Usage tip sharing: guide you to write CSS code easily

CSS (Cascading Style Sheets) is a language used for web design. It is an important part of HTML (Hypertext Markup Language). Using CSS, you can make your web pages more attractive, have better readability, greater accessibility, and better browser compatibility. In this article, we’ll explain how to create CSS and provide some practical tips to help you write CSS code more easily.

1. Create a new CSS file

Before creating the CSS, please confirm that you have created the HTML file and added the code snippet that references the CSS. Add the following code snippet to the HTML file:

Hello World!

Here, we add a link tag in the head tag, which will reference the CSS file named "style.css". Please make sure to create a file called "style.css" in the same directory as your HTML file.

2. Add CSS rules

You can add CSS rules in a variety of ways, such as:

• Write an external CSS file (as mentioned above) .
• Use the style tag at the head of the HTML file to define the internal CSS style sheet.
• Use inline style attributes directly on HTML elements.

No matter which method you use, please make sure you have learned CSS syntax before writing CSS code. Here is a simple example:

h1 {
color: red;
font-size: 28px;
}

Here, we have written an HTML CSS rules for h1 tags. It specifies the text color to be red and sets the font size to 28 pixels.

3. Using CSS Selectors

CSS selectors are a method used to identify HTML elements that require CSS styling. The following are several important CSS selectors:

• Tag selectors: such as h1, p, div, etc.
• Class selector: such as .menu, .sidebar, etc.
• ID selector: such as #header, #footer, etc.
• Attribute selector: such as [type="text"], [href$=".pdf"], etc.

When writing CSS code, choose the appropriate selector according to your needs.

4. Combined Selector

When writing CSS code, you usually need to use a combined selector to set specific elements. The following are some common combination selectors:

• Descendant selectors (separated by spaces): such as div p selects all p elements within the div.
• Child element selector (separated by >): For example, #menu > li selects all li elements belonging to #menu.
• Adjacent sibling element selector (separated by ): For example, h1 p selects the adjacent (p) elements after the h1 element.
• Universal descendant selector (separated by ~): For example, p ~ span selects all adjacent span elements after p.

5. Using the CSS box model

Every HTML element has its corresponding box model. It consists of content area, padding area, border area and margin area. When writing CSS code, use the box model property to set the width of the element:

• width sets the width of the element.
• height sets the height of the element.
• padding sets the padding of the element.
• border Set the border of the element.
• margin Set the margin of the element.

6. Debugging CSS code

When writing CSS code, you may encounter various problems. In this case, debugging the CSS code is very important. Here are some practical debugging tips:

• Add comments in CSS rules to make it easier to understand and debug your code.
• Use your browser's development tools (such as Chrome DevTools or Firebug) to view the style and layout of elements.
• Remove or comment out parts of the code to gradually narrow down the scope of the problem and find the part that is causing the problem.

7. Summary

In this article, we discussed how to create CSS, including creating new CSS files, adding CSS rules, and using CSS selectors and combining selectors, using the CSS box model, and debugging CSS code. Hopefully these tips will help you write better CSS code and create more engaging web pages.

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