[code] CRINKLE SPARK

Several Bootstrap components utilize z-index, the CSS property that helps control layout by providing a third axis to arrange content. We utilize a default z-index scale in Bootstrap that’s been designed to properly layer navigation, tooltips and popovers, modals, and more.
For faster mobile-friendly development, use responsive display classes for showing and hiding elements by device. Avoid creating entirely different versions of the same site, instead hide elements responsively for each screen size.