Add_pet.css

input[type=text], input[type=password], input[type=email]{
    width: 100%;
    padding: 12px 20px;
    margin: 8px 0;
    display: inline-block;
    border: 1px solid #ccc;
    border-radius: 4px;
    box-sizing: border-box;
}

input[type=submit] {
    width: 100%;
    background-color: #4CAF50;
    color: white;
    padding: 14px 20px;
    margin: 8px 0;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

input[type=submit]:hover {
    background-color: #45a049;
}

div {
	width: 50%;
	margin: auto;
    border-radius: 5px;
    background-color: #f2f2f2;
    padding: 20px;
}

p.heading {
	font-size:40px;
	text-align: center;
}