.Significance { border-left: 4px solid #aaa; background-color: #eee; padding: 0.5em 1em; } .Significance.Significance--success { border-left-color: #46B450; background-color: #e3efe3; } .Significance.Significance--failed { border-left-color: #dc3232; background-color: #f5ebec; }