There are many free CSS Frameworks that offer Responsive Design.

Using W3.CSS

A great way to create a responsive design, is to use a responsive style sheet, like W3.CSS

W3.CSS makes it easy to develop sites that look nice at any size!

W3.CSS Demo

Resize the page to see the responsiveness!

Example

 <!DOCTYPE html>
<html>
<meta name="viewport"
 content="width=device-width, initial-scale=1">
<link rel="stylesheet"
 href="https://www.w3schools.com/w3css/4/w3.css">
<body>

<div
 class="w3-container w3-blue">
  <h1>W3Schools 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>

To learn more about W3.CSS, read our W3.CSS Tutorial.

Bootstrap

Another popular framework is Bootstrap. It uses HTML and CSS to make responsive web pages:

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@5.3.3/dist/css/bootstrap.min.css"
  rel="stylesheet">
<script
  src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/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 dolor sit amet, consectetur adipisicing elit...</p>

  <p>Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris...</p>

  </div>
    <div class="col-sm-4">

  <h3>Column 2</h3>
      <p>Lorem ipsum dolor sit
  amet, consectetur adipisicing elit...</p>

  <p>Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris...</p>

  </div>
    <div class="col-sm-4">

  <h3>Column 3</h3>
      <p>Lorem ipsum dolor sit
  amet, consectetur adipisicing elit...</p>

  <p>Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris...</p>

  </div>
  </div>
</div>

</body>
</html>

To learn more about Bootstrap, go to our Bootstrap Tutorial.