Question

I’m wondering if there’s a simpler way to do this:

1. Position something centre-screen horizontally (easy).
2. Offset it’s position from the centre.

I normally achieve this by making a <div> with a width double of the amount I want to offset by, set it to margin: auto; and then put my desired element within this floated either left or right. This works fine, I just thought there might be a shorter way.

An an example, I might want to have a <div> positioned 80px to the left of the centre of the screen, like this:

                   

Answer 1

You can do something like this:

body { position: relative }

div {
  width: 300px;
  height: 250px;

  /* Origins from the screen center */
  position: absolute;
  top: 50%;
  left: 50%;

  margin-top: -125px; /* height / 2 */
  margin-left: -230px; /* (width / 2) - 80 */
  /* The margin left would be -150px but you want it to move 80 pixels to left */
}

Here’s an online example: http://jsfiddle.net/B4rDJ/2/ (thanks Purmou!)