Retro Squares Background 2 #416
 Noise  CC 0

Retro Squares Background 2

Source GDJ

 More Textures
Retro Circles Background 4 No Black@2X #423
 Dark  CC 0

Retro Circles Background 4 No Black

Source GDJ

Abstract Tiled Background Extended 6 #517
 Noise  CC 0

Abstract Tiled Background Extended 6

Source GDJ

Prismatic Geometric Tessellation Pattern No Background@2X #552
 Noise  CC 0

Prismatic Geometric Tessellation Pattern No Background

Source GDJ

Prismatic Abstract Geometric Background 4 #271
 Noise  CC 0

Prismatic Abstract Geometric Background 4

Source GDJ

Axiom Pattern #330
 Grid  CC BY-SA 3.0

Not even 1kb, but very stylish. Gray thin lines.

Source Struck Axiom