How to compare hours in Shell script

I'm trying to write a simple script to check if the current hour is before or after 12:00 AM.

#!/bin/bash
var1=`date +"%T"` # error "not an integer"
var2='12:00:00'
if [ $var1 -lt $var2 ]; then # always false
    echo "Good morning!"
else
    echo "Good afternoon!"
fi

The error says that var1 must be an integer number, and the condition is always false. I would like some help please. Thank you very much.