11 Nov What is CSS? Learn web development MDN

In this way, the same HTML document can be prepared identically for all possible media. Since the content and design are separate in this document, the code of the website is clearer. The related style language SASS offers even more possibilities, but it doesn’t entirely replace CSS.

what is css

If you need to change the format of a specific set of pages, it’s easy to do so with CSS. Just edit the corresponding CSS stylesheet and you’ll see changes applied to all the pages that are using that style sheet. While an internal style sheet is a nice way to have all the code in one file, it makes that file rather large and doesn’t allow for style changes to be applied globally across different web pages. You can see that if you wanted to make a change to an element across a few pages, it would be easy to make a mistake when you use an internal style sheet.

What is CSS used for and why do we need it?

As a web developer, the three main languages we use to build websites are HTML, CSS, and JavaScript. Together, we use these three languages to format, design, and program web pages. The reason we were able to access these elements in our JavaScript was because we had set unique attributes on them, to help us identify them.

  • But this data has to be arranged and formatted into a form that’s understandable by end-users who have a wide range of technical experiences and abilities.
  • More importantly, it enables you to do this independently of the HTML that makes up each web page.
  • This group is made of representatives of browser vendors and other companies who have an interest in CSS.
  • For example, if you want to change the colors of all the text on your website, you can do so by editing your CSS file instead of having to edit each individual web page.

Some of them have already reached Level 4 or are already approaching Level 5. Other modules that define entirely new functionality, such as Flexbox,[53] have been designated as Level 1 and some of them are approaching Level 2. Rather than by laboriously going through the document and changing the color for each individual h1 element. Values may be keywords, such as „center“ or „inherit“, or numerical values, such as 200px (200 pixels), 50vw (50 percent of the viewport width) or 80% (80 percent of the parent element’s width).

Declaration block

Whereas HTML largely determines textual content, CSS determines visual structure, layout, and aesthetics. HTML is a markup language, what is css and CSS is a style sheet language. CSS level 2 specification was developed by the W3C and published as a recommendation in May 1998.

what is css

You’ll see reference to these modules as you explore MDN. Many of the documentation pages are organized around a particular module. For example, you could take a look at the MDN reference to the Backgrounds and Borders module to find out what its purpose is and the properties and features it contains. In that module, you will also find a link to Specifications that defines the technology (also see the section below).

While you add text to a website using HTML and structure it semantically, you define the design of its content using CSS. Although HTML and CSS are used in combination, the CSS design instructions and the HTML elements exist separately from one another. This means that a machine can read an electronic document even without CSS.

what is css

Someone who finds red italic headings difficult to read may apply a different style sheet. Browser extensions like Stylish and Stylus have been created to facilitate the management of such user style sheets. Is the declaration, and again, “p” (meaning the HTML paragraph) is the selector. These same basic principles can be applied to change font sizes, background colors, margin indentations, and more on your web page by choosing the specific selector. There are many reasons why you’ll want to use CSS in web design.

An external style sheet is used to define the style for many HTML pages. CSS is used to style all HTML tags, including the document’s body, headings, paragraphs, and other pieces of text. CSS can also be used to style the display of table elements, grid elements, and images. You can apply the class of special to any element on your page that you want to have the same look as this list item.

You’ll notice quite a few differences between the two when it comes to overall presentation. With CSS, you see a change in font, font size, and font color. You also see a change in the format of the buttons and get an added blue background behind them. Each of these elements are possible because of cascading style sheets. In short, CSS is a design language that makes a website look more appealing than just plain or uninspiring pieces of text.