less responsive mixin

gistfile1.less

/* Responsive hack - Bootstrap */
@screen-xs:                  300px;
@screen-xs-min:              @screen-xs;
@screen-phone:               @screen-xs-min;

// Small screen / tablet
// Note: Deprecated @screen-sm and @screen-tablet as of v3.0.1
@screen-sm:                  620px;
@screen-sm-min:              @screen-sm;
@screen-tablet:              @screen-sm-min;

// Medium screen / desktop
// Note: Deprecated @screen-md and @screen-desktop as of v3.0.1
@screen-md:                  992px;
@screen-md-min:              @screen-md;
@screen-desktop:             @screen-md-min;

// Large screen / wide desktop
// Note: Deprecated @screen-lg and @screen-lg-desktop as of v3.0.1
@screen-lg:                  1500px;
@screen-lg-min:              @screen-lg;
@screen-lg-desktop:          @screen-lg-min;

// So media queries don't overlap when required, provide a maximum
@screen-xs-max:              (@screen-sm-min - 1);
@screen-sm-max:              (@screen-md-min - 1);
@screen-md-max:              (@screen-lg-min - 1);

@xs: ~'(min-width: @{screen-xs-min}) and (max-width: @{screen-xs-max})';
@sm: ~'(min-width: @{screen-xs-min}) and (max-width: @{screen-sm-max})';
//@md: ~'(min-width: @{screen-md-min}) and (max-width: @{screen-md-max})';
@lg: ~'(min-width: @{screen-md-min})';
img.responsive{
    @media @sm{
        max-width:100%;height:auto;
    }
    
}