missing breakpoint at 480px?

Created by: tkittich

The document says

• Extra small devices (phones, up to 480px)
• Small devices (tablets, 768px and up)
• Medium devices (desktops, 992px and up)
• Large devices (large desktops, 1200px and up)

So it seems a breakpoint & media query for devices between 480px - 768px are missing.