fix comment and top-menu placement regressions

client/src/app/menu/menu.component.scss

@@ -26,6 +26,10 @@ menu {
     overflow-y: auto;
   }
 
+  .top-menu {
+    flex-grow: 1;
+  }
+
   .logged-in-block {
     height: 100px;
     background-color: rgba(255, 255, 255, 0.15);

client/src/app/videos/+video-watch/comment/video-comment.component.scss

@@ -54,7 +54,7 @@
         &:not(.linkified-url) {
           @include disable-default-a-behaviour;
 
-          color: #000;
+          color: var(--mainForegroundColor);
 
           font-weight: $font-semibold;
         }
@@ -73,7 +73,7 @@
         margin-right: 10px;
 
         &:hover {
-          color: #000;
+          color: var(--mainForegroundColor);
         }
       }
     }

client/src/app/videos/+video-watch/video-watch.component.scss

@@ -386,6 +386,7 @@
 
 my-video-comments {
   display: inline-block;
+  width: 100%;
   margin-bottom: 20px;
 }