A pack is heavy. It meets the ground on a base, and the light that describes it has to agree with that meeting. If the object hovers, and the only shadow is a soft disc that does not touch the base, you are looking at a render of a mood, not at a thing that could stand in a room.
Plant gravity is that meeting. Draw or photograph a continuous floor. Put the base on it. Let one side light rake across the edges so the thickness of the board, the tuck, and the recess are visible. The shadow is short and dark where the base touches, and it falls in the same direction as every other shadow in the picture.
The wrap does not create this. Paper glued over a box follows a structure that already stands. If the box has no base, no amount of finish will invent a floor.
How to check it
- Find the floor line. It should run under the base without a gap.
- Cover the glow. If the pack no longer feels supported, the shadow was doing the work of a pedestal.
- Check the edges. A side light should show thickness. Flat, even light hides whether the object is real.
Usage
.pack {
/* The floor is a plane, not a blurred disc. */
box-shadow:
0 1px 0 rgb(20 19 14 / 0.35),
0 10px 18px rgb(20 19 14 / 0.12);
}