How to change width of CubeGeometry with Three.js?

Question

I have a cube geometry and a mesh, and i don't know how to change the width (or height... i can change x, y and z though). Here's a snippet of what i have right now:

geometry = new THREE.CubeGeometry( 200, 200, 200 );
material = new THREE.MeshBasicMaterial( { color: 0xff0000, wireframe: true } );
mesh = new THREE.Mesh( geometry, material );
// WebGL renderer here

function render(){
    mesh.rotation.x += 0.01;
    mesh.rotation.y += 0.02;
    renderer.render( scene, camera );
}

function changeStuff(){
    mesh.geometry.width = 500; //Doesn't work.
    mesh.width = 500; // Doesn't work.
    geometry.width = 500; //Doesn't work.
    mesh.position.x = 500// Works!!

    render();
}

Thanks!

EDIT

Found a solution:

mesh.scale.x = 500;

Answer 1

Just to complete comment and solution from question (and have an answer present with example code):

// create a cube, 1 unit for width, height, depth
var geometry = new THREE.CubeGeometry(1,1,1);

// each cube side gets another color
var cubeMaterials = [ 
    new THREE.MeshBasicMaterial({color:0x33AA55, transparent:true, opacity:0.8}),
    new THREE.MeshBasicMaterial({color:0x55CC00, transparent:true, opacity:0.8}), 
    new THREE.MeshBasicMaterial({color:0x000000, transparent:true, opacity:0.8}),
    new THREE.MeshBasicMaterial({color:0x000000, transparent:true, opacity:0.8}), 
    new THREE.MeshBasicMaterial({color:0x0000FF, transparent:true, opacity:0.8}), 
    new THREE.MeshBasicMaterial({color:0x5555AA, transparent:true, opacity:0.8}), 
]; 
// create a MeshFaceMaterial, allows cube to have different materials on each face 
var cubeMaterial = new THREE.MeshFaceMaterial(cubeMaterials); 
var cube = new THREE.Mesh(geometry, cubeMaterial);

cube.position.set(0,0,0);
scene.add( cube );
cube.scale.x = 2.5; // SCALE
cube.scale.y = 2.5; // SCALE
cube.scale.z = 2.5; // SCALE

A slightly advanced, dynamic example implemented here: https://www.matheretter.de/rechner/quader/ (still the same scaling)