var fourSquareOutline = function() { strokeWeight(5); line(200, 0, 200, 400); line(0, 200, 400, 200); }; fourSquareOutline(); var setRandomColour = function() { fill(random(255)); }; var drawSquare = function() { if(mouseX < 200 && mouseY < 200) { rect(0, 0, 200, 200); } else if (mouseX < 200 && mouseY > 200) { rect(0, 200, 200, 200); } else if (mouseX > 200 && mouseY < 200) { rect(200, 0, 200, 200); } else if (mouseX > 200 && mouseY > 200) { rect(200, 200, 200, 200); } }; var mouseClicked = function() { setRandomColour(); drawSquare(); };