css does not report an error

CSS does not report errors

CSS is an extremely important part of front-end development. It is responsible for the presentation of web page styles. As a front-end developer, we have all encountered such a situation: there is obviously no problem with the CSS syntax, but the style cannot be displayed correctly on the page.

This situation usually makes developers very confused and confused, and even wastes a lot of time to locate the problem. In this article, we will discuss some common problems that cause CSS to not report errors but styles cannot be displayed correctly, and provide some solutions so that readers can quickly solve these problems.

1. CSS selector cannot match elements correctly

When writing CSS, we usually use selectors to locate elements to be styled. But sometimes, we may choose the wrong selector or use incorrect selectors to locate elements, causing CSS styles to not be displayed correctly.

For example, we might use a class selector to style an element bound by an id selector, or use an id selector to style an element bound by a class selector:

#my-class {
    color: red;
}

.my-id {
    font-size: 16px;
}

The CSS style written in this way will not be displayed correctly because the selector cannot correctly match the element. The correct writing should be:

#my-id {
    color: red;
}

.my-class {
    font-size: 16px;
}

2. CSS style is overridden by other styles

In the style sheet, we usually define multiple styles, but these styles may Interacting with each other, causing some styles to be overridden by other styles. This situation usually occurs when we view the element style in the browser and find that the style is displayed incorrectly, or only part of the style is effective.

For example, we may define multiple styles for the same element in a style sheet:

.my-class {
    color: red;
}

.my-class {
    font-size: 16px;
}

The style written in this way will only take effect for the later styles, while the previous styles will be affected by the later ones. The styles are covered. The correct way to write it is to use one style to define multiple attributes:

.my-class {
    color: red;
    font-size: 16px;
}

3. CSS style is inherited

CSS style has some attributes that can be inherited by the child elements of the element. inherited. For example, the color and font-size attributes can be inherited by child elements. Sometimes we don't want child elements to inherit certain styles, but we mistakenly define these styles on the parent element of the element, causing the child elements to inherit these styles, resulting in incorrect page display.

For example, we may define some styles in a div, but these styles are inherited by its child elements:

div {
    color: red;
    font-size: 16px;
}

The styles written in this way will cause the All child elements inherit these styles, including text, links, etc. The correct way to write it is to define the style separately for each element, rather than defining it on its parent element.

4. CSS style properties are overridden by browser default properties

The default behavior of the browser is to set some default style properties for some HTML elements, for example, The default style of the ul element sets the left indentation of the list items and the list item mark style.

Sometimes we may try to define these default attributes, but in fact these attributes have been overridden by the browser default values, causing our styles to not be displayed correctly.

For example, we may try to define a margin attribute for the ul element, but this attribute has been overridden by the browser default attribute:

ul {
    margin: 0;
}

The style written in this way will not be displayed correctly, because Browsers have set default indent and margin values ​​for ul elements. The correct way to write it is to use specific CSS properties to modify the value of the default property:

ul {
    padding: 0;
    list-style: none;
}

5. CSS style properties are not effective

Sometimes we define a property in CSS , but this attribute has no effect or is overridden by other styles. This usually happens when we write CSS styles in the wrong place, or don't include the stylesheet correctly in the template.

For example, we may define a style in the head, but this style does not take effect because we did not introduce the style sheet correctly in the template:

<head>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <div class="my-class">Hello World!</div>
</body>

The correct way to write it is The style sheet reference is placed in the head:

<head>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <div class="my-class">Hello World!</div>
</body>

The above are some common problems that cause CSS to not report an error but the style cannot be displayed correctly. If you encounter these problems, I hope this article can help you. Finally, we strongly recommend that you read the documentation and specifications carefully when writing CSS, and rationally organize and optimize your style sheets to make your styles easier to maintain and expand.

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