Jill Giles of the San Antonio-based Giles-Parscale knows what design can do for a space and, more importantly, what well-designed space can do for a brand. When her design firm merged with partner Brad Parscale's Web marketing company in 2011, Giles made sure the new offices for Giles-Parscale sold the brand it was trying to build. "When we sell design, that design matters," Giles said of the firm's offices at 321 Sixth St., housed on a two-building property with a past life as a seismic testing...