.cm-trailingspace {
  background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAACCAYAAAB/qH1jAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH3QUXCToH00Y1UgAAACFJREFUCNdjPMDBUc/AwNDAAAFMTAwMDA0OP34wQgX/AQBYgwYEx4f9lQAAAABJRU5ErkJggg==);
  background-position: bottom left;
  background-repeat: repeat-x;
}