From the home page, click on any photo to open that gallery.
In the gallery page click on any photo, which will open a light box – photo viewer.
Use the small arrows to navigation left and right.
Click the small cross, bottom right to close the light box.
If you click the top right hand side icon, you will open the FULL SIZE photo. It is not advisable to do this as the full size image is much larger than the average screen.