diff --git a/Gemfile.lock b/Gemfile.lock
index 7c594ab..445834d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -12,14 +12,13 @@ GEM
       citeproc (~> 1.0, >= 1.0.9)
       csl (~> 1.5)
     colorator (1.1.0)
-    concurrent-ruby (1.1.7)
+    concurrent-ruby (1.3.7)
     csl (1.5.1)
       namae (~> 1.0)
     csl-styles (1.0.1.10)
       csl (~> 1.0)
     ffi (1.13.1)
     ffi (1.13.1-java)
-    ffi (1.13.1-x64-mingw32)
     ffi (1.13.1-x86-mingw32)
     forwardable-extended (2.6.0)
     jekyll (3.6.3)
@@ -86,7 +85,7 @@ GEM
 PLATFORMS
   java
   ruby
-  x64-mingw32
+  x64-mingw-ucrt
   x86-mingw32
   x86-mswin32