Learn CSS

"If you want to learn how to style and design web pages, you need to master CSS. CSS stands for Cascading Style Sheets, and it is the language that defines the appearance and layout of HTML elements. In this course, you will learn the basics of CSS, such as selectors, properties, values, units, and colors. You will also learn how to use CSS to create responsive web design, animations, transitions, and more. By the end of this course, you will be able to create beautiful and functional web pages using CSS."

CSS Transitions

CSS transitions are a powerful tool in web development that allow developers to animate changes to an element's CSS properties. CSS Transitions provide a way to add smooth, gradual changes to an element's style. It allows you to animate properties such as background color, font size, height, width, and more over a specified duration of time. This effect can be triggered by various events like hover, click, focus, and more. CSS transitions offer a simple way to add interactivity and make web pages feel more dynamic and engaging.



The syntax for a CSS transition is straightforward. It includes the transition-property, transition-duration, transition-timing-function, and transition-delay properties. The transition-property specifies which CSS property will be affected by the transition, and the transition-duration sets the length of time it takes for the transition to complete. The transition-timing-function defines the speed curve of the transition and how it accelerates and decelerates during the animation. The transition-delay property sets a time delay before the transition begins.

Here's the syntax for the transition for indusial properties:

/* transition-property */
transition-property: none | all | property;

/* transition-duration */
transition-duration: time;

/* transition-timing-function */
transition-timing-function: ease | linear | ease-in | ease-out | ease-in-out | cubic-bezier(n,n,n,n);

/* transition-delay */
transition-delay: time;


Shorthand syntax

The CSS syntax for a transition is:

transition: property duration timing-function delay;

Here's what each of these values means:

  1. property: The property that you want to transition.
  2. duration: The length of time that the transition should take.
  3. timing-function: The rate of change during the transition. This specifies the acceleration and deceleration of the transition. This can be a predefined timing function like linear or ease, or a custom timing function created using the cubic-bezier() function..
  4. delay: The amount of time to wait before the transition starts.


Multiple transitions

You can also specify multiple transitions using a comma-separated list:

transition: property1 duration1 timing-function1 delay1,
           property2 duration2 timing-function2 delay2,
           property3 duration3 timing-function3 delay3;



Here are some examples of using CSS transitions to create simple animations:

Change background color on hover 

.box {
 background-color: #ccc;
 transition: background-color 0.3s ease;
.box:hover {
 background-color: #f0f0f0;


Animate font-size on hover

.btn {
 font-size: 16px;
 transition: font-size 0.3s ease;
.btn:hover {
 font-size: 20px;


Scale up image on hover

img {
 transition: transform 0.3s ease;
img:hover {
 transform: scale(1.2);

In the first example, the background color of a box changes gradually when hovered over. In the second example, the font size of a button increases smoothly when hovered over. In the third example, the image scales up when the mouse is moved over it.


cubic-bezier() function to create a custom timing function:

You can also create your own custom easing functions using the cubic-bezier() function. This function takes four arguments, which represent the x and y values of two control points in a cubic bezier curve.

Example of a custom easing function:

.box {
 width: 100px;
 height: 100px;
 background-color: red;
 transition: width 2s cubic-bezier(0.5, 0.1, 0.5, 0.9);
.box:hover {
 width: 200px;

In this example, the cubic-bezier() function is used to create a custom easing function that starts slow, speeds up, then slows down again before finishing.


Browser Support

CSS transitions are supported by all modern browsers, including Chrome, Firefox, Safari, and Edge. However, some older browsers may not support all the transition properties or timing functions. When using transitions, it's important to test your website on different browsers to ensure a smooth user experience for everyone.

CSS transitions are a powerful tool for adding subtle animations and interactivity to your website. They allow you to create smooth, gradual changes to an element's style over a specified duration of time, triggered by various events. By using CSS transitions, you can make your website feel more dynamic and engaging, improving the user experience and making it more enjoyable for visitors.