Creating proximity through monochromatic colors.
function setup() {
var canvas = createCanvas(500, 500);
canvas.parent('sketch');
colorMode(HSB);
background(98);
from = color(50, 90, 90);
to = color(20, 90, 90);
between = lerpColor(from, to, 0.5);
noStroke();
rectMode(CENTER);
fill(from);
rect(3 * width / 8, height / 2, width / 8, 3 * height / 8);
fill(between);
rect(width / 2, height / 2, width / 8, 3 * height / 8);
fill(to);
rect(5 * width / 8, height / 2, width / 8, 3 * height / 8);
}