code: function (css1, css2) {
      var ret = ''
      for (var arg in arguments) {
        for (var k in arguments[arg]) {
          if (arguments[arg][k] && ret.indexOf(k) === -1) {
            if (k.indexOf('*') === 0) {
              ret += arguments[arg][k]
            } else {
              ret += k + ':' + arguments[arg][k] + ';'
            }
          }
        }
      }
      return ret
    }
docs: format @args css1, css2, css3 to css inline style
  
  @param {Object} css1 - css inline declaration
  @param {Object} css2 - css inline declaration
  @param {Object} css3 - css inline declaration
  @param {Object} ...
  @return {String} css inline style
  if the key start with * the value is direcly appended to the inline style (which should be already inline style formatted)
  used if multiple occurences of the same key is needed