How can I right to left the "characters remaining"

Hi

I use facebook Theme and I want to right to left the "characters remaining" in the wall section,

I get the style with firebug:

#thewire-characters-remaining {
  color: #333333;
  float: right;
  font-weight: bold;
  text-align: right;
}

I must change float in this rule, but I can't find Which file is located in? where is this style?