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HTML settings CSS

In web design and development, CSS is a very important technology. CSS (Cascading Style Sheets) provides a way to describe the style and layout of HTML documents.

CSS allows web designers to easily control the appearance and layout of elements in HTML documents. By separating style definition from HTML, CSS makes web pages easier to maintain and modify.

In this article, we will discuss how to set up CSS to control the style and layout of HTML documents.

Adding CSS to HTML Documents

To add CSS styles to HTML documents, there are a few different methods. Here are some of them:

Inline style sheets: Use the "style" attribute in the HTML element to define the style, like this:

This paragraph is in red.

While this method works for a small number of styles, it is not suitable for large websites because it requires repeated styling in every element. In addition, it is not easy to maintain.

Internal style sheet: Place CSS styles in the tag in the tag. For example:

p { color: red; } Copy after login

This method allows you to set multiple styles in the same document and have style control over the entire page . However, if you need to use the same style on multiple pages, you must copy and paste the style on each page.

External style sheet: Use the tag in the HTML document to reference the external CSS file. For example:

Copy after login

In this scenario, all styles are stored in a single CSS file and can be shared across multiple pages The document. This method is the most commonly used and is easy to maintain.

CSS Selectors

CSS selectors are patterns used to select specific elements. There are a variety of selectors available, including the following:

Element Selector: Selects a specific element. For example, to select all p elements:

p {

color: red; Copy after login }

ID selector: Selects elements with the specified ID. For example, to select elements with ID "header":

header { background-color: gray; Copy after login Copy after login }

Class Selector: Selects elements with the specified class. For example, select each element with class "intro":

.intro {

font-style: italic; Copy after login Copy after login }

Compound selector: composed of two or more simple selectors . For example, select all elements with class "intro" and which are p elements:

p.intro {

font-style: italic; Copy after login Copy after login }

CSS Layout

CSS Allowed You control the position and size of elements in an HTML document. Here are some of the most commonly used CSS layout properties:

Position: Use the position property to set an element to an "absolute", "relative" or "fixed" position:

position: absolute; position: relative; position: fixed;

Floating: Use the float attribute to float the element to the left or right:

float: left; float: right;

Display: Use the display attribute to control how elements are displayed, for example: block-level elements or inline elements:

display: block; display: inline;

Box model : Use padding, margin and border attributes to control the size and position of elements:

padding: 10px; margin: 10px; border: 1px solid black;

Responsive web page Design

Responsive web design is a technique used to create websites that are accessible on multiple devices. By using CSS media queries (Media Queries), you can optimize the layout of your website according to different device sizes and orientations.

For example, here is a simple responsive design that will change the layout when the device width falls below 600px:

@media screen and (max-width: 600px) { body {

background-color: lightblue; Copy after login } #header {

background-color: gray; Copy after login Copy after login } #nav {

width: 100%; Copy after login } #nav ul {

display: block; margin: 0; padding: 0; Copy after login } #nav li {

margin: 0; padding: 0; border-bottom: 1px solid white; Copy after login } }

Summary

CSS is a very important technology that provides a A method of describing the style and layout of an HTML document. To add CSS styles to HTML documents, there are several methods available, including inline style sheets, internal style sheets, and external style sheets. CSS selectors are patterns used to select specific elements, while CSS layout properties allow you to control the position and size of elements. Finally, responsive web design is a technique for creating websites that are accessible on multiple devices, using CSS media queries to optimize layout.