图片上传适配移动端: 调整popover size；调整title

src/components/Editor/index.css

     height: 28px;
   }
 }
+
+.comment-img-popover {
+  /* 一行显示3张图 */
+  width: 336px;
+  min-height: 100px;
+  margin: 0 auto;
+}
+
+.comment-img-title {
+  margin: 5px auto;
+}
+.comment-img-title-counter {
+  color: #666;
+  font-weight: 400;
+}
+
+@media (max-width: 575px) {
+  .comment-img-popover {
+    /* 一行显示2张图 */
+    width: 224px;
+  }
+  .comment-img-title-counter {
+    display: none;
+  }
+}

src/components/Editor/index.js

                         });
                       }}
                       content={
-                        <div
-                          style={{
-                            width: 336, // 一行显示3张
-                            minHeight: 100,
-                            margin: "0 auto"
-                          }}
-                        >
+                        <div className="comment-img-popover">
                           <Upload
                             onRef={node => (this.uploadRef = node)}
                             multiple={multiple}
                         </div>
                       }
                       title={
-                        <div style={{ margin: "5px auto" }}>
+                        <div className="comment-img-title">
                           <span>
                             {intl.get("editor.uploadTip")}
                             {maxUpload >= 2 ? (
-                              <span style={{ color: "#666", fontWeight: 400 }}>
+                              <span className="comment-img-title-counter">
                                 {intl.get("editor.uploadCount", {
                                   count: maxUpload - uploadFileList.length
                                 })}