
</style>
</head>advantage:
- Centralized style management is easier to maintain than inline.
- No external files are required, suitable for single page applications or simple pages.
shortcoming:
- Styles cannot be shared between multiple pages, resulting in duplicate work.
- If there are many pages, the style code will bloat, affecting maintainability.
This approach is suitable for style definitions for small websites or individual pages, but is not recommended for large projects.
External Style Sheet
Write CSS in a separate .css file and import it into HTML via the <link> tag:
<link rel="stylesheet" href="styles.css">
advantage: shortcoming: This is the most commonly used method in modern web development, especially suitable for medium and large projects or multi-page websites. In general, which method to choose depends on the size and requirements of the project. For most actual projects, using an external stylesheet is the best choice. If it is a temporary debugging or small page, you can consider inline or internal styles. Basically, this is all, understanding different applicable scenarios can allow you to organize web page styles more flexibly. The above is the detailed content of What are the different ways to include CSS in an HTML document, and what are their pros and cons?. For more information, please follow other related articles on the PHP Chinese website!
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