This is the Internet age, and you can find more people online than ever. Most people access websites for work, information, entertainment, financial and commercial activities, and more. And although people on the Internet want websites that work correctly, there's something to be said about making a website look good.

Which brings us to CSS. Web designers use CSS to improve the aesthetic of the websites they create. This article tackles the subject of CSS vs. CSS3. First, we will define both languages, then dedicate most of this article to the CSS and CSS3 differences.

So let’s begin by describing both languages.

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What is CSS?

CSS is an acronym, short for Cascading Style Sheets and is a stylesheet language used by web designers to create a style or make web page elements more attractive. Developed by the World Wide Web Consortium (also known as W3C), CSS is one of the essential skills that a web developer should have to build visually appealing websites.

Cascading Style Sheets lets web designers style elements created with a markup language (typically, that's HTML). In addition, CSS boasts a straightforward syntax, making it easier to learn and use.

CSS allows developers to add various attributes such as background color, text color, font size, and border size. In addition, developers can alter these values to customize the webpage’s visuals and create a more appealing aesthetic.

Key CSS Features

  • Custom Properties. CSS allows designers to declare and use custom properties. This feature is handy when using the same properties repeatedly for different elements.
  • Animations. CSS lets designers create simple web page animations. It's relatively straightforward; you can choose which features you want to animate.
  • Font and Text Properties. CSS gives designers access to many kinds of fonts to make the webpage look nicer. Examples include background color, font family, font size, font style, font-weight, text-align, and text-indent.
  • Alignment, Positioning, and Spacing. CSS lets you effortlessly align and position text, images, and other elements. You can also use properties such as letter-spacing and word-spacing to ensure that the web page text is easily readable.

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What is CSS3?

CSS3, also known as Cascading Style Sheets Level 3, is a more advanced version of CSS and the successor of CSS2. CSS3 is used for the same thing as CSS, namely to style web pages and make them more attractive and user-friendly. In addition, CSS3 incorporates more up-to-date features designed to increase efficiency and make it more convenient for developers to use.

Key CSS3 Features

  • Advanced Animations. Animations are one of the most eye-catching features you can add to a web page. And while CSS allows web designers to use animations, CSS3 ups the stakes with more complex animation properties such as transforms, transitions, and special effects.
  • Opacity. This property lets web designers make web page elements partially or fully transparent. You can define the elements’ opacity levels to make them fully opaque, transparent, or even see-through.
  • Rounded Corners. Rounded corners make selected web page elements look more professional and visually appealing. Before the introduction of the border-radius property, web developers had to spend lots of time writing lengthy code to round off an element's corners.
  • Text and Box Shadows. CSS3 features built-in support for text and box shadows, so web designers can easily apply shadowing to different text sections and even easily define the shadow's color, angle, and blur level.

As a result, there’s no need to Photoshop the shadowed text and place it as an image on the web page. The same holds for adding a shadow effect to elements, which you can easily do by using the box-shadow property.

What’s the Difference Between CSS and CSS3

So we’ve established that CSS3 is just the latest version of CSS. That’s terrific, but what sets it apart from its predecessor? The following table clearly illustrates the differences between CSS vs. CSS3.




Year Released



Media Queries

Doesn’t support

Supports responsive web design

Browser Support

No support for modern browsers, but it still works on older versions of Explorer or Chrome

Supported fully by all modern browsers

Compatibility Between Versions

Not compatible with CSS3

Backward compatible with CSS

Block Support

Supports single blocks only

Supports multi-column text blocks

Animation Use

It only allows basic animations and doesn't support transformation, text animation, transition, or 3D animations

It offers advanced animations and many customization options. It also supports text animation, transformation, and transition

Responsive Design

It doesn’t support media queries, thus not ideal for making responsive designs

Works with media queries, thus allowing responsive web design

Module Use

It doesn’t have modules

Can group CSS codes into convenient modules

Color Format

It uses an old standard color format

It offers different gradient colors and schemes like RGBA, HSLA, HSL, etc.


It provides average performance and requires high memory usage

It offers fast, excellent performance and doesn’t use as much memory

CSS vs. CSS3: A Comparison of Features

Although the above chart gives us a convenient summary of the fundamental differences between CSS and CSS3, there are sufficiently significant differences between many of their features that justify a closer look. Therefore, in some instances, we will cover the features we already mentioned in the chart but give them a closer look.

Let's call out a selection of web design features and see how they differ between CSS and CSS3.

  • Compatibility. CSS3 is CSS; it’s just a more advanced version. Therefore, any code you have written in CSS is valid in CSS3. Unfortunately, the reverse isn’t true.
  • Rounded Corners and Gradients. When CSS was released, developers used design images to create rounded corners with different gradients and structures. Unfortunately, CSS doesn't feature any particular property that allows web designers to make element corners round quickly. So instead, it's a painstaking process involving designing images to represent rounded corners, storing them on a server, then placing them on the web page.

In contrast, once CSS3 came out, developers only needed to add a simple code to achieve the same results. For instance, here is the code for a round border: {border-radius: 25px}. In addition, it’s now easier to set gradients using simple code like: gradBG { Background:linear-gradient(red,blue); }.

  • Lists in CSS vs. CSS3. Developers using CSS can create a different ordered or unordered list. In addition, web developers can set background colors or introduce custom images for a list-item marker. CSS can also tweak list types like circle, square, and disc.

But with CSS3, the display property already has the list-item specified in it. So web developers can introduce images against the list-item marker, although it doesn’t support numbering.

  • Text Effects and Animations. CSS animations use JavaScript and jQuery. It has no feature of layer design, nor are there any special effects such as text shadows, text selections, etc.

By comparison, CSS3 lets developers incorporate text-shadow to create a 3D effect. CSS3 also offers a flexible and continuous variation of the size or color of the text. In addition, CSS3 animations can run without JavaScript or Flash code. Also, developers using CSS3 can produce text designs using fewer lines of code, boosting web page loading speed.

  • Fonts. CSS ensures that all machines and browsers should display and use the same fonts so that the design doesn’t create an anomaly.

In CSS3, however, web developers can introduce more unique fonts instead of using web-safe labeled fonts through the HTML script.

  • Pseudo-classes. CSS supports pseudo-classes that let developers define a particular state of an HTML element. For example, developers can use the pseudo-class to highlight the links on a web page that a user has already clicked on or style an HTML element when the user's mouse hovers over it.

CSS3 also allows pseudo-classes. However, CSS3 pseudo-classes come with advanced functionalities. For instance, developers can target the child elements of a parent element dependent on their position relative to the parent.

  • Attribute Selector. CSS3 features the Selector concept, whereas CSS does not. Thus, rather than applying classes or IDs for creating styles, developers can use CSS3 to choose HTML elements in place of IDs and classes as attributes to be applied to CSS styles.
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About the Author

John TerraJohn Terra

John Terra lives in Nashua, New Hampshire and has been writing freelance since 1986. Besides his volume of work in the gaming industry, he has written articles for Inc.Magazine and Computer Shopper, as well as software reviews for ZDNet. More recently, he has done extensive work as a professional blogger. His hobbies include running, gaming, and consuming craft beers. His refrigerator is Wi-Fi compliant.

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