Hi to all,
I think the problem is you don't opened the 80/TCP port in firewall.
Like us, we followed all the steps 1 to 7, but in CentOS 7 you need to do one aditional step (before step 6 to be correct), you need to open port 80/TCP
in CentOS 7 you can do it whit that command:
sudo firewall-cmd --zone=public --add-port=80/tcp --permanent
sudo firewall-cmd --reload
Another thing... you have "httpd" and "mysql/mariadb" RUNNING after reboot? if NOT:
Centos7:
systemctl enable httpd.service
systemctl enable mariadb.service
reboot
It works for me, and if its posible, any moderator, can add that on the main guide :)