ui: 修复一些显示问题

packages/ui-default/components/discussion/comments.page.styl

@@ -29,6 +29,13 @@ $downvote-color = red
     border-top: 0
 
 .dczcomments__reply
+  >.media
+    // FIXME doesn't work on IE 11
+    display: flex
+
+    >.media__body
+      width: calc(100% - (50px + 0.625rem))
+
   &:last-child
     >.media
       padding-bottom: 0
@@ -36,7 +43,7 @@ $downvote-color = red
 .dczcomments__item > .media
   display: flex
   >.media__body
-    max-width: calc(100% - 6.5em);
+    max-width: calc(100% - 6.5em)
 
 .dczcomments__supplementary
   float: left

packages/ui-default/components/problem/tag.page.styl

@@ -4,6 +4,8 @@
   list-style: none !important
   font-size: 0
   word-break: keep-all
+  display: flex
+  flex-wrap: wrap
 
 .problem__tag
   display: inline-block
@@ -13,11 +15,15 @@
   padding: 0 !important
 
 .problem__tag-item
-  padding: rem(0px)
+  padding: 0 10px !important
   margin-left: rem(3px)
   margin-bottom: rem(5px)
+  line-height: 30px !important
   &:hover
     text-decoration: none
+  > span
+    display: flex
+    align-items: center
 
 .problem__tag-link
   display: inline-block