CSS_DROPDOWN

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<!DOCTYPE html>
<html>
<head>
	<title>Dropdown Navbar</title>
	<style>
		.navbar {
  overflow: hidden;
  background-color: #333;
  }

.navbar a {
  float: left;
  font-size: 16px;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}


.dropdown {
  float: left;
  overflow: hidden;
}


.dropdown .dropdown_btn {
  font-size: 16px;
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit; 
  margin: 0;
}


.navbar a:hover, .dropdown:hover .dropdown_btn {
  background-color: #f25e13;
}


.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;
}


.dropdown_menu a:hover {
  background-color: #f25e13;
  color: white;
}


.dropdown:hover .dropdown_menu {
  display: block;
}
	</style>
</head>
<body>
<div class="navbar">
  <a href="#home">Home</a>
  <a href="#contact">Contact Us</a>
  <div class="dropdown">
    <button class="dropdown_btn">Dropdown Menu
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown_menu">
      <a href="#">Sub Menu 1</a>
      <a href="#">Sub Menu 2</a>
      <a href="#">Sub Menu 3</a>
    </div>
  </div>
</div>
</body>
</html>