8괘, 입체적 8괘, 모양 속으로

https://youtu.be/7KXzVGoG6Yk?si=U4Db4B14doqLaBCt

https://youtu.be/ddsKtIPMPIo?si=aSDvkRTWOEmu_vug

https://youtu.be/padvvmrHdRI?si=Z90r11_8bo6NxD7G