diff --git a/emhttp/plugins/dynamix/sheets/UserAdd-azure.css b/emhttp/plugins/dynamix/sheets/UserAdd-azure.css
deleted file mode 100644
index d61999a7c..000000000
--- a/emhttp/plugins/dynamix/sheets/UserAdd-azure.css
+++ /dev/null
@@ -1,15 +0,0 @@
-span#dropbox {
-    border: 1px solid #606e7f;
-    border-radius: 5px;
-    background: #edeaef;
-    padding: 28px 12px;
-    line-height: 72px;
-    margin-right: 16px;
-}
-.usage-disk.sys {
-    display: inline-block;
-    width: 10rem;
-    top: 1.2rem;
-    margin-left: 12px;
-    border-radius: 4px;
-}
diff --git a/emhttp/plugins/dynamix/sheets/UserAdd-black.css b/emhttp/plugins/dynamix/sheets/UserAdd-black.css
deleted file mode 100644
index 49dbffcda..000000000
--- a/emhttp/plugins/dynamix/sheets/UserAdd-black.css
+++ /dev/null
@@ -1,15 +0,0 @@
-span#dropbox {
-    border: 1px solid #f2f2f2;
-    border-radius: 5px;
-    background: #262626;
-    padding: 28px 12px;
-    line-height: 72px;
-    margin-right: 16px;
-}
-.usage-disk.sys {
-    display: inline-block;
-    width: 10rem;
-    top: 0.2rem;
-    margin-left: 12px;
-    border-radius: 4px;
-}
diff --git a/emhttp/plugins/dynamix/sheets/UserAdd-gray.css b/emhttp/plugins/dynamix/sheets/UserAdd-gray.css
deleted file mode 100644
index 23b1704ba..000000000
--- a/emhttp/plugins/dynamix/sheets/UserAdd-gray.css
+++ /dev/null
@@ -1,15 +0,0 @@
-span#dropbox {
-    border: 1px solid #606e7f;
-    border-radius: 5px;
-    background: #121510;
-    padding: 28px 12px;
-    line-height: 72px;
-    margin-right: 16px;
-}
-.usage-disk.sys {
-    display: inline-block;
-    width: 10rem;
-    top: 1.2rem;
-    margin-left: 12px;
-    border-radius: 4px;
-}
diff --git a/emhttp/plugins/dynamix/sheets/UserAdd-white.css b/emhttp/plugins/dynamix/sheets/UserAdd-white.css
deleted file mode 100644
index bb397fe17..000000000
--- a/emhttp/plugins/dynamix/sheets/UserAdd-white.css
+++ /dev/null
@@ -1,15 +0,0 @@
-span#dropbox {
-    border: 1px solid #1c1c1c;
-    border-radius: 5px;
-    background: #e8e8e8;
-    padding: 28px 12px;
-    line-height: 72px;
-    margin-right: 16px;
-}
-.usage-disk.sys {
-    display: inline-block;
-    width: 10rem;
-    top: 0.2rem;
-    margin-left: 12px;
-    border-radius: 4px;
-}
diff --git a/emhttp/plugins/dynamix/sheets/UserAdd.css b/emhttp/plugins/dynamix/sheets/UserAdd.css
index b93690329..65e010430 100644
--- a/emhttp/plugins/dynamix/sheets/UserAdd.css
+++ b/emhttp/plugins/dynamix/sheets/UserAdd.css
@@ -1,3 +1,27 @@
+:root {
+    --useradd-dropbox-border-color: #f2f2f2;
+    --useradd-dropbox-bg-color: #262626;
+    /* non-color vars are possible too */
+    --useradd-usage-disk-sys-top: 0.2rem;
+}
+
+.Theme--sidebar {
+    --useradd-usage-disk-sys-top: 1.2rem;
+}
+
+.Theme--azure {
+    --useradd-dropbox-border-color: #606e7f;
+    --useradd-dropbox-bg-color: #edeaef;
+}
+.Theme--gray {
+    --useradd-dropbox-border-color: #606e7f;
+    --useradd-dropbox-bg-color: #121510;
+}
+.Theme--white {
+    --useradd-dropbox-border-color: #1c1c1c;
+    --useradd-dropbox-bg-color: #e8e8e8;
+}
+
 i.top {
     position: absolute;
     padding-top: 4px;
@@ -6,3 +30,19 @@ i.top {
 i#showPass.checked {
     opacity: 0.5;
 }
+
+span#dropbox {
+    border: 1px solid var(--useradd-dropbox-border-color);
+    border-radius: 5px;
+    background: var(--useradd-dropbox-bg-color);
+    padding: 28px 12px;
+    line-height: 72px;
+    margin-right: 16px;
+}
+.usage-disk.sys {
+    display: inline-block;
+    width: 10rem;
+    top: var(--useradd-usage-disk-sys-top);
+    margin-left: 12px;
+    border-radius: 4px;
+}