Error message
                    error evaluating function `floor`: math functions take numbers as parameters in variables.less on line 273, column 36
271| @navbar-margin-bottom:             @line-height-computed;
272| @navbar-border-radius:             @border-radius-base;
273| @navbar-padding-horizontal:        floor(@grid-gutter-width / 2);
274| @navbar-padding-vertical:          ((@navbar-height - @line-height-computed) / 2);
275| 
276| @navbar-default-color:             #777;