php smtp mailer

I am attaching two functional codes to be based on them
the design must be beautiful simple and minimalist


Key Features:
- PHP version 7+
- No MySQL database needed
- Allow the usage of external SMTP server
- Allow multiple external smtps
- Allow HTML, Plain Text and Personalized emails
Other Advantages:
- As emails are sent out in several 'small lists', it use less resources on server
- Can pause/resume the process at anytime
- Simple and feasible to use with standard PHP mail() function
- Can set interval time/mails per interval to best match your server's performance
- Can be installed on most servers and does not require a database to use
- Password system prevent undesired users from accessing the script
Server Requirements:
- PHP version 7+
- A working PHP mail() function on the server
- Web browser that supports javascript
- To use external SMTP function, make sure your server have PEAR or phpMailer package installed