input type email validation
use form tag for this process
after insert this code on your input tag
type="email" pattern="^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"
example:
<form action="login.php">
<div class="input-field"><input type="email" pattern="^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$" placeholder="Email" class="validate"></div>
<div class="input-field"><input type="password" placeholder="Password" class="validate"></div>
<button class="second-button">Sign in</button>
</form>