This module looks at the cascade and inheritance, all the selector types we have available, units, sizing, styling backgrounds and borders, debugging, and lots more. In the Introduction to HTML module, we covered what HTML is and how it is used to mark up documents. 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.
CSS is the language that transforms a basic HTML structure into a user-friendly and visually beautiful webpage. It can change the font, color, size, and spacing of content, split it into multiple columns, or add animations and other features. One of the goals of CSS is to allow users greater control over presentation. Someone who finds red italic headings difficult to read may apply a different style sheet.
Syntax
When we style a link, we need to target the (anchor) element. This has different states depending on whether it is unvisited, visited, being hovered over, focused via the keyboard, or in the process of being clicked (activated). You can use CSS to target these different states — the CSS below styles unvisited links pink and visited links green.
Try adding a rule to make a span red if it is inside a paragraph. You will know if you have it right because the span in the first paragraph will be red, but the one in the first list item will not change color. Before starting this topic, you should also be familiar with using computers and using the web passively (i.e., just looking at it, consuming the content). Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in HTML or XML (including XML dialects such as SVG, MathML or XHTML).
Selector
In our example, we have the color property, which can take various color values. 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. Different styles can be applied depending on the output device being used; for example, the screen version can be quite different from the printed version, so authors can tailor the presentation appropriately for each medium. Instead of versioning the CSS specification, W3C now periodically takes a snapshot of the latest stable state of the CSS specification and individual modules progress.
Nearly all browsers nowadays
support CSS and many other
applications do, too. To write CSS, you don’t need more than a
text editor, but there are many tools available that make it even easier. If you’re looking into less-well-used CSS selectors, you may also want to look at +, ~, and [attr] selectors, all of which can be very useful.
Display and Positioning
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). In this CSS tutorial, you’ll learn how to add CSS to visually transform HTML into eye-catching sites. This topic contains the following modules, in a suggested order for working through them.
- If you’re looking into less-well-used CSS selectors, you may also want to look at +, ~, and [attr] selectors, all of which can be very useful.
- It is worth remembering however that in a real site, you want to ensure that visitors know that a link is a link.
- Save the code below as index.html in a folder on your machine.
A plain HTML document is generally accessible to everyone — as you start to style that document it is important that you don’t make it less accessible. Your visitor may well be on a computer with a mouse or trackpad, or a phone with a touchscreen. Or they might be using a screen reader, which reads out the content of the document, or they may need to use much larger text, or be navigating the site using the keyboard only.
The fourth value sets the base color of the shadow.
Before CSS, nearly all presentational attributes of HTML documents were contained within the HTML markup. All font colors, background styles, element alignments, borders, and sizes had to be explicitly described, often repeatedly, within the HTML. CSS lets authors move much of that information to another file, the style sheet, resulting in considerably simpler HTML. And additionally, as more and more devices are able to access responsive web pages, different screen sizes and layouts begin to appear. Customizing a website for each device size is costly and increasingly difficult. The modular nature of CSS means that styles can be reused in different parts of a site or even across sites, promoting consistency and efficiency.
There are many more selectors to explore, and you can find a more detailed list in our Selectors guide. Elements.) In CSS, you choose which properties you want to affect in your rule. Use CSS to solve common problems provides links to sections of content explaining how to use CSS to solve very common problems when creating a web page. You should learn the basics of HTML before attempting any CSS. We recommend that you work through our Introduction to HTML module first.
Using a text editor, paste the three lines of CSS (above) into a new file. 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.
With the basics of the CSS language covered, the next CSS topic for you to concentrate on is styling text — one of the most common things you’ll do with CSS. Here we look at text styling fundamentals, including setting font, boldness, italics, line and letter spacing, drop shadows, and other text features. We round off the module by looking at applying custom fonts to your page, and styling lists and links. CSS (Cascading Styling Sheet) is the language that defines the presentation of a document written in a markup language like HTML.
For example, you can use CSS to alter the font, color, size, and spacing of your content, split it into multiple columns, or add animations and other decorative features. CSS can be used for very basic document text styling — for example, for changing the color and size of headings and links. It can be used to create a layout — for example, turning a single column of text into a layout with a main content area and a website development css cascading sidebar for related information. Have a look at the links in this paragraph for specific examples. Specificity refers to the relative weights of various rules.[17] It determines which styles apply to an element when more than one rule could apply. Based on the specification, a simple selector (e.g. H1) has a specificity of 1, class selectors have a specificity of 1,0, and ID selectors have a specificity of 1,0,0.
