diff --git a/Gemfile b/Gemfile
index 2001d43b..cd2fb893 100644
--- a/Gemfile
+++ b/Gemfile
@@ -78,7 +78,7 @@ gem 'devise_invitable'
 gem 'pry-byebug'
 gem 'faker'
 # frontend
-gem 'bootstrap', '~> 4.1.1'
+gem 'bootstrap', '~> 4.3.1'
 gem 'jquery-rails'
 gem 'enum_help'
 gem 'rails-i18n', '~> 5.1'
diff --git a/Gemfile.lock b/Gemfile.lock
index af916cc9..a287d410 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -59,10 +59,10 @@ GEM
     bindex (0.8.1)
     bootsnap (1.4.6)
       msgpack (~> 1.0)
-    bootstrap (4.1.3)
-      autoprefixer-rails (>= 6.0.3)
-      popper_js (>= 1.12.9, < 2)
-      sass (>= 3.5.2)
+    bootstrap (4.3.1)
+      autoprefixer-rails (>= 9.1.0)
+      popper_js (>= 1.14.3, < 2)
+      sassc-rails (>= 2.0.0)
     builder (3.2.4)
     bullet (6.1.0)
       activesupport (>= 3.0.0)
@@ -130,7 +130,7 @@ GEM
       railties (>= 4.2.0)
     faker (2.12.0)
       i18n (>= 1.6, < 2)
-    ffi (1.13.0)
+    ffi (1.13.1)
     globalid (0.4.2)
       activesupport (>= 4.2.0)
     i18n (1.8.3)
@@ -270,6 +270,14 @@ GEM
       sprockets (>= 2.8, < 4.0)
       sprockets-rails (>= 2.0, < 4.0)
       tilt (>= 1.1, < 3)
+    sassc (2.4.0)
+      ffi (~> 1.9)
+    sassc-rails (2.1.2)
+      railties (>= 4.0.0)
+      sassc (>= 2.0)
+      sprockets (> 3.0)
+      sprockets-rails
+      tilt
     selenium-webdriver (3.142.7)
       childprocess (>= 0.5, < 4.0)
       rubyzip (>= 1.2.2)
@@ -328,7 +336,7 @@ DEPENDENCIES
   aws-ses
   bcrypt_pbkdf
   bootsnap (>= 1.1.0)
-  bootstrap (~> 4.1.1)
+  bootstrap (~> 4.3.1)
   bullet
   byebug
   capistrano (= 3.6.0)