Let's talk about how to write inheritance in CSS

CSS is a language used to design web page styles. As one of the most basic and important technologies in front-end development, mastering its syntax and features is crucial to developing high-quality web pages. In CSS, inheritance is a very useful mechanism that can make designing web page styles more concise and efficient. In this article, we will introduce how inheritance is written in CSS and how to use it to improve the maintainability of CSS code.

What is inheritance?

First, let us understand what inheritance in CSS is. Properties in CSS can be inherited, which means that when a property of an element is set, its child elements will automatically inherit its value. For example, if you set a font color on a parent element, its child elements will automatically inherit its color.

Inheritance can greatly simplify CSS code because it reduces the amount of duplicate code. By using inheritance, you can apply a style to multiple elements on the page without having to manually define the style in each element. This makes CSS code more concise and easier to manage and maintain.

How to use inheritance?

In CSS, using inheritance is very simple. You only need to define a property in the parent element and the child elements will automatically inherit the property. Here is a simple example:

.parent {
  color: red;
}

.child {
  font-size: 16px;
}

In this example, the .child element inherits the color property of .parent, so its font color will be red . Also, the .child element defines its own font size, so it will retain that attribute.

In some cases, you may want to prevent inheritance from happening. You can override inherited properties using the inherit keyword. For example:

.parent {
  color: red;
}

.child {
  font-size: inherit;
}

In this example, the .child element inherits the color property of .parent, but its font size is set to inherit, so it will inherit the font size of its parent element.

Another way to prevent inheritance is to use the initial keyword. This keyword sets the property to its default value. For example:

.parent {
  color: red;
}

.child {
  color: initial;
}

In this example, the .child element will no longer inherit the color property of .parent, but will be set to the default value of that property. By default, the color of text elements is black.

Advantages and Disadvantages of Inheritance

Although inheritance brings many advantages, it also has certain limitations and disadvantages. Here are some notes:

1. Inheritance is limited to certain properties. Not all properties can be made inheritable, such as gradients, background images, borders, etc.
2. Inheritance can lead to complex cascading rules. If there is multiple inheritance, you need to consider which property will take precedence, which can lead to code that is difficult to debug and maintain.
3. In some special cases, inheritance may cause unnecessary redrawing or reflowing, which will affect performance.

Conclusion

Inheritance in CSS is an extremely useful and powerful technique that can reduce duplicate code, improve the priority of cascading effects and the readability of code. Although it has some limitations and disadvantages, you should still learn and master inheritance in order to play its role in writing high-quality, easy-to-maintain code.

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