Lock your Blogspot post

This is a javascript code and more secure

<SCRIPT LANGUAGE="JavaScript">

<!-- Begin

var password = '555'

password=prompt('Please enter the password to enter this post:','');

if (password != '555') {

location.href='https://learnthinkfirst.blogspot.com/';

}

// End -->

</SCRIPT>

555 is a default one you can change your password

no error perfectly run 

once copy the code and open HTML view paste the code in first line and save 

once you lock your webpage to view this 

Enter your password click ok