Enchanting table at level 30: the bookshelf setup
A Torch, a carpet, a slab or any solid block in the gap switches that shelf off.

Carpet is a thin layer of wool to lay on floors, in 16 colors.
It is made with the Crafting Table from 2 × White Wool (other recipes also exist). As fuel it burns for 3.4 seconds in a Furnace, enough to smelt 0.3 items.
Two blocks of wool side by side make three carpets, and any carpet can be recolored with a dye. Carpet is only one sixteenth of a block high, so you walk over it without noticing, and hostile mobs cannot spawn on it.
Footsteps on carpet make no vibration for sculk sensors. Put a carpet on a Llama to decorate it with a colored blanket. Carpet burns and breaks quickly by hand.
White Dye + Any of #Orange Carpet, Magenta Carpet → White Carpet
2 × White Wool → 3 × White Carpet
// Slots with several items cycle through every accepted option.
A Torch, a carpet, a slab or any solid block in the gap switches that shelf off.
At the Crafting Table: 2 × White Wool give 3 × Carpet. Mining the block drops it. Sold by Villager: Shepherd (Apprentice).
It is a flat colored floor covering that stops mob spawns and muffles footsteps. Worn by: Llama and Trader Llama.
Yes. In a Furnace it burns for 3.4 seconds, enough to smelt 0.3 items.
Yes: fire can spread to it and destroy it, and lava nearby can set it alight.