diff --git a/frontend/src/components/dirent-detail/detail-comments-list.js b/frontend/src/components/dirent-detail/detail-comments-list.js
index 0d4ab2ab98..1e4bf5881b 100644
--- a/frontend/src/components/dirent-detail/detail-comments-list.js
+++ b/frontend/src/components/dirent-detail/detail-comments-list.js
@@ -176,7 +176,7 @@ class DetailCommentList extends React.Component {
           <MentionsInput
             value={this.state.comment}
             onChange={this.handleCommentChange}
-            placeholder={gettext('Add a comment.')}
+            placeholder={gettext('Add a comment...')}
             style={defaultStyle}
           >
             <Mention
diff --git a/frontend/src/components/file-view/comment-panel.js b/frontend/src/components/file-view/comment-panel.js
index 042172b302..3b8a6292e0 100644
--- a/frontend/src/components/file-view/comment-panel.js
+++ b/frontend/src/components/file-view/comment-panel.js
@@ -202,7 +202,7 @@ class CommentPanel extends React.Component {
           <MentionsInput
             value={this.state.comment}
             onChange={this.handleCommentChange}
-            placeholder={gettext('Add a comment.')}
+            placeholder={gettext('Add a comment...')}
             style={defaultStyle}
           >
             <Mention
@@ -315,7 +315,7 @@ class CommentItem extends React.Component {
           </div>
           <div className="seafile-edit-comment">
             <textarea className="edit-comment-input" value={this.state.newComment} onChange={this.handleCommentChange} clos="100" rows="3" warp="virtual"></textarea>
-            <Button className="comment-btn" color="success" size="sm" onClick={this.updateComment} id={item.id}>{gettext('Update')}</Button>{' '}
+            <Button className="comment-btn" color="primary" size="sm" onClick={this.updateComment} id={item.id}>{gettext('Update')}</Button>{' '}
             <Button className="comment-btn" color="secondary" size="sm" onClick={this.toggleEditComment}>{gettext('Cancel')}</Button>
           </div>
         </li>
diff --git a/frontend/src/components/review-list-view/review-comments.js b/frontend/src/components/review-list-view/review-comments.js
index 9114756912..2c759286b3 100644
--- a/frontend/src/components/review-list-view/review-comments.js
+++ b/frontend/src/components/review-list-view/review-comments.js
@@ -113,7 +113,7 @@ class ReviewComments extends React.Component {
           <textarea
             className="add-comment-input"
             value={this.state.comment}
-            placeholder={gettext('Add a comment.')}
+            placeholder={gettext('Add a comment...')}
             onChange={this.handleCommentChange}
             clos="100" rows="3" warp="virtual"
           ></textarea>
diff --git a/frontend/src/css/comments-list.css b/frontend/src/css/comments-list.css
index 7cf3410183..1aa59916d6 100644
--- a/frontend/src/css/comments-list.css
+++ b/frontend/src/css/comments-list.css
@@ -3,8 +3,7 @@
   display: flex;
   flex-direction: column;
 }
-.seafile-comment-title,
-.seafile-history-title {
+.seafile-comment-title {
   border-bottom: 1px solid #e5e5e5;
   min-height: 3em;
   line-height: 3em;
@@ -12,18 +11,15 @@
   display: flex;
   background-color: #fff;
 }
-.seafile-comment-title .seafile-comment-title-text,
-.seafile-history-title .seafile-history-title-text {
+.seafile-comment-title .seafile-comment-title-text {
   width: 100%;
   text-align: center;
   font-weight: 700;
 }
-.seafile-comment-title .seafile-comment-title-close,
-.seafile-history-title .seafile-history-title-close {
+.seafile-comment-title .seafile-comment-title-close {
   color: #b9b9b9;
 }
-.seafile-comment-title .seafile-comment-title-close:hover,
-.seafile-history-title .seafile-history-title-close:hover {
+.seafile-comment-title .seafile-comment-title-close:hover {
   color: #888;
 }
 .seafile-comment-item {