In our contemporary society, digital texts circulate more readily and extend beyond page-bound formats to include interactive representations such as online newsprint with hyperlinks to audio and video files. This is to say that multimodality combined with digital technologies extends grammar to include voice, visual, and music, among other modes for articulating ideas beyond written language. In this paper, I discuss these multimodal designs in relation to a group of transcultural youth and their multilingual exchanges online. I examine patterns that reveal how their linguistic exchanges both drew from and extended beyond in-school literacy practices. Using discourse and multimodal analyses, I examine data from a 3-year ethnography that documents specific ways in which their multimodal design migrated across contexts and facilitated their social language development. In so doing, I describe their artistic approach to attending to language variety beyond code-switching through a process I identify as "linguistic layering". (Contains 8 notes and 3 figures.)