IE浏览器下float之间出现的小缝隙？

css如下：

全选复制放进笔记.report {
  width: 576px;
  padding: 10px 27px;
  background-color: #e6e5e5;
}
/* line 633, ../sass/other.scss */
.show_username {
  font-size: 14px;
  border-bottom: 10px;
}
/* line 638, ../sass/other.scss */
.comment_text {
  resize: none;
  width: 504px;
  height: 62px;
  border: 1px solid #139667;
}
/* line 645, ../sass/other.scss */
.submit_report {
  float: right;
  width: 66px;
  line-height: 68px;
  text-align: center;
  color: #fff;
  background-color: #139667;
}
.clearfix {
  *height: 1%;
}
/* line 4, ../sass/_once.scss */
.clearfix:after {
  clear: both;
  content: '.';
  display: block;
  height: 0;
  line-height: 0;
  overflow: hidden;
}