JSFiddle - React, Tailwind, and code Playground

HTML

The code in the JS window is actually BASH Script.

Purpose:
Verify whether an email domain is real or not by checking for an MX record.

Prerequisites:
none

Location:
/usr/local/bin/mx/mx.sh

To make it system-wide:
sudo ln -s /usr/local/bin/mx/mx.sh /usr/local/bin/mx

Remember to make script Executeable
sudo chmod +x /usr/local/bin/mx/mx.sh

To run command, enter:
mx

JavaScript

#! /bin/bash

LBLUE='\033[1;35m' # Set the colour (or use one in the list below by replacing the `1;35`)
echo -e "${LBLUE} Enter mail domain and press [ENTER]:\e[0m" # User-friendly request for input
read MAIL # Wait for input and Assign input to Variable `MAIL`
echo $MAIL >> /usr/local/bin/mx/mx.log # Keep a log file recording all queries
host -t mx $MAIL # Output the query
exit 0

# Blue      	  0;34
# Green         0;32
# Cyan   	      0;36
# Red           0;31
# Purple        0;35
# Brown         0;33
# Light Gray    0;37
# White         1;37
# Dark Gray     1;30
# Light Blue    1;34
# Light Green   1;32
# Light Cyan    1;36
# Light Red     1;31
# Yellow        1;33