A RESPONSIVE WEBPAGE
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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>HTML</title>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<style>
	.navbar {
	  overflow: hidden;
	  background-color: cyan;
	}
	.navbar a {
	  float: left;
	  display: block;
	  color: black;
	  text-align: center;
	  padding: 14px 16px;
	  text-decoration: none;
	  font-size: 20px;
	}
	.active {
	  background-color: #04AA6D;
	  color: white;
	}
	.navbar .icon {
	  display: none;
	}
	.dropdown {
	  float: left;
	  overflow: hidden;
	}
	.dropdown .btn {
	  font-size: 20px;    
	  border: none;
	  outline: none;
	  color: black;
	  padding: 14px 16px;
	  background-color: inherit;
	  font-family: inherit;
	  margin: 0;
	}
	.dropdown-menu {
	  display: none;
	  position: absolute;
	  background-color: #f9f9f9;
	  min-width: 160px;
	  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
	  z-index: 1;
	}
	.dropdown-menu a {
	  float: none;
	  color: black;
	  padding: 12px 16px;
	  text-decoration: none;
	  display: block;
	  text-align: left;
	}
	.navbar a:hover, .dropdown:hover .btn {
	  background-color: #555555;
	  color: white;
	}

	.dropdown-menu a:hover {
	  background-color: #cccccc;
	  color: black;
	}
	.dropdown:hover .dropdown-menu {
	  display: block;
	}
	.navbar input[type=text] {
	  
	  padding: 12px;
	  border: none;
	  margin-top: 3px;
	  margin-right: 5px;	 	 
}

    .row {
	  display: flex;
	  flex-wrap: wrap;
	  padding: 0 3px;
	}
	/* Create 3 columns in each row */
	.column {
	  flex: 40%;
	  max-width: 30%;
	  padding: 0 3px;
	}
	.column img {
	  margin-top: 8px;
	  vertical-align: middle;
	  width: 100%;
	}
    .testimonial {
      box-shadow: 0 6px 6px 0 rgba(0, 0, 0, 0.2);
	  background: #bbbbbb;
	  border-radius: 5px;
	  padding: 16px;
	  margin: 16px 0;
	  font-size: 20px;
   }
   /*clearning float */
   .testimonial::after {
	  content: "";
	  clear: both;
	  display: table;
	}
   .testimonial img {
      width: 150px;
	  height: 150px;
	  float: left;
	  border-radius: 50%;
   }   
  .testimonial h2 {
      color: blue;
	  font-size: 50px;
   }
   
   .footer .icon{
      font-size: 30px;
	  color: white;
	  background-color: blue;
	  padding: 8px 16px;
	  
	  }        
	.icon:hover {
	  color: blue;
	  background-color: white;
	}
   }
  
	@media screen and (max-width: 600px) {
	  .navbar a:not(:first-child), .dropdown .btn, .navbar input {
		display: none;
	  }
	  .navbar a.icon {
		float: right;
		display: block;
	  }
	}
	@media screen and (max-width: 600px) {
	  .navbar.responsive {position: relative;}
	  .navbar.responsive .icon {
		position: absolute;
		right: 0;
		top: 0;
	  }
	  .navbar.responsive a {
		float: none;
		display: block;
		text-align: left;
	  }
	  .navbar.responsive input { 
	    float: none;
		display: block;
		width: 90%;
		padding: 12px;
		border: 2px solid black;
		text-align: left;
	  }
	  .navbar.responsive .dropdown {float: none;}
	  .navbar.responsive .dropdown-menu {position: relative;}
	  .navbar.responsive .dropdown .btn {
		display: block;
		width: 100%;
		text-align: left;
	  }
	  
	  .column {
		flex: 100%;
		max-width: 100%;
	  }
	  .icon {
	    display: block;
	  }
	}
</style>
</head>
<body>
	<div class="navbar" id="nav">
	  <a href="#" class="active">Home</a>
	  <a href="#">course</a>
	  <a href="#">More</a>
	  <div class="dropdown">
		<button class="btn">Dropdown 
		  <i class="fa fa-caret-down"></i>
		</button>
		<div class="dropdown-menu">
		  <a href="#">Item 1</a>
		  <a href="#">Item 2</a>
		  <a href="#">Item 3</a>
		</div>
		<input type="text" placeholder="Search Here">
	  </div> 
	  <a href="javascript:void(0);" style="font-size:15px;" class="icon" onclick="myFunction()">&#9776;</a>
	</div>
	<div class="row">
		<div class="column">
			<img src="https://s3.ap-south-1.amazonaws.com/s3.studytonight.com/tutorials/uploads/pictures/1627557458-101156.jpeg" alt="img">
		</div>
		<div class="column">
			<h2> This is the place for some content</h2>
			<p> It is a responsive web page </p>
			<p>Responsive website design aims to design a webpage that looks good across every possible device. </p>
			<p>You can view everything without any confusion. The style may slightly vary according to the size of the device.</p> 
		</div>
	</div>
	<div class="testimonial">
	  <img src="https://s3.ap-south-1.amazonaws.com/s3.studytonight.com/tutorials/uploads/pictures/1628080137-.png" alt="image">
	  <p> The best learning guidance you get here. User friendly environment. Practise on project. Full on industrial support. </p>
	</div>
	<div class="footer">
	   <h2> Follow us on </h2>
		<button class="icon"><span class="fa fa-facebook"></span></button>
	   <button class="icon"><span class="fa fa-twitter"></span></button>
	   <button class="icon"><span class="fa fa-linkedin"></span></button>
   </div>
<script>
		function myFunction() {
		  var x = document.getElementById("nav");
		  if (x.className === "navbar") {
			x.className += " responsive";
		  } else {
			x.className = "navbar";
		  }
		}
</script>
</body>
</html>