.formbox {
  width: calc(100% / 6 - 1px); /* 1px slack is required as workaround for IE sizing bug */
  float:left;
  text-align:center;
}

http://coboldinosaur.com/pages/css-calc-function.html

The CSS calc() function can be used anywhere a length, frequency, angle, time, number, or integer is required. It can be used to apply values for width/height; font-size; margins; padding; borders; shadows; border radius; text-indent;top/right/bottom/left(for position); and any place that a number is required.

6 even spaced elements across the page using calc() for sizing

css, design

CSS