When you're done making a layout and you've uploaded it to your website, you may also want to match the CSS and background to this layout. Finding the color codes you'll be needing is not that hard, actually.
1. First, start by finding the layout, or image you want to have the HTML color code on. I'll be using this one:
2. Secondly, press the Dropper Tool, which looks like this: . And now, click where ever the color of yours is. (example below)
3. If you now take a look to the right, underneath "Materials", you'll see the color you just did choose. Click on that color (example below) ¨
4. A new window will appear. Take a look at the button, where it says HTML. Copy that code, and paste it in your CSS or where ever you needed this color.
. And now, click where ever the color of yours is. (example below) 
