<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div class="container">
<form action="action_page.php">
<label for="fname">First Name</label>
<input type="text" id="fname" name="firstname" placeholder="Your name..">
<label for="lname">Last Name</label>
<input type="text" id="lname" name="lastname" placeholder="Your last name..">
<label for="gend">Gender</label>
<select id="gendr" name="sex">
<option value="male">Male</option>
<option value="female">Female</option>
<option value="other">Other</option>
</select>
<label for="subject">Subject</label>
<textarea id="subject" name="subject" placeholder="Write something.." style="height:200px"></textarea>
<input type="submit" value="Submit">
</form>
</div>
/* Style inputs with type="text", select elements and textareas */
input[type=text], select, textarea {
width: 100%; /* Full width */
padding: 12px; /* Some padding */
border: 1px solid #ccc; /* Gray border */
border-radius: 4px; /* Rounded borders */
box-sizing: border-box; /* Make sure that padding and width stays in place */
margin-top: 6px; /* Add a top margin */
margin-bottom: 16px; /* Bottom margin */
resize: vertical /* Allow the user to vertically resize the textarea (not horizontally) */
}
/* Style the submit button with a specific background color etc */
input[type=submit] {
background-color: #4CAF50;
color: white;
padding: 12px 20px;
border: none;
border-radius: 4px;
cursor: pointer;
}
/* When moving the mouse over the submit button, add a darker green color */
input[type=submit]:hover {
background-color: #45a049;
}
/* Add a background color and some padding around the form */
.container {
border-radius: 5px;
background-color: #f2f2f2;
padding: 20px;
}