Detailed introduction to the difference between . and > in css
CSS is an essential part of front-end development. It can be used to control the style and layout of web pages. In CSS, . and > are very commonly used symbols, but they have different functions and usage scenarios. This article will introduce in detail the difference and usage of the two symbols.
1. The role and usage scenarios of .
. is a basic symbol in CSS. Its function is to select HTML elements with the same class name and add styles to them. For example, if we want to add styles to all elements with the class name "header" in HTML, we can use the following code:
.header { font-size: 24px; font-weight: bold; }
In the above code, . means selecting the HTML element with the class name "header", The styles in {} will be added to the selected elements.
. has a wide range of usage scenarios. It can be used to select any HTML element with the same class name. For example, in web pages, we often use class names to control different types of paragraphs in articles, such as quotes, titles, text, etc. By using the .selector, we can add different styles to these different paragraph types.
2. The function and usage scenarios of >
is another symbol in CSS. Its function is to select direct child elements. For example, if we want to add styles to the child element h1 directly contained in the element div in HTML, we can use the following code:
div > h1 { font-size: 28px; color: #333; }
In the above code, > means selecting the direct child element h1 under the div element, The styles in {} will only apply to the h1 element and not to other child elements under the div element.
has relatively few usage scenarios. It is mainly used to select HTML elements with deeply nested structures, such as tables in web pages. In tables, we often use nested structures. By using the > selector, we can quickly and effectively control the style in the table.
3. The difference between the two
. and > are both symbols in CSS selectors. The difference between them is:
- different objects: . Used to select HTML elements with the same class name, while > is used to select direct child elements under the parent element.
- Different usage scenarios: . is suitable for selecting any HTML element with the same class name, while > is mainly used for selecting HTML elements with a deeper nested structure.
- Different priorities: . has a lower priority than >, which means that if an element is selected by both . and > selectors, then the style of the > selector will override the style of the . selector.
4. Summary
. and > in CSS respectively represent selecting HTML elements with the same class name and direct child elements under the parent element. The two have different objects and usage scenarios. For front-end developers, proficiently mastering the use of these two selectors can improve development efficiency and web page quality, which is worthy of attention and learning.
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