I would not be sure that Sophie is flashy (in fact, I'd suspect that she's classic).
The difference between a flashy and classic dog is actually a matter of
genetics. There is some basic information about that on our coat colour inheritance page at
www.boxerworld.com/coat_colour
In short though, boxers have two genes that are relevant here - S for solid coat colour (which never means completely solid colour) and an allele of s for white markings (actually the extreme white spotting allele sw). Every pup gets one of these genes from each parent. If the dog gets two copies of S, then it will be classic. If it gets one S and one sw, then it will be flashy. And if it gets two copies of sw, it will be white or nearly all white (better described as ultra flashy).
In most cases, we can just look at the dog and tell what it's genetic makeup is. A classic boxer usually has white on the toes, chest, tip of tail, and
possibly a little on the chin and face. Flashy usually has white feet (not just toes), perhaps some distance up the legs, white chest and belly, white on the face, and possibly a white collar also. Ultra-flashy, of course, is usually wholly or nearly wholly white.
Sophie though might be classic, or she might be flashy (and I'd lean toward classic). She's what often is termed "semi-flashy". She has white toes only (suggests classic), white chest only (again, suggests classic) and non-extensive white on the face (could be flashy, might be classic - it is not clear which). In short, it is not obvious just by looking at her which set of genes she carries. Of course, there is no
genetic "semi-flashy" category - the dog either carries the sw gene or it doesn't. But when you can't be sure just from looking, then semi-flashy is the obvious descriptor. The only way you'd ever know for sure (obviously not recommended) is by repeated breeding with males that are certainly classic.