Made a bunch of changes.

Create a config array to set common configuration used by the
script.

Created a method to calculate the elapsed time and return it with a
friendly description.

Changed the location of the <style> tag. This tag does not need to be
inside the <head> tag, the specification does not require that. But you
surely can't have more than one <html> tag, because this is the document
root.

Added a few more CSS classes to become easier to change the styles. And
so made the user status as a ribbon to have nice look by default.

And as last point, cleaned the code.
Just added my name to credits.