🖼️⬛️

#framed square #square in frame #contained square #picture frame square #square art

【⬜】

#nested squares #framed square #contained square #single nest #square border

🪆⬜

#nested squares #nesting doll squares #matryoshka squares #recursive squares #square concept #contained square

⬜️▣⬜️

#contained square #nested symbol #mathematical representation #U+25A3