bastardized for me :D

_csswizardry.less

/*------------------------------------*\
    @CSSWIZARDRY-GRIDS
\*------------------------------------*/
/**
 * CONTENTS
 * VARIABLES............Your settings.
 * GRID SETUP...........Build the grid structure.
 * WIDTHS...............Build our responsive widths around our breakpoints.
 */

/*------------------------------------*\
    @VARIABLES
\*------------------------------------*/
/**
 * Set the spacing between your grid items.
 */
@gutter: 0;


/*------------------------------------*\
    @GRID SETUP
\*------------------------------------*/
/**
 * 1. Allow the grid system to be used on lists.
 * 2. Remove any margins and paddings that might affect the grid system.
 * 3. Apply a negative `margin-left` to negate the columns’ gutters.
 * 4. Remove whitespace caused by `inline-block` elements.
 */
.grid{
  list-style:none;                /* [1] */
  margin:0;                       /* [2] */
  padding:0;                      /* [2] */
  letter-spacing:-0.31em;         /* [4] */
  word-spacing:-0.43em;           /* [4] */
  text-align: center;
}


/**
 * 1. Cause columns to stack side-by-side.
 * 2. Space columns apart.
 * 3. Align columns to the tops of each other.
 * 4. Reinstate removed whitespace.
 * 5. Required to combine fluid widths and fixed gutters.
 */
.grid__item{
  width: 100%;
  display:inline-block;           /* [1] */
  padding-left:@gutter;           /* [2] */
  vertical-align:top;             /* [3] */
  letter-spacing:normal;          /* [4] */
  word-spacing:normal;            /* [4] */
  box-sizing:border-box;          /* [5] */
}

.grid--narrow {
  margin-left:-(@gutter / 2);

  > .grid__item, .gfield {
    padding-left:@gutter / 2;
  }
}

.grid--full {
  margin-left:0;

  > .grid__item {
    padding-left:0;
  }
}



/*------------------------------------*\
    @WIDTHS
\*------------------------------------*/
/**
 * These next bits get worked out for you.
 */

@mobile-start:      @screen-xs-min;
@lap-start:         @screen-sm-min;
@desk-start:        @screen-md-min;
@desk-lg-start:     @screen-lg-min;


/**
 * Create our widths, prefixed by the specified namespace.
 */
.device-type(@namespace: ~""){


/**
 * Whole
 */
.@{namespace}one-whole         { width:100%; }


/**
 * Halves
 */
.@{namespace}one-half          { width:50%; }


/**
 * Thirds
 */
.@{namespace}one-third         { width:33.333%; }
.@{namespace}two-thirds        { width:66.666%; }


/**
 * Quarters
 */
.@{namespace}one-quarter       { width:25%; }
.@{namespace}two-quarters      { width:50%; }
.@{namespace}three-quarters    { width:75%; }


/**
 * Fifths
 */
.@{namespace}one-fifth         { width:20%; }
.@{namespace}two-fifths        { width:40%; }
.@{namespace}three-fifths      { width:60%; }
.@{namespace}four-fifths       { width:80%; }


/**
 * Sixths
 */
.@{namespace}one-sixth         { width:16.666%; }
.@{namespace}two-sixths        { width:33.333%; }
.@{namespace}three-sixths      { width:50%; }
.@{namespace}four-sixths       { width:66.666%; }
.@{namespace}five-sixths       { width:83.333%; }


/**
 * Eighths
 */
.@{namespace}one-eighth        { width:12.5%; }
.@{namespace}two-eighths       { width:25%; }
.@{namespace}three-eighths     { width:37.5%; }
.@{namespace}four-eighths      { width:50%; }
.@{namespace}five-eighths      { width:62.5%; }
.@{namespace}six-eighths       { width:75%; }
.@{namespace}seven-eighths     { width:87.5%; }


/**
 * Tenths
 */
.@{namespace}one-tenth         { width:10%; }
.@{namespace}two-tenths        { width:20%; }
.@{namespace}three-tenths      { width:30%; }
.@{namespace}four-tenths       { width:60%; }
.@{namespace}five-tenths       { width:50%; }
.@{namespace}six-tenths        { width:60%; }
.@{namespace}seven-tenths      { width:70%; }
.@{namespace}eight-tenths      { width:80%; }
.@{namespace}nine-tenths       { width:90%; }


/**
 * Twelfths
 */
.@{namespace}one-twelfth       { width:8.333%; }
.@{namespace}two-twelfths      { width:16.666%; }
.@{namespace}three-twelfths    { width:25%; }
.@{namespace}four-twelfths     { width:33.333%; }
.@{namespace}five-twelfths     { width:41.666% }
.@{namespace}six-twelfths      { width:50%; }
.@{namespace}seven-twelfths    { width:58.333%; }
.@{namespace}eight-twelfths    { width:66.666%; }
.@{namespace}nine-twelfths     { width:75%; }
.@{namespace}ten-twelfths      { width:83.333%; }
.@{namespace}eleven-twelfths   { width:91.666%; }


}


/**
 * Our regular, non-responsive width classes.
 */
.device-type();

/**
 * Our breakpoint specific widths classes.
 */
@media only screen and (min-width:@mobile-start){
  .device-type(~"xs--");
}

@media only screen and (min-width:@lap-start){
  .device-type(~"sm--");
}

@media only screen and (min-width:@desk-start){
  .device-type(~"md--");
}

@media only screen and (min-width:@desk-lg-start){
  .device-type(~"lg--");
}