classes and id's in CSS

class- best used for multiple elements when styling

id- best used to apply one specific instance and no where else

Div containers - should accounts for the border width's and the padding space in between the individual div box

1. When adding padding take note of how it disrupts the fixed container width, you would have to compensate the space in the fixed width's of the individual div layers

2. You can assign more than one class to an element by placing a space between each class that you want to use.

Ex: class="column bluebox"