.card flex rules break in Internet Explorer 10-11

Created by: HowlingEverett

The card flex shorthand rule is:

.card {
   flex: 1 0 0;
}

In Internet Explorer, the flex-basis rule of 0 causes the cards to ignore the flex-grow rule and size based on horizontal content-width.

Replacing the rule with:

.card {
  flex: 1 0 1px;
}

fixes the issue in IE and still works as expected in other browsers (cards grow to fill the container but maintain equal width in relation to each other.)