Since we are setting "appearance: none" on our <select> elements, the
drop down arrow from the browser is hidden. This arrow doesn't fit in
visually though. This commit adds a new arrow from a simple data url
SVG. Its a dark triangle "pointing" downwards.
Note that we need to set the background to both the gradient and the
image here. Both use the "background-image" property for the graphic,
but since they are positioned differently we must use the general
"background" shorthand.
We depend un such modern things anyway, having these kinds of properties
are more confusing than helpful. Let's not give the impression that we
make any attempt to work in old browsers.
This makes it easier for integrators of vnc.html to write their own
input and button styles.
It's also positive to cut a bit off from the size of the large base.css.
Samuel Mannehed