diff --git a/src/Umbraco.Infrastructure/WebAssets/BackOfficeWebAssets.cs b/src/Umbraco.Infrastructure/WebAssets/BackOfficeWebAssets.cs
index 05171988cf..4ffa549c3e 100644
--- a/src/Umbraco.Infrastructure/WebAssets/BackOfficeWebAssets.cs
+++ b/src/Umbraco.Infrastructure/WebAssets/BackOfficeWebAssets.cs
@@ -48,19 +48,18 @@ namespace Umbraco.Cms.Infrastructure.WebAssets
         {
             // Create bundles
 
-            // TODO: I think we don't want to optimize these css if/when we get gulp to do that all for us
-            _runtimeMinifier.CreateCssBundle(UmbracoInitCssBundleName, true,
+            _runtimeMinifier.CreateCssBundle(UmbracoInitCssBundleName, false,
                 FormatPaths("lib/bootstrap-social/bootstrap-social.css",
-                "assets/css/umbraco.css",
+                "assets/css/umbraco.min.css",
                 "lib/font-awesome/css/font-awesome.min.css"));
 
-            _runtimeMinifier.CreateCssBundle(UmbracoUpgradeCssBundleName, true,
-                FormatPaths("assets/css/umbraco.css",
+            _runtimeMinifier.CreateCssBundle(UmbracoUpgradeCssBundleName, false,
+                FormatPaths("assets/css/umbraco.min.css",
                 "lib/bootstrap-social/bootstrap-social.css",
                 "lib/font-awesome/css/font-awesome.min.css"));
 
-            _runtimeMinifier.CreateCssBundle(UmbracoPreviewCssBundleName, true,
-                FormatPaths("assets/css/canvasdesigner.css"));
+            _runtimeMinifier.CreateCssBundle(UmbracoPreviewCssBundleName, false,
+                FormatPaths("assets/css/canvasdesigner.min.css"));
 
             _runtimeMinifier.CreateJsBundle(UmbracoPreviewJsBundleName, false,
                 FormatPaths(GetScriptsForPreview()));
diff --git a/src/Umbraco.Web.UI.Client/gulp/config.js b/src/Umbraco.Web.UI.Client/gulp/config.js
index bd4c406e0f..50d9ab80bc 100755
--- a/src/Umbraco.Web.UI.Client/gulp/config.js
+++ b/src/Umbraco.Web.UI.Client/gulp/config.js
@@ -23,10 +23,10 @@ module.exports = {
         // less files used by backoffice and preview
         // processed in the less task
         less: {
-            installer: { files: "./src/less/installer.less", watch: "./src/less/**/*.less", out: "installer.css" },
+            installer: { files: "./src/less/installer.less", watch: "./src/less/**/*.less", out: "installer.min.css" },
             nonodes: { files: "./src/less/pages/nonodes.less", watch: "./src/less/**/*.less", out: "nonodes.style.min.css"},
-            preview: { files: "./src/less/canvas-designer.less", watch: "./src/less/**/*.less", out: "canvasdesigner.css" },
-            umbraco: { files: "./src/less/belle.less", watch: "./src/**/*.less", out: "umbraco.css" },
+            preview: { files: "./src/less/canvas-designer.less", watch: "./src/less/**/*.less", out: "canvasdesigner.min.css" },
+            umbraco: { files: "./src/less/belle.less", watch: "./src/**/*.less", out: "umbraco.min.css" },
             rteContent: { files: "./src/less/rte-content.less", watch: "./src/less/**/*.less", out: "rte-content.css" }
         },
 
diff --git a/src/Umbraco.Web.UI.Client/gulp/tasks/dependencies.js b/src/Umbraco.Web.UI.Client/gulp/tasks/dependencies.js
index fea1e8255b..fdee5e7785 100644
--- a/src/Umbraco.Web.UI.Client/gulp/tasks/dependencies.js
+++ b/src/Umbraco.Web.UI.Client/gulp/tasks/dependencies.js
@@ -178,7 +178,7 @@ function dependencies() {
             "name": "flatpickr",
             "src":  [
                 "./node_modules/flatpickr/dist/flatpickr.min.js",
-                "./node_modules/flatpickr/dist/flatpickr.css",
+                "./node_modules/flatpickr/dist/flatpickr.min.css",
                 "./node_modules/flatpickr/dist/l10n/*.js"
             ],
             "base": "./node_modules/flatpickr/dist"
@@ -248,7 +248,7 @@ function dependencies() {
             "name": "spectrum",
             "src":  [
                 "./node_modules/spectrum-colorpicker2/dist/spectrum.js",
-                "./node_modules/spectrum-colorpicker2/dist/spectrum.css"
+                "./node_modules/spectrum-colorpicker2/dist/spectrum.min.css"
             ],
             "base": "./node_modules/spectrum-colorpicker2/dist"
         },
diff --git a/src/Umbraco.Web.UI.Client/src/common/directives/components/umbcolorpicker.directive.js b/src/Umbraco.Web.UI.Client/src/common/directives/components/umbcolorpicker.directive.js
index b8731c9c51..a6a26dbe57 100644
--- a/src/Umbraco.Web.UI.Client/src/common/directives/components/umbcolorpicker.directive.js
+++ b/src/Umbraco.Web.UI.Client/src/common/directives/components/umbcolorpicker.directive.js
@@ -1,4 +1,4 @@
-/**
+/**
 @ngdoc directive
 @name umbraco.directives.directive:umbColorPicker
 @restrict E
@@ -84,7 +84,7 @@
         ctrl.$onInit = function () {
 
             // load the separate css for the editor to avoid it blocking our js loading
-            assetsService.loadCss("lib/spectrum/spectrum.css", $scope);
+            assetsService.loadCss("lib/spectrum/spectrum.min.css", $scope);
 
             // load the js file for the color picker
             assetsService.load([
diff --git a/src/Umbraco.Web.UI.Client/src/common/directives/components/umbdatetimepicker.directive.js b/src/Umbraco.Web.UI.Client/src/common/directives/components/umbdatetimepicker.directive.js
index ed9c011d72..63319fedc2 100644
--- a/src/Umbraco.Web.UI.Client/src/common/directives/components/umbdatetimepicker.directive.js
+++ b/src/Umbraco.Web.UI.Client/src/common/directives/components/umbdatetimepicker.directive.js
@@ -100,7 +100,7 @@ Use this directive to render a date time picker
         ctrl.$onInit = function () {
 
             // load css file for the date picker
-            assetsService.loadCss('lib/flatpickr/flatpickr.css', $scope).then(function () {
+            assetsService.loadCss('lib/flatpickr/flatpickr.min.css', $scope).then(function () {
                 userService.getCurrentUser().then(function (user) {
 
                     // init date picker
diff --git a/src/Umbraco.Web.UI.Client/src/index.html b/src/Umbraco.Web.UI.Client/src/index.html
index ba330853fc..a74540ab74 100644
--- a/src/Umbraco.Web.UI.Client/src/index.html
+++ b/src/Umbraco.Web.UI.Client/src/index.html
@@ -1,4 +1,4 @@
-<!doctype html>
+<!doctype html>
 <html lang="en">
 <head>
     <base href="/belle/" />
@@ -6,7 +6,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
 
     <title ng-bind="locationTitle">Umbraco</title>
-    <link rel="stylesheet" href="assets/css/umbraco.css" />
+    <link rel="stylesheet" href="assets/css/umbraco.min.css" />
 </head>
 
 <body ng-class="{touch:touchDevice,emptySection:emptySection}" ng-controller="Umbraco.MainController" id="umbracoMainPageBody">
diff --git a/src/Umbraco.Web.UI.Client/src/views/content/umbpreview.html b/src/Umbraco.Web.UI.Client/src/views/content/umbpreview.html
index 3cdf1450fb..f2693ec57a 100644
--- a/src/Umbraco.Web.UI.Client/src/views/content/umbpreview.html
+++ b/src/Umbraco.Web.UI.Client/src/views/content/umbpreview.html
@@ -2,7 +2,7 @@
 <html>
 <head>
     <title>Loading</title>
-    <link href="/umbraco/assets/css/umbraco.css" type="text/css" rel="stylesheet">
+    <link href="/umbraco/assets/css/umbraco.min.css" type="text/css" rel="stylesheet">
 </head>
 <body class="content-column-body">
 </body>
diff --git a/src/Umbraco.Web.UI.NetCore/umbraco/UmbracoInstall/Index.cshtml b/src/Umbraco.Web.UI.NetCore/umbraco/UmbracoInstall/Index.cshtml
index 605e355894..faa649d09d 100644
--- a/src/Umbraco.Web.UI.NetCore/umbraco/UmbracoInstall/Index.cshtml
+++ b/src/Umbraco.Web.UI.NetCore/umbraco/UmbracoInstall/Index.cshtml
@@ -10,7 +10,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
 
     <title>Install Umbraco</title>
-    <link rel="stylesheet" href="assets/css/installer.css" />
+    <link rel="stylesheet" href="assets/css/installer.min.css" />
 </head>
 
 <body ng-class="{loading:installer.loading}" ng-controller="Umbraco.InstallerController" id="umbracoInstallPageBody">