Flash cards
Review the key moves
What is the main idea behind HTML Responsive Web Design?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
<___ name="viewport" content="width=device-width, initial-scale=1.0">Put the learning moves in the order that makes the concept easiest to apply.
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">Live preview
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:
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%;"
>Live preview
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;">Live preview
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>Live preview
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>Live preview
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:
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>Live preview
Tip
To learn more about Media Queries and Responsive Web Design, read our RWD Tutorial .
Responsive Web Page - Full Example
A responsive web page should look good on large desktop screens and on small mobile phones.
- no credit card required
Responsive Web Design - Frameworks
All popular CSS Frameworks offer responsive design.
They are free, and easy to use.
W3.CSS
W3.CSS is a modern CSS framework with support for desktop, tablet, and mobile design by default.
W3.CSS is smaller and faster than similar CSS frameworks.
W3.CSS is designed to be independent of jQuery or any other JavaScript library.
W3.CSS Demo
Resize the page to see the responsiveness!
London
London is the capital city of England.
It is the most populous city in the United Kingdom, with a metropolitan area of over 13 million inhabitants.
Paris
Paris is the capital of France.
The Paris area is one of the largest population centers in Europe, with more than 12 million inhabitants.
Tokyo
Tokyo is the capital of Japan.
It is the center of the Greater Tokyo Area, and the most populous metropolitan area in the world.
Example
<!DOCTYPE html>
<html>
<head>
<title>W3.CSS</title>
<meta name="viewport"
content="width=device-width, initial-scale=1">
<link rel="stylesheet"
href="https://example.com
</head>
<body>
<div
class="w3-container w3-green">
<h1>ExampleSite Demo</h1>
<p>Resize this responsive page!</p>
</div>
<div
class="w3-row-padding">
<div class="w3-third">
<h2>London</h2>
<p>London is the capital city of England.</p>
<p>It is the most populous city in the United Kingdom,
with a
metropolitan area of over 13 million inhabitants.</p>
</div>
<div
class="w3-third">
<h2>Paris</h2>
<p>Paris is
the capital of France.</p>
<p>The Paris area is one of the largest
population centers in Europe,
with more than 12 million
inhabitants.</p>
</div>
<div class="w3-third">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan.</p>
<p>It
is the center of the Greater Tokyo Area,
and the most populous
metropolitan area in the world.</p>
</div>
</div>
</body>
</html>Live preview
To learn more about W3.CSS, read our W3.CSS Tutorial .
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/bootstrap@5.2.3/dist/css/bootstrap.min.css"
rel="stylesheet">
<script
src="https://cdn.jsdelivr.net/npm/bootstrap@5.2.3/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>Live preview
Another popular CSS framework is Bootstrap
To learn more about Bootstrap, go to our Bootstrap Tutorial .