Code walkthrough for practicing CSS3 selectors

CSS3 selector hands-on code

CSS3 selector is a very important part of web development, it can help us better select and control HTML elements. In this article, we will use concrete code examples to learn and practice the use of CSS3 selectors.

The first type of selector is the element selector. It selects by the tag name of the HTML element. For example, we can use the following code to select all paragraph elements:

p {
    color: red;
}

The above code will set the text color of all paragraph elements to red.

The second type of selector is the class selector. It selects by adding the class attribute to HTML elements. For example, we can use the following code to select all elements with the "box" class:

.box {
    width: 200px;
    height: 200px;
    background-color: blue;
}

The above code will set the width and height of all elements with the "box" class to 200 pixels, and the background color to blue color.

The third selector is the ID selector. It selects by adding id attributes to HTML elements. For example, we can use the following code to select the element with "id1":

#id1 {
    font-size: 18px;
    font-weight: bold;
}

The above code will set the font size of the element with "id1" to 18 pixels and make the font bold.

The fourth selector is the descendant selector. It works by selecting descendant elements of an HTML element. For example, we can use the following code to select all span elements under paragraph elements:

p span {
    text-decoration: underline;
}

The above code will underline all span elements within paragraph elements.

The fifth type of selector is the attribute selector. It selects by selecting HTML elements with specific attributes. For example, we can use the following code to select all elements with the "title" attribute:

[title] {
    color: green;
}

The above code will set the text color of all elements with the "title" attribute to green.

The above are sample codes for some common CSS3 selectors. By practicing these codes, we can better understand and master the usage of CSS3 selectors. Hope this article helps you!

The above is the detailed content of Code walkthrough for practicing CSS3 selectors. For more information, please follow other related articles on the PHP Chinese website!