3d linked list diagram

A 3D singly linked list with a header node. The header node is a light blue rectangular prism labeled "L" with only a "next" field (no data). It points via a solid red arrow to the first real data node. Each real data node consists of two horizontal segments: front light blue labeled "next", back light green labeled with numbers 10, 20, 30. Solid red arrows connect each "next" to the next node's light blue part. The last node's "next" is null (no arrow). Arranged horizontally, educational diagram style, clear labels, sharp arrowheads.