Your browser does not support grid, so will not be supported. Hover over your browser version to see if there is a way to enable potential support. Sorry, I am no longer able to justify working on making the layout work on older devices.
Note: ミクまん (Mikuman) is a joke/pun of the word 肉まん (Nikuman, or "meat bun") that has come up recently with the new Miku x Family Mart campaign featuring the Miku shaped meat buns.