diff --git a/.changeset/nasty-parrots-crash.md b/.changeset/nasty-parrots-crash.md
new file mode 100644
index 0000000000..bd5927e2fe
--- /dev/null
+++ b/.changeset/nasty-parrots-crash.md
@@ -0,0 +1,5 @@
+---
+"@primer/css": patch
+---
+
+Removed .css extension from @import and modified @primer/primitives to be output as Sass code.
diff --git a/src/color-modes/themes/dark.scss b/src/color-modes/themes/dark.scss
index e54694bdfd..e4fc1ce242 100644
--- a/src/color-modes/themes/dark.scss
+++ b/src/color-modes/themes/dark.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/dark.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/dark';
diff --git a/src/color-modes/themes/dark_colorblind.scss b/src/color-modes/themes/dark_colorblind.scss
index c6fde58572..7432cfdf80 100644
--- a/src/color-modes/themes/dark_colorblind.scss
+++ b/src/color-modes/themes/dark_colorblind.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/dark-colorblind.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/dark-colorblind';
diff --git a/src/color-modes/themes/dark_dimmed.scss b/src/color-modes/themes/dark_dimmed.scss
index a9d27c02d0..fb556d57f5 100644
--- a/src/color-modes/themes/dark_dimmed.scss
+++ b/src/color-modes/themes/dark_dimmed.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/dark-dimmed.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/dark-dimmed';
diff --git a/src/color-modes/themes/dark_high_contrast.scss b/src/color-modes/themes/dark_high_contrast.scss
index 1f5465581d..a1ffa85528 100644
--- a/src/color-modes/themes/dark_high_contrast.scss
+++ b/src/color-modes/themes/dark_high_contrast.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/dark-high-contrast.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/dark-high-contrast';
diff --git a/src/color-modes/themes/dark_tritanopia.scss b/src/color-modes/themes/dark_tritanopia.scss
index bf445751be..1862f39a0a 100644
--- a/src/color-modes/themes/dark_tritanopia.scss
+++ b/src/color-modes/themes/dark_tritanopia.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/dark-tritanopia.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/dark-tritanopia';
diff --git a/src/color-modes/themes/light.scss b/src/color-modes/themes/light.scss
index 805d12427d..7ac8d6ab58 100644
--- a/src/color-modes/themes/light.scss
+++ b/src/color-modes/themes/light.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/light.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/light';
diff --git a/src/color-modes/themes/light_colorblind.scss b/src/color-modes/themes/light_colorblind.scss
index 7a39eb3f19..354397a6f8 100644
--- a/src/color-modes/themes/light_colorblind.scss
+++ b/src/color-modes/themes/light_colorblind.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/light-colorblind.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/light-colorblind';
diff --git a/src/color-modes/themes/light_high_contrast.scss b/src/color-modes/themes/light_high_contrast.scss
index a6799fc8bc..77b1a7c4fd 100644
--- a/src/color-modes/themes/light_high_contrast.scss
+++ b/src/color-modes/themes/light_high_contrast.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/light-high-contrast.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/light-high-contrast';
diff --git a/src/color-modes/themes/light_tritanopia.scss b/src/color-modes/themes/light_tritanopia.scss
index 57c1f458cb..7ea6b8c22f 100644
--- a/src/color-modes/themes/light_tritanopia.scss
+++ b/src/color-modes/themes/light_tritanopia.scss
@@ -1 +1 @@
-@import '@primer/primitives/dist/css/functional/themes/light-tritanopia.css';
\ No newline at end of file
+@import '@primer/primitives/dist/css/functional/themes/light-tritanopia';