Oops, it doesn't look like 'legs day' is a national day..

Other days

get funky

Get Funky Day
lumpy rug

Lumpy Rug Day
law

Law Day
gum

Gum Day
blanket fort

Blanket Fort Day
boy friend

Boy Friend Day
self appreciation

Self Appreciation Day
comfy

Comfy Day
singles

Singles Day
nae nae

Nae Nae Day