none

// mixin.less

.border-radius(@radius){
    -webkit-border-radius: @radius;
       -moz-border-radius: @radius;
            border-radius: @radius;
}

.transition(@duration;@type){
    -webkit-transition: all @duration @type;
       -moz-transition: all @duration @type;
         -o-transition: all @duration @type;
            transition: all @duration @type;
}

.box-shadow(@y;@x;@size;@color){
    -webkit-box-shadow: @arguments;
       -moz-box-shadow: @arguments;
            box-shadow: @arguments;
}

//style.less
@import "../mixins.less";

div {
    .border-radius(3px);
    .box-shadow(0;0;10px; #ccc);
    .transition(500ms, ease-in);

    &-inner {
        color: red;
    }
}