This is to display graph color legends or whatever has colors and needs some legends.. :)
<span class="legend legend-primary"></span> Primary
To color the legends, add .legend-[color-tag]
.legend-primary.legend-secondary.legend-accent.legend-neutral.legend-error.legend-caution.legend-success.legend-intensity-1.legend-intensity-2.legend-intensity-3.legend-intensity-4.legend-intensity-5
More info on color tags
The color can be customized by adding a background-color property to the legend
<span class="legend" style="background-color:pink;"></span> Primary