terminology What is the meaning of “cascading” in CSS?

HTML element was not designed to have tags that would help format the page. You were only supposed to write the markup for the web page. The definition of CSS on this page is an original definition written by the TechTerms.com team. If you would like to reference this page or cite this definition, please use the green citation links above.

• The style definitions are normally saved in external .css files.
• Let’s say you have a 1200 page website that took you months to complete.
• CSS provides five special universal property values for controlling inheritance.
• Browsers, like Firefox, Chrome, or Edge, are designed to present documents visually, for example, on a computer screen, projector, or printer.

Specificity between layers doesn’t matter, but specificity within a single layer still does. CSS is a style sheet language used for formatting content in HTML webpages. CSS style sheets can define the appearance and formatting of text, tables, and other elements separately from the content itself. Styles may be found within a webpage’s HTML file or in a separate document referenced by multiple webpages.

How to Apply Your CSS

Let’s say you have a 1200 page website that took you months to complete. Then you decide to change the font, the size, the background, the appearance of tables, etc. everywhere on the site. If you engineered your site appropriately with CSS, you could do this by editing one linked CSS file that has all your appearance (format) rules in one place.

CSS modules now have version numbers, or levels, such as CSS Color Module Level 5. CSS is among the core languages of the open web and is standardized across Web browsers according to W3C specifications. Previously, the development of various parts of CSS specification was done synchronously, which allowed the versioning of the latest recommendations. There will never be a CSS3 or a CSS4; rather, everything is now CSS without a version number.

The effect of CSS location

A document is usually a text file structured using a markup language — HTML is the most common markup language, but you may also come across other markup languages such as SVG or XML. Sets the property value applied to a selected element to be the same as that of its parent element. Also significant here is the concept of inheritance, which means that some CSS properties by default inherit values set on the current element’s parent element and some don’t. This can also cause some behavior that you might not expect. An external style sheet is used to define the style for many HTML pages. I do of course make sure to tell them that it’s not a problem for the style sheets to be fighting each other, that’s the way the language was designed.

You will find that you quickly learn some values, whereas others you will need to look up. The individual property pages on MDN give you a quick way to look up properties and their values when you forget or when you want to know what else you can use as a value. As we have mentioned before, CSS is a language for specifying how documents are presented to users — how they are styled, laid out, etc. However, the web would be a boring place if all websites looked like that. Using CSS, you can control exactly how HTML elements look in the browser, presenting your markup using whatever design you like. First of all, we are only interested in the first seven rules of this example, and as you’ll notice, we have included their specificity values in a comment before each one.

How Does CSS Work?

If you had put the styles into the HTML, you would have to adjust each and every one of your 1200 HTML pages. By using CSS, changes can be made fast and easy simply by editing a few rules and lines in the global stylesheet. Before CSS, these changes were more difficult, expensive, and very time-consuming. Cascading Style Sheets (CSS) describe the visual style and presentation of a document, most commonly web sites. One purpose of CSS is to separate the presentation of a document from the structure and content (although it is possible to embed CSS within the structure as well).

Connect and share knowledge within a single location that is structured and easy to search. Our exhaustive CSS reference for seasoned Web developers describes every property and concept of CSS. You might have seen a website that fails to load completely and has a white background color with most of the text being blue and black. This means that the CSS part of the web page didn’t load correctly or it doesn’t exist altogether.

Introducing the CSS Cascade

Understanding origin precedence is key to understanding the cascade. There is a special piece of CSS that you can use to overrule all of the above calculations, even inline styles – the ! This flag is used to make an individual property and value pair the most specific rule, thereby overriding the normal rules of the cascade, including normal inline styles.

Headings will look larger than regular text, paragraphs break onto a new line and have space between them. Links are colored and underlined to distinguish them from the rest of the text. The style definitions are normally saved in external .css files. Let’s now have a look at how the browser will calculate specificity.

CSS allows you to have every format rule defined for later use (here “format” means how things appear). So if you are writing a large website and you want a consistent appearance for every title, sub-title, how examples of code appear, how paragraphs are aligned, etc. then CSS is the way to go. Beyond managing formatting, CSS also lets you modularize resources web development css cascading across complex websites, providing uniform presentation across multiple web pages. That’s because a single CSS document can be referenced by as many web pages as you like. So what CSS actually does is allow you to separate your content from its presentation. HTML handles the content – meaning, the text, images, and other media your users will consume.

And CSS adds more sophisticated control over the way that content looks and behaves. Media queries enable you to apply different styles based on the characteristics of the device. Now that you have some understanding of what CSS is, let’s move on to Getting started with CSS, where you can start to write some CSS yourself. Presenting a document to a user means converting it into a form usable by your audience. Browsers, like Firefox, Chrome, or Edge, are designed to present documents visually, for example, on a computer screen, projector, or printer. CSS (Cascading Style Sheets) allows you to create great-looking web pages, but how does it work under the hood?

As we saw earlier in this lesson, a class selector has more weight than an element selector, so the properties defined in the class style block will override those defined in the element style block. User-agents, or browsers, have basic style sheets that give default styles to any document. Most browsers use actual stylesheets for this purpose, while others simulate them in code.