Responsive web design is about creating web pages that look good on all devices!
A responsive web design will automatically adjust for different screen sizes and viewports.
What is Responsive Web Design?
Responsive Web Design is about using HTML and CSS to automatically resize, hide, shrink, or enlarge, a website, to make it look good on all devices (desktops, tablets, and phones):
Setting The Viewport
To create a responsive website, add the following <meta> tag to all your web pages:
Example
<meta name="viewport" content="width=device-width, initial-scale=1.0">
This will set the viewport of your page, which will give the browser instructions on how to control the page's dimensions and scaling.
Here is an example of a web page without the viewport meta tag, and the same web page with the viewport meta tag:
Without the viewport meta tag:
With the viewport meta tag:
Tip: If you are browsing this page on a phone or a tablet, you can click on the two links above to see the difference.
Responsive Images
Responsive images are images that scale nicely to fit any browser size.
Using the width Property
If the CSS width property is set to 100%, the image will be responsive and scale up and down:
Example
<img
src="img_girl.jpg" style="width:100%;">
Notice that in the example above, the image can be scaled up to be larger than its original size. A better solution, in many cases, will be to use the max-width property instead.
Using the max-width Property
If the max-width property is set to 100%, the image will scale down if it has to, but never scale up to be larger than its original size:
Example
<img
src="img_girl.jpg" style="max-width:100%;height:auto;">
Show Different Images Depending on Browser Width
The HTML <picture> element allows you to define different images for different browser window sizes.
Resize the browser window to see how the image below changes depending on the width:
Example
<picture>
<source srcset="img_smallflower.jpg" media="(max-width:
600px)">
<source srcset="img_flowers.jpg" media="(max-width:
1500px)">
<source srcset="flowers.jpg">
<img src="img_smallflower.jpg"
alt="Flowers">
</picture>
Responsive Text Size
The text size can be set with a "vw" unit, which means the "viewport width".
That way the text size will follow the size of the browser window:
Hello World
Resize the browser window to see how the text size scales.
Example
<h1 style="font-size:10vw">Hello World</h1>
Viewport is the browser window size. 1vw = 1% of viewport width. If the viewport is 50cm wide, 1vw is 0.5cm.
Media Queries
In addition to resize text and images, it is also common to use media queries in responsive web pages.
With media queries you can define completely different styles for different browser sizes.
Example: resize the browser window to see that the three div elements below will display horizontally on large screens and stack vertically on small screens:
- Left Menu
- Main Content
- Right Content
Example
<style>
.left, .right {
float: left;
width: 20%; /* The width is 20%, by default */
}
.main {
float: left;
width: 60%; /* The width is 60%, by default */
}
/* Use a media query to
add a breakpoint at 800px: */
@media screen and (max-width: 800px) {
.left,
.main, .right {
width: 100%; /* The width is 100%, when the viewport is 800px or smaller */
}
}
</style>
Tip: To learn more about Media Queries and Responsive Web Design, read the RWD Tutorial.
Responsive Web Page - Full Example
A responsive web page should look good on large desktop screens and on small mobile phones.
Responsive Web Design - Frameworks
All popular CSS Frameworks offer responsive design.
They are free, and easy to use.
Bootstrap
Another popular CSS framework is Bootstrap:
Example
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap 5
Example</title>
<meta charset="utf-8">
<meta name="viewport"
content="width=device-width, initial-scale=1">
<link
href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css"
rel="stylesheet">
<script
src="https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container-fluid p-5 bg-primary text-white
text-center">
<h1>My First Bootstrap Page</h1>
<p>Resize
this responsive page to see the effect!</p>
</div>
<div
class="container mt-5">
<div class="row">
<div
class="col-sm-4">
<h3>Column 1</h3>
<p>Lorem ipsum...</p>
</div>
<div
class="col-sm-4">
<h3>Column 2</h3>
<p>Lorem ipsum...</p>
</div>
<div
class="col-sm-4">
<h3>Column 3</h3>
<p>Lorem ipsum...</p>
</div>
</div>
</div>
To learn more about Bootstrap, go to the Bootstrap Tutorial.