diff --git a/app/assets/stylesheets/mobile/modal.scss b/app/assets/stylesheets/mobile/modal.scss
index 3111b601323..7114c9b2e1f 100644
--- a/app/assets/stylesheets/mobile/modal.scss
+++ b/app/assets/stylesheets/mobile/modal.scss
@@ -88,9 +88,14 @@
   form {
     margin-top: 20px;
     input[type=text] {
-      width: 500px;
+      box-sizing: border-box;
+      width: 100%;
     }
   }
+
+  .category-combobox {
+    width: 100%;
+  }
 }
 
 .flag-modal {
diff --git a/app/assets/stylesheets/mobile/topic-post.scss b/app/assets/stylesheets/mobile/topic-post.scss
index ef1bbbe8b33..42849b137e2 100644
--- a/app/assets/stylesheets/mobile/topic-post.scss
+++ b/app/assets/stylesheets/mobile/topic-post.scss
@@ -396,7 +396,6 @@ iframe {
 }
 
 #selected-posts {
-  float: left;
   width: 97%;
   padding-left: 3%;
   background-color: srgb-scale($tertiary, $secondary, 15%);