diff --git a/core/modules/user/css/user.module.css b/core/modules/user/css/user.module.css
index 869d016..47aa140 100644
--- a/core/modules/user/css/user.module.css
+++ b/core/modules/user/css/user.module.css
@@ -6,16 +6,12 @@
   display: inline;
 }
 .password-strength__meter {
-  background-color: #ebeae4;
   height: 0.75em;
   margin-top: 0.5em;
 }
 .password-strength__indicator {
   height: 100%;
   width: 0%;
-  background-color: #77b259;
-  -webkit-transition: width 0.5s ease-out;
-  transition: width 0.5s ease-out;
 }
 input.password-confirm,
 input.password-field,
@@ -30,7 +26,6 @@ div.form-item div.password-suggestions {
   padding: 0.2em 0.5em;
   margin: 0.7em 0;
   max-width: 34.7em;
-  border: 1px solid #b4b4b4;
 }
 div.password-suggestions ul {
   margin-bottom: 0;
@@ -46,15 +41,3 @@ div.password-suggestions ul {
 [dir="rtl"] .password-parent {
   clear: right;
 }
-.password-strength__indicator.is-weak {
-  background-color: #e62600;
-}
-.password-strength__indicator.is-fair {
-  background-color: #e09600;
-}
-.password-strength__indicator.is-good {
-  background-color: #0074bd;
-}
-.password-strength__indicator.is-strong {
-  background-color: #77b259;
-}
diff --git a/core/modules/user/css/user.theme.css b/core/modules/user/css/user.theme.css
new file mode 100644
index 0000000..962b003
--- /dev/null
+++ b/core/modules/user/css/user.theme.css
@@ -0,0 +1,26 @@
+/**
+ * Password strength indicator.
+ */
+.password-strength__meter {
+  background-color: #ebeae4;
+}
+.password-strength__indicator {
+  background-color: #77b259;
+  -webkit-transition: width 0.5s ease-out;
+  transition: width 0.5s ease-out;
+}
+div.form-item div.password-suggestions {
+  border: 1px solid #b4b4b4;
+}
+.password-strength__indicator.is-weak {
+  background-color: #e62600;
+}
+.password-strength__indicator.is-fair {
+  background-color: #e09600;
+}
+.password-strength__indicator.is-good {
+  background-color: #0074bd;
+}
+.password-strength__indicator.is-strong {
+  background-color: #77b259;
+}
diff --git a/core/modules/user/user.libraries.yml b/core/modules/user/user.libraries.yml
index 037023a..8376351 100644
--- a/core/modules/user/user.libraries.yml
+++ b/core/modules/user/user.libraries.yml
@@ -5,6 +5,8 @@ drupal.user:
   css:
     component:
       css/user.module.css: {}
+    theme:
+      css/user.theme.css: {}
   dependencies:
     - core/jquery
     - core/drupal