Complex or Rules Lite?

Is White Box a complex game or a rules-lite game?
I haven't given much thought to such things until recently. I notice that some systems bill themselves as "rules lite" like it is a good thing. Gamers talk about crunchy mechanics and most of us have been through the "more complex equals more realistic" hoop. Verisimilitude gets brought into the equation and sometimes I'm not sure what we are talking about anymore.
Complexity can come about for more than one reason. While learning White Box, I recall thinking it was very complex (teaching it can be complex too). There are a number of dissimilar subsystems, seemingly incomplete explanations that assume knowledge I didn't have and not much in the way of examples. The game changes somewhat each time the PCs level up and at certain levels the whole scheme changes, examples include when the party gains access to "invisibility" and "raise dead".
Putting that aside and looking at the game as a "one-off", there are a lot of pieces to this puzzle. Before the game can begin, there is preparation necessary above that of figuring out the rules. A referee must build a world, or at least a dungeon level for the players to explore. Then there is character generation and equipping the character, i.e. shopping and spell memorization. The perils of exploration, resource management - light source, surviving traps - making saving throws, mapping and getting through stuck doors. Once an encounter happens, there is the possibility of combat, which may involve spell casting. Morale may affect hirelings and monsters as things go badly. Providing things go well, there will be treasure and experience gained. All this is likely to take place in a single evening of play. In a campaign all the pieces are in constant motion.
While it is true that the basic concept is to "describe what you want your character to do and roll the die", which is simplicity itself, having rules to make sure things are handled consistently from one similar situation to the next and make things fair between players adds complexity. White Box depends on the referee to handle many things that will occur outside the scope of the written rules and this may be seen as a kind of complexity, one requiring a more experienced referee. As incomplete as they may be, the original three little brown books together number 110 pages of rules. This is no easy body of material to master and commit to memory since many of the sub-systems use unique mechanics.
Perhaps a truly rules-lite system would be one without levels where character play remains the same from session to session. There is no universal mechanic in White Box to apply to all situations, but perhaps rules-lite systems are marked by such a universal mechanic. We generally think the labels "rules-lite" and "rulings not rules" go together, but maybe that isn't necessarily true either.
It seems I am a bit shaky on just what a "rules-lite' system is or isn't, so how can I tell if White Box is complex or rules-lite? Maybe it's both? Maybe it doesn't matter?