HBO’s new Perry Mason is relentlessly grim. This is, after all, a show that began with a baby being kidnapped and murdered and somehow only got bleaker from there (suicides, mutilated corpses, violent stabbings, heroin-addicted prostitutes, etc). But no matter how dark these individual episodes got (and they got really, really dark) there was a glimmer of undeniable beauty in each installment, courtesy of the opening title cards. Sleek and elegantly placed, they have become a highlight not only of individual episodes but of the series as a whole and a true hallmark of this new, unquestionably more …