Further style tweaks for embedded media

src/plugins/chatview/styles/chatbox.scss

@@ -185,9 +185,6 @@
                 }
             }
 
-            video {
-                width: 100%
-            }
             progress {
                 margin: 0.5em 0;
                 width: 100%

src/shared/chat/styles/message-body.scss

@@ -9,29 +9,30 @@ converse-chat-message-body {
             max-width: 95%;
         }
         @include media-breakpoint-up(md) {
-            max-width: 75%;
+            max-width: 70%;
         }
         @include media-breakpoint-up(lg) {
-            max-width: 66%;
+            max-width: 50%;
         }
         @include media-breakpoint-up(xl) {
-            max-width: 50%;
+            max-width: 40%;
         }
     }
 
     video {
         display: block;
+        max-height: 25em;
         @include media-breakpoint-down(sm) {
             max-width: 95%;
         }
         @include media-breakpoint-up(md) {
-            max-width: 75%;
+            max-width: 70%;
         }
         @include media-breakpoint-up(lg) {
-            max-width: 66%;
+            max-width: 50%;
         }
         @include media-breakpoint-up(xl) {
-            max-width: 50%;
+            max-width: 40%;
         }
     }
 }