diff --git a/app/views/submissions/show.html.haml b/app/views/submissions/show.html.haml
--- a/app/views/submissions/show.html.haml
+++ b/app/views/submissions/show.html.haml
@@ -87,7 +87,7 @@
           %td.text-right
             %strong Compiler result
           %td
-            %button.btn.btn-info.btn-xs{type: 'button', data: {toggle: 'modal', target: '#compiler'}}
+            %button.btn.btn-info.btn-sm{type: 'button', data: {toggle: 'modal', target: '#compiler'}}
               view
         %tr
           %td.text-right
@@ -95,7 +95,7 @@
           %td
             = @task.status_str if @task
             - if @current_user.admin?
-              = link_to "rejudge", rejudge_submission_path, data: {remote: true}, class: 'btn btn-info btn-xs'
+              = link_to "rejudge", rejudge_submission_path, data: {remote: true}, class: 'btn btn-info btn-sm'
         - if @current_user.has_role?('ta')
           %tr
             %td.text-right
@@ -108,11 +108,11 @@
               - if @submission.tag_model?
                 YES
                 - if @current_user.has_role?('ta')
-                  = link_to "remove model status", set_tag_submission_path(@submission, tag: :default), class: 'btn btn-warning btn-xs'
+                  = link_to "remove model status", set_tag_submission_path(@submission, tag: :default), class: 'btn btn-warning btn-sm'
               - else
                 No
                 - if @current_user.has_role?('ta')
-                  = link_to "set as model solution", set_tag_submission_path(@submission, tag: :model), class: 'btn btn-success btn-xs'
+                  = link_to "set as model solution", set_tag_submission_path(@submission, tag: :model), class: 'btn btn-success btn-sm'
 
 
 .modal.fade#compiler{tabindex: -1,role: 'dialog'}