My version for doing this challenge

Gerald Susanteo, one more step closer. To see the change in colors, you need to add the colors and their values in the loop as well. That way during each iteration it will randomly choose a color based off the Math.random() function * 256 for the color RGB range.

You can also make this a function to easily input the desired number length

let html = '';
let red;
let green;
let blue;
let randomRGB;

const main = document.querySelector('main');


const colorRange = numLength => {
  for(let i = 1; i <=numLength; i++){
    red = Math.floor(Math.random() * 256);
    green = Math.floor(Math.random() * 256);
    blue = Math.floor(Math.random() * 256);
    randomRGB = `rgb( ${red}, ${green}, ${blue} )`;
    html += `<div style="background-color: ${randomRGB}">${i}</div>`;

  }
  main.innerHTML = html;
}

colorRange(10);

The numbers do not change as you have enetered one between the div elements so it will always be one, you need to change that to be the varaible i.

The colours are all the same as red, green and blue variable are defined when the script loads, so they are only set once. If you want different colours on each iteration of the loop then you will need to define the colours in a function and then call the function each time, or you can just put the Math.floor code in 3 times into the loop like this: rgb(${Math.floor(Math.random() * 256)}, ${Math.floor(Math.random() * 256)}, ${Math.floor(Math.random() * 256)}