code: function(props, val) {
        if (/^o/.test(typeof props)) {
          for(var prop in props) {
            var prefixed = u.prfx(prop);
            if (props.hasOwnProperty(prop)) {
              this.each(function(index, el) {
                el.style[prefixed] = props[prop];
              });
            }
          }
          return this;
        }
        else {
          return val === undefined ? (this.length ? getComputedStyle(this[0])[props] : null) : this.each(function(index, el) {
            var prefixed = u.prfx(props);
            el.style[prefixed] = val;
          });
        }
      }
docs: css method
  get or set css properties
  @param  {(string|object)} props - property name or object with names and values
  @param  {string}          [val] - property value
  @return {(string|object)}         property value or this