<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>content</title>
<style>
form:hover input {
display: block;
}
form {
border: 1px solid;
}
input {
display: none;
}
input:focus {
display: block;
}
</style>
</head>
<body>
<form action="">
<div>Заголовок</div>
<input placeholder="текст">
</form>
</body>
</html>