[Glitch] Fix various issues around OpenGraph representation of media

Port front-end changes (except for audio player) from 662a49dc3f to glitch-soc

Signed-off-by: Thibaut Girka <thib@sitedethib.com>

app/javascript/flavours/glitch/styles/basics.scss

@@ -66,6 +66,35 @@ body {
     }
   }
 
+  &.player {
+    padding: 0;
+    margin: 0;
+    position: absolute;
+    width: 100%;
+    height: 100%;
+    overflow: hidden;
+
+    & > div {
+      height: 100%;
+    }
+
+    .video-player video {
+      width: 100%;
+      height: 100%;
+      max-height: 100vh;
+    }
+
+    .media-gallery {
+      margin-top: 0;
+      height: 100% !important;
+      border-radius: 0;
+    }
+
+    .media-gallery__item {
+      border-radius: 0;
+    }
+  }
+
   &.embed {
     background: lighten($ui-base-color, 4%);
     margin: 0;