diff --git a/app/assets/javascripts/admin/components/customize-link.js.es6 b/app/assets/javascripts/admin/components/customize-link.js.es6
new file mode 100644
index 00000000000..79d8cc26f4a
--- /dev/null
+++ b/app/assets/javascripts/admin/components/customize-link.js.es6
@@ -0,0 +1,10 @@
+export default Ember.Component.extend({
+  router: function() {
+    return this.container.lookup('router:main');
+  }.property(),
+
+  active: function() {
+    const id = this.get('customization.id');
+    return this.get('router.url').indexOf(`/customize/css_html/${id}/css`) !== -1;
+  }.property('router.url', 'customization.id')
+});
diff --git a/app/assets/javascripts/admin/controllers/admin-customize-colors.js.es6 b/app/assets/javascripts/admin/controllers/admin-customize-colors.js.es6
index 636905c009a..4a6a58021bb 100644
--- a/app/assets/javascripts/admin/controllers/admin-customize-colors.js.es6
+++ b/app/assets/javascripts/admin/controllers/admin-customize-colors.js.es6
@@ -1,13 +1,4 @@
-/**
-  This controller supports interface for creating custom CSS skins in Discourse.
-
-  @class AdminCustomizeColorsController
-  @extends Ember.Controller
-  @namespace Discourse
-  @module Discourse
-**/
 export default Ember.ArrayController.extend({
-
   onlyOverridden: false,
 
   baseColorScheme: function() {
diff --git a/app/assets/javascripts/admin/controllers/admin-customize-css-html-show.js.es6 b/app/assets/javascripts/admin/controllers/admin-customize-css-html-show.js.es6
new file mode 100644
index 00000000000..01dc0da3259
--- /dev/null
+++ b/app/assets/javascripts/admin/controllers/admin-customize-css-html-show.js.es6
@@ -0,0 +1,76 @@
+const sections = ['css', 'header', 'top', 'footer', 'head-tag', 'body-tag',
+                  'mobile-css', 'mobile-header', 'mobile-top', 'mobile-footer' ];
+
+const activeSections = {};
+sections.forEach(function(s) {
+  activeSections[Ember.String.camelize(s) + "Active"] = Ember.computed.equal('section', s);
+});
+
+
+export default Ember.Controller.extend(activeSections, {
+  maximized: false,
+  section: null,
+
+  previewUrl: Discourse.computed.url("model.key", "/?preview-style=%@"),
+  downloadUrl: Discourse.computed.url('model.id', '/admin/size_customizations/%@'),
+
+  mobile: function() {
+    return this.get('section').startsWith('mobile-');
+  }.property('section'),
+
+  maximizeIcon: function() {
+    return this.get('maximized') ? 'compress' : 'expand';
+  }.property('maximized'),
+
+  saveButtonText: function() {
+    return this.get('model.isSaving') ? I18n.t('saving') : I18n.t('admin.customize.save');
+  }.property('model.isSaving'),
+
+  saveDisabled: function() {
+    return !this.get('model.changed') || this.get('model.isSaving');
+  }.property('model.changed', 'model.isSaving'),
+
+  needs: ['adminCustomizeCssHtml'],
+
+  undoPreviewUrl: Discourse.computed.url('/?preview-style='),
+  defaultStyleUrl: Discourse.computed.url('/?preview-style=default'),
+
+  actions: {
+    save() {
+      this.get('model').saveChanges();
+    },
+
+    destroy() {
+      const self = this;
+      return bootbox.confirm(I18n.t("admin.customize.delete_confirm"), I18n.t("no_value"), I18n.t("yes_value"), function(result) {
+        if (result) {
+          const model = self.get('model');
+          model.destroyRecord().then(function() {
+            self.get('controllers.adminCustomizeCssHtml').get('model').removeObject(model);
+            self.transitionToRoute('adminCustomizeCssHtml');
+          });
+        }
+      });
+    },
+
+    toggleMaximize: function() {
+      this.toggleProperty('maximized');
+    },
+
+    toggleMobile: function() {
+      const section = this.get('section');
+
+      // Try to send to the same tab as before
+      let dest;
+      if (this.get('mobile')) {
+        dest = section.replace('mobile-', '');
+        if (sections.indexOf(dest) === -1) { dest = 'css'; }
+      } else {
+        dest = 'mobile-' + section;
+        if (sections.indexOf(dest) === -1) { dest = 'mobile-css'; }
+      }
+      this.replaceWith('adminCustomizeCssHtml.show', this.get('model.id'), dest);
+    }
+  }
+
+});
diff --git a/app/assets/javascripts/admin/controllers/admin-customize-css-html.js.es6 b/app/assets/javascripts/admin/controllers/admin-customize-css-html.js.es6
deleted file mode 100644
index d71267589d4..00000000000
--- a/app/assets/javascripts/admin/controllers/admin-customize-css-html.js.es6
+++ /dev/null
@@ -1,69 +0,0 @@
-import showModal from 'discourse/lib/show-modal';
-
-export default Ember.ArrayController.extend({
-
-  undoPreviewUrl: function() {
-    return Discourse.getURL("/?preview-style=");
-  }.property(),
-
-  defaultStyleUrl: function() {
-    return Discourse.getURL("/?preview-style=default");
-  }.property(),
-
-  actions: {
-
-    /**
-      Create a new customization style
-
-      @method newCustomization
-    **/
-    newCustomization: function() {
-      var item = Discourse.SiteCustomization.create({name: I18n.t("admin.customize.new_style")});
-      this.pushObject(item);
-      this.set('selectedItem', item);
-    },
-
-    importModal: function() {
-      showModal('upload-customization');
-    },
-
-    /**
-      Select a given style
-
-      @method selectStyle
-      @param {Discourse.SiteCustomization} style The style we are selecting
-    **/
-    selectStyle: function(style) {
-      this.set('selectedItem', style);
-    },
-
-    /**
-      Save the current customization
-
-      @method save
-    **/
-    save: function() {
-      this.get('selectedItem').save();
-    },
-
-    /**
-      Destroy the current customization
-
-      @method destroy
-    **/
-    destroy: function() {
-      var _this = this;
-      return bootbox.confirm(I18n.t("admin.customize.delete_confirm"), I18n.t("no_value"), I18n.t("yes_value"), function(result) {
-        var selected;
-        if (result) {
-          selected = _this.get('selectedItem');
-          selected.destroy();
-          _this.set('selectedItem', null);
-          return _this.removeObject(selected);
-        }
-      });
-    }
-
-  }
-
-});
diff --git a/app/assets/javascripts/admin/models/site-customization.js.es6 b/app/assets/javascripts/admin/models/site-customization.js.es6
new file mode 100644
index 00000000000..655d15bf726
--- /dev/null
+++ b/app/assets/javascripts/admin/models/site-customization.js.es6
@@ -0,0 +1,31 @@
+import RestModel from 'discourse/models/rest';
+
+const trackedProperties = [
+  'enabled', 'name', 'stylesheet', 'header', 'top', 'footer', 'mobile_stylesheet',
+  'mobile_header', 'mobile_top', 'mobile_footer', 'head_tag', 'body_tag'
+];
+
+function changed() {
+  const originals = this.get('originals');
+  if (!originals) { return false; }
+  return _.some(trackedProperties, (p) => originals[p] !== this.get(p));
+}
+
+const SiteCustomization = RestModel.extend({
+  description: function() {
+    return "" + this.name + (this.enabled ? ' (*)' : '');
+  }.property('selected', 'name', 'enabled'),
+
+  changed: changed.property.apply(changed, trackedProperties.concat('originals')),
+
+  startTrackingChanges: function() {
+    this.set('originals', this.getProperties(trackedProperties));
+  }.on('init'),
+
+  saveChanges() {
+    return this.save(this.getProperties(trackedProperties)).then(() => this.startTrackingChanges());
+  },
+
+});
+
+export default SiteCustomization;
diff --git a/app/assets/javascripts/admin/models/site_customization.js b/app/assets/javascripts/admin/models/site_customization.js
deleted file mode 100644
index 19fcbad266e..00000000000
--- a/app/assets/javascripts/admin/models/site_customization.js
+++ /dev/null
@@ -1,116 +0,0 @@
-/**
-  Our data model for interacting with site customizations.
-
-  @class SiteCustomization
-  @extends Discourse.Model
-  @namespace Discourse
-  @module Discourse
-**/
-Discourse.SiteCustomization = Discourse.Model.extend({
-  trackedProperties: [
-    'enabled', 'name',
-    'stylesheet', 'header', 'top', 'footer',
-    'mobile_stylesheet', 'mobile_header', 'mobile_top', 'mobile_footer',
-    'head_tag', 'body_tag'
-  ],
-
-  description: function() {
-    return "" + this.name + (this.enabled ? ' (*)' : '');
-  }.property('selected', 'name', 'enabled'),
-
-  changed: function() {
-    var self = this;
-
-    if (!this.originals) { return false; }
-
-    var changed = _.some(this.trackedProperties, function (p) {
-      return self.originals[p] !== self.get(p);
-    });
-
-    if (changed) { this.set('savingStatus', ''); }
-
-    return changed;
-  }.property('enabled', 'name', 'originals',
-    'stylesheet', 'header', 'top', 'footer',
-    'mobile_stylesheet', 'mobile_header', 'mobile_top', 'mobile_footer',
-    'head_tag', 'body_tag'),
-
-  startTrackingChanges: function() {
-    var self = this;
-    var originals = {};
-    _.each(this.trackedProperties, function (prop) {
-      originals[prop] = self.get(prop);
-    });
-    this.set('originals', originals);
-  }.on('init'),
-
-  previewUrl: function() { return Discourse.getURL("/?preview-style=" + this.get('key')); }.property('key'),
-  disableSave: function() { return !this.get('changed') || this.get('saving'); }.property('changed'),
-
-  save: function() {
-    this.set('savingStatus', I18n.t('saving'));
-    this.set('saving',true);
-
-    var data = {
-      name: this.name,
-      enabled: this.enabled,
-      stylesheet: this.stylesheet,
-      header: this.header,
-      top: this.top,
-      footer: this.footer,
-      mobile_stylesheet: this.mobile_stylesheet,
-      mobile_header: this.mobile_header,
-      mobile_top: this.mobile_top,
-      mobile_footer: this.mobile_footer,
-      head_tag: this.head_tag,
-      body_tag: this.body_tag
-    };
-
-    var siteCustomization = this;
-    return Discourse.ajax("/admin/site_customizations" + (this.id ? '/' + this.id : ''), {
-      data: { site_customization: data },
-      type: this.id ? 'PUT' : 'POST'
-    }).then(function (result) {
-      if (!siteCustomization.id) {
-        siteCustomization.set('id', result.id);
-        siteCustomization.set('key', result.key);
-      }
-      siteCustomization.set('savingStatus', I18n.t('saved'));
-      siteCustomization.set('saving',false);
-      siteCustomization.startTrackingChanges();
-      return siteCustomization;
-    });
-  },
-
-  destroy: function() {
-    if (!this.id) return;
-    return Discourse.ajax("/admin/site_customizations/" + this.id, { type: 'DELETE' });
-  },
-
-  download_url: function() {
-    return Discourse.getURL('/admin/site_customizations/' + this.id);
-  }.property('id')
-});
-
-var SiteCustomizations = Ember.ArrayProxy.extend({
-  selectedItemChanged: function() {
-    var selected = this.get('selectedItem');
-    _.each(this.get('content'), function (i) {
-      i.set('selected', selected === i);
-    });
-  }.observes('selectedItem')
-});
-
-Discourse.SiteCustomization.reopenClass({
-  findAll: function() {
-    return Discourse.ajax("/admin/site_customizations").then(function (data) {
-      var content = [];
-      if (data) {
-        content = data.site_customizations.map(function(c) {
-          return Discourse.SiteCustomization.create(c);
-        });
-      }
-      return SiteCustomizations.create({ content: content });
-    });
-  }
-});
diff --git a/app/assets/javascripts/admin/routes/admin-customize-css-html-show.js.es6 b/app/assets/javascripts/admin/routes/admin-customize-css-html-show.js.es6
new file mode 100644
index 00000000000..dc38f3c51fb
--- /dev/null
+++ b/app/assets/javascripts/admin/routes/admin-customize-css-html-show.js.es6
@@ -0,0 +1,11 @@
+export default Ember.Route.extend({
+  model(params) {
+    const all = this.modelFor('adminCustomizeCssHtml');
+    const model = all.findProperty('id', parseInt(params.site_customization_id));
+    return model ? { model, section: params.section } : this.replaceWith('adminCustomizeCssHtml.index');
+  },
+
+  setupController(controller, hash) {
+    controller.setProperties(hash);
+  }
+});
diff --git a/app/assets/javascripts/admin/routes/admin-customize-css-html.js.es6 b/app/assets/javascripts/admin/routes/admin-customize-css-html.js.es6
index c76c7e9a43c..8bbd22a4565 100644
--- a/app/assets/javascripts/admin/routes/admin-customize-css-html.js.es6
+++ b/app/assets/javascripts/admin/routes/admin-customize-css-html.js.es6
@@ -1,5 +1,26 @@
+import showModal from 'discourse/lib/show-modal';
+import { popupAjaxError } from 'discourse/lib/ajax-error';
+
 export default Ember.Route.extend({
   model() {
-    return Discourse.SiteCustomization.findAll();
+    return this.store.findAll('site-customization');
+  },
+
+  actions: {
+    importModal() {
+      showModal('upload-customization');
+    },
+
+    newCustomization(obj) {
+      obj = obj || {name: I18n.t("admin.customize.new_style")};
+      const item = this.store.createRecord('site-customization', obj);
+
+      const all = this.modelFor('adminCustomizeCssHtml');
+      const self = this;
+      item.save().then(function() {
+        all.pushObject(item);
+        self.transitionTo('adminCustomizeCssHtml.show', item.get('id'), 'css');
+      }).catch(popupAjaxError);
+    }
   }
 });
diff --git a/app/assets/javascripts/admin/routes/admin-route-map.js.es6 b/app/assets/javascripts/admin/routes/admin-route-map.js.es6
index daf3b1ced6f..66d9ea4c795 100644
--- a/app/assets/javascripts/admin/routes/admin-route-map.js.es6
+++ b/app/assets/javascripts/admin/routes/admin-route-map.js.es6
@@ -16,7 +16,11 @@ export default {
 
     this.resource('adminCustomize', { path: '/customize' } ,function() {
       this.route('colors');
-      this.route('css_html');
+
+      this.resource('adminCustomizeCssHtml', { path: 'css_html' }, function() {
+        this.route('show', {path: '/:site_customization_id/:section'});
+      });
+
       this.resource('adminSiteText', { path: '/site_text' }, function() {
         this.route('edit', {path: '/:text_type'});
       });
diff --git a/app/assets/javascripts/admin/templates/components/customize-link.hbs b/app/assets/javascripts/admin/templates/components/customize-link.hbs
new file mode 100644
index 00000000000..dd3c4104c75
--- /dev/null
+++ b/app/assets/javascripts/admin/templates/components/customize-link.hbs
@@ -0,0 +1,5 @@
+<li>
+  <a href="/admin/customize/css_html/{{customization.id}}/css" class="{{if active 'active'}}">
+    {{customization.description}}
+  </a>
+</li>
diff --git a/app/assets/javascripts/admin/templates/customize-css-html-index.hbs b/app/assets/javascripts/admin/templates/customize-css-html-index.hbs
new file mode 100644
index 00000000000..781d063c7f2
--- /dev/null
+++ b/app/assets/javascripts/admin/templates/customize-css-html-index.hbs
@@ -0,0 +1 @@
+<p class="about">{{i18n 'admin.customize.about'}}</p>
diff --git a/app/assets/javascripts/admin/templates/customize-css-html-show.hbs b/app/assets/javascripts/admin/templates/customize-css-html-show.hbs
new file mode 100644
index 00000000000..4d93f5ee890
--- /dev/null
+++ b/app/assets/javascripts/admin/templates/customize-css-html-show.hbs
@@ -0,0 +1,74 @@
+<div class="current-style {{if maximized 'maximized'}}">
+  <div class='wrapper'>
+    {{text-field class="style-name" value=model.name}}
+    <a class="btn export" download target="_blank" href={{downloadUrl}}>{{fa-icon "download"}} {{i18n 'admin.export_json.button_text'}}</a>
+
+    <div class='admin-controls'>
+      <ul class="nav nav-pills">
+        {{#if mobile}}
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'mobile-css' replace=true}}{{i18n "admin.customize.css"}}{{/link-to}}</li>
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'mobile-header' replace=true}}{{i18n "admin.customize.header"}}{{/link-to}}</li>
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'mobile-top' replace=true}}{{i18n "admin.customize.top"}}{{/link-to}}</li>
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'mobile-footer' replace=true}}{{i18n "admin.customize.footer"}}{{/link-to}}</li>
+        {{else}}
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'css' replace=true}}{{i18n "admin.customize.css"}}{{/link-to}}</li>
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'header' replace=true}}{{i18n "admin.customize.header"}}{{/link-to}}</li>
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'top' replace=true}}{{i18n "admin.customize.top"}}{{/link-to}}</li>
+          <li>{{#link-to 'adminCustomizeCssHtml.show' model.id 'footer' replace=true}}{{i18n "admin.customize.footer"}}{{/link-to}}</li>
+          <li>
+            {{#link-to 'adminCustomizeCssHtml.show' model.id 'head-tag'}}
+              {{fa-icon "file-text-o"}}&nbsp;{{i18n 'admin.customize.head_tag.text'}}
+            {{/link-to}}
+          </li>
+          <li>
+            {{#link-to 'adminCustomizeCssHtml.show' model.id 'body-tag'}}
+              {{fa-icon "file-text-o"}}&nbsp;{{i18n 'admin.customize.body_tag.text'}}
+            {{/link-to}}
+          </li>
+        {{/if}}
+        <li class='toggle-mobile'>
+          <a {{bind-attr class="mobile:active"}} {{action "toggleMobile"}}>{{fa-icon "mobile"}}</a>
+        </li>
+        <li class='toggle-maximize'>
+          <a {{action "toggleMaximize"}}>
+            {{fa-icon-bound maximizeIcon}}
+          </a>
+        </li>
+      </ul>
+    </div>
+
+    <div class="admin-container">
+      {{#if cssActive}}{{ace-editor content=model.stylesheet mode="scss"}}{{/if}}
+      {{#if headerActive}}{{ace-editor content=model.header mode="html"}}{{/if}}
+      {{#if topActive}}{{ace-editor content=model.top mode="html"}}{{/if}}
+      {{#if footerActive}}{{ace-editor content=model.footer mode="html"}}{{/if}}
+      {{#if headTagActive}}{{ace-editor content=model.head_tag mode="html"}}{{/if}}
+      {{#if bodyTagActive}}{{ace-editor content=model.body_tag mode="html"}}{{/if}}
+      {{#if mobileCssActive}}{{ace-editor content=model.mobile_stylesheet mode="scss"}}{{/if}}
+      {{#if mobileHeaderActive}}{{ace-editor content=model.mobile_header mode="html"}}{{/if}}
+      {{#if mobileTopActive}}{{ace-editor content=model.mobile_top mode="html"}}{{/if}}
+      {{#if mobileFooterActive}}{{ace-editor content=model.mobile_footer mode="html"}}{{/if}}
+    </div>
+
+    <div class='admin-footer'>
+      <div class='status-actions'>
+        <span>{{i18n 'admin.customize.enabled'}} {{input type="checkbox" checked=model.enabled}}</span>
+        {{#unless model.changed}}
+          <a class='preview-link' href={{previewUrl}} target='_blank' title="{{i18n 'admin.customize.explain_preview'}}">{{i18n 'admin.customize.preview'}}</a>
+          |
+          <a href={{undoPreviewUrl}} target='_blank' title="{{i18n 'admin.customize.explain_undo_preview'}}">{{i18n 'admin.customize.undo_preview'}}</a>
+          |
+          <a href={{defaultStyleUrl}} target='_blank' title="{{i18n 'admin.customize.explain_rescue_preview'}}">{{i18n 'admin.customize.rescue_preview'}}</a><br>
+        {{/unless}}
+      </div>
+
+      <div class='buttons'>
+        {{#d-button action="save" disabled=saveDisabled class='btn-primary'}}
+          {{saveButtonText}}
+        {{/d-button}}
+        {{d-button action="destroy" label="admin.customize.delete" icon="trash" class="btn-danger"}}
+      </div>
+    </div>
+  </div>
+</div>
+
diff --git a/app/assets/javascripts/admin/templates/customize-css-html.hbs b/app/assets/javascripts/admin/templates/customize-css-html.hbs
new file mode 100644
index 00000000000..73b8e22c9f2
--- /dev/null
+++ b/app/assets/javascripts/admin/templates/customize-css-html.hbs
@@ -0,0 +1,13 @@
+<div class='content-list span6'>
+  <h3>{{i18n 'admin.customize.css_html.long_title'}}</h3>
+  <ul>
+    {{#each model as |c|}}
+      {{customize-link customization=c}}
+    {{/each}}
+  </ul>
+
+  {{d-button label="admin.customize.new" icon="plus" action="newCustomization" class="btn-primary"}}
+  {{d-button action="importModal" icon="upload" label="admin.customize.import"}}
+</div>
+
+{{outlet}}
diff --git a/app/assets/javascripts/admin/templates/customize.hbs b/app/assets/javascripts/admin/templates/customize.hbs
index c009909e1a7..130b75e0ac6 100644
--- a/app/assets/javascripts/admin/templates/customize.hbs
+++ b/app/assets/javascripts/admin/templates/customize.hbs
@@ -1,6 +1,6 @@
 {{#admin-nav}}
   {{nav-item route='adminCustomize.colors' label='admin.customize.colors.title'}}
-  {{nav-item route='adminCustomize.css_html' label='admin.customize.css_html.title'}}
+  {{nav-item route='adminCustomizeCssHtml.index' label='admin.customize.css_html.title'}}
   {{nav-item route='adminSiteText' label='admin.site_text.title'}}
   {{nav-item route='adminUserFields' label='admin.user_fields.title'}}
   {{nav-item route='adminEmojis' label='admin.emoji.title'}}
diff --git a/app/assets/javascripts/admin/templates/customize_css_html.hbs b/app/assets/javascripts/admin/templates/customize_css_html.hbs
deleted file mode 100644
index f4dce62b091..00000000000
--- a/app/assets/javascripts/admin/templates/customize_css_html.hbs
+++ /dev/null
@@ -1,84 +0,0 @@
-<div class='content-list span6'>
-  <h3>{{i18n 'admin.customize.css_html.long_title'}}</h3>
-  <ul>
-    {{#each style in model}}
-      <li><a {{action "selectStyle" style}} {{bind-attr class="style.selected:active"}}>{{style.description}}</a></li>
-    {{/each}}
-  </ul>
-  <button {{action "newCustomization"}} class='btn'>
-    {{fa-icon "plus"}}{{i18n 'admin.customize.new'}}
-  </button>
-  {{d-button action="importModal" icon="upload" label="admin.customize.import"}}
-</div>
-
-{{#if selectedItem}}
-  <div {{bind-attr class=":current-style view.maximized:maximized"}}>
-    <div class='wrapper'>
-      {{text-field class="style-name" value=selectedItem.name}}
-      <a class="btn export" download target="_blank" href={{selectedItem.download_url}}>{{fa-icon "download"}} {{i18n 'admin.export_json.button_text'}}</a>
-
-      <div class='admin-controls'>
-        <ul class="nav nav-pills">
-          {{#if view.mobile}}
-            <li><a {{bind-attr class="view.mobileStylesheetActive:active"}} {{action "select" "mobile_stylesheet" target="view"}}>{{fa-icon "mobile"}}&nbsp;{{i18n 'admin.customize.css'}}</a></li>
-            <li><a {{bind-attr class="view.mobileHeaderActive:active"}} {{action "select" "mobile_header" target="view"}}>{{fa-icon "mobile"}}&nbsp;{{i18n 'admin.customize.header'}}</a></li>
-            <li><a {{bind-attr class="view.mobileTopActive:active"}} {{action "select" "mobile_top" target="view"}}>{{fa-icon "mobile"}}&nbsp;{{i18n 'admin.customize.top'}}</a></li>
-            <li><a {{bind-attr class="view.mobileFooterActive:active"}} {{action "select" "mobile_footer" target="view"}}>{{fa-icon "mobile"}}&nbsp;{{i18n 'admin.customize.footer'}}</a></li>
-          {{else}}
-            <li><a {{bind-attr class="view.stylesheetActive:active"}} {{action "select" "stylesheet" target="view"}}>{{i18n 'admin.customize.css'}}</a></li>
-            <li><a {{bind-attr class="view.headerActive:active"}} {{action "select" "header" target="view"}}>{{i18n 'admin.customize.header'}}</a></li>
-            <li><a {{bind-attr class="view.topActive:active"}} {{action "select" "top" target="view"}}>{{i18n 'admin.customize.top'}}</a></li>
-            <li><a {{bind-attr class="view.footerActive:active"}} {{action "select" "footer" target="view"}}>{{i18n 'admin.customize.footer'}}</a></li>
-            <li><a {{bind-attr class="view.headTagActive:active"}} {{action "select" "head_tag" target="view"}} title="{{i18n 'admin.customize.head_tag.title'}}">{{fa-icon "file-text-o"}}&nbsp;{{i18n 'admin.customize.head_tag.text'}}</a></li>
-            <li><a {{bind-attr class="view.bodyTagActive:active"}} {{action "select" "body_tag" target="view"}} title="{{i18n 'admin.customize.body_tag.title'}}">{{fa-icon "file-text-o"}}&nbsp;{{i18n 'admin.customize.body_tag.text'}}</a></li>
-          {{/if}}
-          <li class='toggle-mobile'>
-            <a {{bind-attr class="view.mobile:active"}} {{action "toggleMobile" target="view"}}>{{fa-icon "mobile"}}</a>
-          </li>
-          <li class='toggle-maximize'>
-            <a {{action "toggleMaximize" target="view"}}>
-              {{#if view.maximized}}
-                {{fa-icon "compress"}}
-              {{else}}
-                {{fa-icon "expand"}}
-              {{/if}}
-            </a>
-          </li>
-        </ul>
-      </div>
-
-      <div class="admin-container">
-        {{#if view.stylesheetActive}}{{ace-editor content=selectedItem.stylesheet mode="scss"}}{{/if}}
-        {{#if view.headerActive}}{{ace-editor content=selectedItem.header mode="html"}}{{/if}}
-        {{#if view.topActive}}{{ace-editor content=selectedItem.top mode="html"}}{{/if}}
-        {{#if view.footerActive}}{{ace-editor content=selectedItem.footer mode="html"}}{{/if}}
-        {{#if view.headTagActive}}{{ace-editor content=selectedItem.head_tag mode="html"}}{{/if}}
-        {{#if view.bodyTagActive}}{{ace-editor content=selectedItem.body_tag mode="html"}}{{/if}}
-        {{#if view.mobileStylesheetActive}}{{ace-editor content=selectedItem.mobile_stylesheet mode="scss"}}{{/if}}
-        {{#if view.mobileHeaderActive}}{{ace-editor content=selectedItem.mobile_header mode="html"}}{{/if}}
-        {{#if view.mobileTopActive}}{{ace-editor content=selectedItem.mobile_top mode="html"}}{{/if}}
-        {{#if view.mobileFooterActive}}{{ace-editor content=selectedItem.mobile_footer mode="html"}}{{/if}}
-      </div>
-      <div class='admin-footer'>
-        <div class='status-actions'>
-          <span>{{i18n 'admin.customize.enabled'}} {{input type="checkbox" checked=selectedItem.enabled}}</span>
-          {{#unless selectedItem.changed}}
-          <a class='preview-link' {{bind-attr href="selectedItem.previewUrl"}} target='_blank' title="{{i18n 'admin.customize.explain_preview'}}">{{i18n 'admin.customize.preview'}}</a>
-          |
-          <a href="{{undoPreviewUrl}}" target='_blank' title="{{i18n 'admin.customize.explain_undo_preview'}}">{{i18n 'admin.customize.undo_preview'}}</a>
-          |
-          <a href="{{defaultStyleUrl}}" target='_blank' title="{{i18n 'admin.customize.explain_rescue_preview'}}">{{i18n 'admin.customize.rescue_preview'}}</a><br>
-          {{/unless}}
-        </div>
-
-        <div class='buttons'>
-          <button {{action "save"}} {{bind-attr disabled="selectedItem.disableSave"}} class='btn'>{{i18n 'admin.customize.save'}}</button>
-          <span class='saving'>{{selectedItem.savingStatus}}</span>
-          <a {{action "destroy"}} class='delete-link'>{{i18n 'admin.customize.delete'}}</a>
-        </div>
-      </div>
-    </div>
-  </div>
-{{else}}
-  <p class="about">{{i18n 'admin.customize.about'}}</p>
-{{/if}}
diff --git a/app/assets/javascripts/admin/views/admin-customize.js.es6 b/app/assets/javascripts/admin/views/admin-customize.js.es6
new file mode 100644
index 00000000000..faca47026f6
--- /dev/null
+++ b/app/assets/javascripts/admin/views/admin-customize.js.es6
@@ -0,0 +1,18 @@
+/*global Mousetrap:true */
+
+export default Ember.View.extend({
+  classNames: ['customize'],
+
+  _init: function() {
+    var controller = this.get('controller');
+    Mousetrap.bindGlobal('mod+s', function() {
+      controller.send("save");
+      return false;
+    });
+  }.on("didInsertElement"),
+
+  _cleanUp: function() {
+    Mousetrap.unbindGlobal('mod+s');
+  }.on("willDestroyElement")
+
+});
diff --git a/app/assets/javascripts/admin/views/admin_customize_view.js b/app/assets/javascripts/admin/views/admin_customize_view.js
deleted file mode 100644
index 37ecfaceb1d..00000000000
--- a/app/assets/javascripts/admin/views/admin_customize_view.js
+++ /dev/null
@@ -1,68 +0,0 @@
-/*global Mousetrap:true */
-
-/**
-  A view to handle site customizations
-
-  @class AdminCustomizeView
-  @extends Discourse.View
-  @namespace Discourse
-  @module Discourse
-**/
-Discourse.AdminCustomizeView = Discourse.View.extend({
-  templateName: 'admin/templates/customize',
-  classNames: ['customize'],
-  selected: 'stylesheet',
-  mobile: false,
-
-  stylesheetActive:       Em.computed.equal('selected', 'stylesheet'),
-  headerActive:           Em.computed.equal('selected', 'header'),
-  topActive:              Em.computed.equal('selected', 'top'),
-  footerActive:           Em.computed.equal('selected', 'footer'),
-  headTagActive:          Em.computed.equal('selected', 'head_tag'),
-  bodyTagActive:          Em.computed.equal('selected', 'body_tag'),
-
-  mobileStylesheetActive: Em.computed.equal('selected', 'mobile_stylesheet'),
-  mobileHeaderActive:     Em.computed.equal('selected', 'mobile_header'),
-  mobileTopActive:        Em.computed.equal('selected', 'mobile_top'),
-  mobileFooterActive:     Em.computed.equal('selected', 'mobile_footer'),
-
-  actions: {
-    toggleMobile: function() {
-      // auto-select best tab
-      var tab = this.get("selected");
-      if (/_tag$/.test(tab)) { tab = "stylesheet"; }
-      if (this.get("mobile")) { tab = tab.replace("mobile_", ""); }
-      else { tab = "mobile_" + tab; }
-      this.set("selected", tab);
-      // toggle mobile
-      this.toggleProperty("mobile");
-    },
-
-    select: function(tab) {
-      this.set('selected', tab);
-    },
-
-    toggleMaximize: function() {
-      this.set("maximized", !this.get("maximized"));
-
-      Em.run.scheduleOnce('afterRender', this, function(){
-        $('.ace-wrapper').each(function(){
-          $(this).data("editor").resize();
-        });
-      });
-    },
-  },
-
-  _init: function() {
-    var controller = this.get('controller');
-    Mousetrap.bindGlobal('mod+s', function() {
-      controller.send("save");
-      return false;
-    });
-  }.on("didInsertElement"),
-
-  _cleanUp: function() {
-    Mousetrap.unbindGlobal('mod+s');
-  }.on("willDestroyElement")
-
-});
diff --git a/app/assets/javascripts/discourse/adapters/rest.js.es6 b/app/assets/javascripts/discourse/adapters/rest.js.es6
index 5a64730aba1..5e427a86589 100644
--- a/app/assets/javascripts/discourse/adapters/rest.js.es6
+++ b/app/assets/javascripts/discourse/adapters/rest.js.es6
@@ -1,4 +1,4 @@
-const ADMIN_MODELS = ['plugin'];
+const ADMIN_MODELS = ['plugin', 'site-customization'];
 
 export function Result(payload, responseJson) {
   this.payload = payload;
diff --git a/app/assets/javascripts/discourse/controllers/upload-customization.js.es6 b/app/assets/javascripts/discourse/controllers/upload-customization.js.es6
index 09158f53752..72bf3aee6ee 100644
--- a/app/assets/javascripts/discourse/controllers/upload-customization.js.es6
+++ b/app/assets/javascripts/discourse/controllers/upload-customization.js.es6
@@ -2,20 +2,15 @@ import ModalFunctionality from 'discourse/mixins/modal-functionality';
 
 export default Ember.Controller.extend(ModalFunctionality, {
   notReady: Em.computed.not('ready'),
-
-  needs: ['admin-customize-css-html'],
-
-  title: "hi",
+  needs: ['adminCustomizeCssHtml'],
 
   ready: function() {
-    let parsed;
     try {
-      parsed = JSON.parse(this.get('customizationFile'));
+      const parsed = JSON.parse(this.get('customizationFile'));
+      return !!parsed["site_customization"];
     } catch (e) {
       return false;
     }
-
-    return !!parsed["site_customization"];
   }.property('customizationFile'),
 
   actions: {
@@ -28,24 +23,8 @@ export default Ember.Controller.extend(ModalFunctionality, {
       delete object.id;
       delete object.key;
 
-      const customization = Discourse.SiteCustomization.create(object);
-
-      this.set('loading', true);
-      customization.save().then(function(customization) {
-        self.send('closeModal');
-        self.set('loading', false);
-
-        const parentController = self.get('controllers.admin-customize-css-html');
-        parentController.pushObject(customization);
-        parentController.set('selectedItem', customization);
-      }).catch(function(xhr) {
-        self.set('loading', false);
-        if (xhr.responseJSON) {
-          bootbox.alert(xhr.responseJSON.errors.join("<br>"));
-        } else {
-          bootbox.alert(I18n.t('generic_error'));
-        }
-      });
+      const controller = this.get('controllers.adminCustomizeCssHtml');
+      controller.send('newCustomization', object);
     }
   }
 
diff --git a/app/assets/javascripts/discourse/helpers/fa-icon.js.es6 b/app/assets/javascripts/discourse/helpers/fa-icon.js.es6
index e979ebab90e..456f876054f 100644
--- a/app/assets/javascripts/discourse/helpers/fa-icon.js.es6
+++ b/app/assets/javascripts/discourse/helpers/fa-icon.js.es6
@@ -19,6 +19,9 @@ function iconHTML(icon, params) {
   return html;
 }
 
+Ember.Handlebars.helper('fa-icon-bound', function(value, options) {
+  return new Handlebars.SafeString(iconHTML(value, options));
+});
 
 registerUnbound('fa-icon', function(icon, params) {
   return new Handlebars.SafeString(iconHTML(icon, params));
diff --git a/app/assets/javascripts/discourse/models/store.js.es6 b/app/assets/javascripts/discourse/models/store.js.es6
index cda112cefb6..a9aa86f294e 100644
--- a/app/assets/javascripts/discourse/models/store.js.es6
+++ b/app/assets/javascripts/discourse/models/store.js.es6
@@ -116,6 +116,12 @@ export default Ember.Object.extend({
   },
 
   destroyRecord(type, record) {
+    // If the record is new, don't perform an Ajax call
+    if (record.get('isNew')) {
+      removeMap(type, record.get('id'));
+      return Ember.RSVP.Promise.resolve(true);
+    }
+
     return this.adapterFor(type).destroyRecord(this, type, record).then(function(result) {
       removeMap(type, record.get('id'));
       return result;
diff --git a/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs b/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs
index 6d5d53e5bbf..db8cf3de279 100644
--- a/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs
+++ b/app/assets/javascripts/discourse/templates/modal/upload-customization.hbs
@@ -1,4 +1,4 @@
-<form {{action "dummy" on="submit"}}>
+<form>
   <div class='modal-body'>
     {{json-file-uploader value=customizationFile extension=".dcstyle.json"}}
   </div>
diff --git a/app/controllers/admin/site_customizations_controller.rb b/app/controllers/admin/site_customizations_controller.rb
index 30929fe4e09..0308b85b96b 100644
--- a/app/controllers/admin/site_customizations_controller.rb
+++ b/app/controllers/admin/site_customizations_controller.rb
@@ -32,7 +32,7 @@ class Admin::SiteCustomizationsController < Admin::AdminController
 
     respond_to do |format|
       if @site_customization.update_attributes(site_customization_params)
-        format.json { head :no_content }
+        format.json { render json: @site_customization, status: :created}
       else
         log_record.destroy if log_record
         format.json { render json: @site_customization.errors, status: :unprocessable_entity }
diff --git a/config/routes.rb b/config/routes.rb
index 98fc8396234..30f7aa34c38 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -132,6 +132,7 @@ Discourse::Application.routes.draw do
 
     get "customize" => "color_schemes#index", constraints: AdminConstraint.new
     get "customize/css_html" => "site_customizations#index", constraints: AdminConstraint.new
+    get "customize/css_html/:id/:section" => "site_customizations#index", constraints: AdminConstraint.new
     get "customize/colors" => "color_schemes#index", constraints: AdminConstraint.new
     get "customize/permalinks" => "permalinks#index", constraints: AdminConstraint.new
     get "flags" => "flags#index"
diff --git a/test/javascripts/models/store-test.js.es6 b/test/javascripts/models/store-test.js.es6
index bac22ecd5a6..46585ce6820 100644
--- a/test/javascripts/models/store-test.js.es6
+++ b/test/javascripts/models/store-test.js.es6
@@ -97,6 +97,15 @@ test('destroyRecord', function(assert) {
   });
 });
 
+test('destroyRecord when new', function(assert) {
+  const store = createStore();
+  const w = store.createRecord('widget', {name: 'hello'});
+  store.destroyRecord('widget', w).then(function(result) {
+    assert.ok(result);
+  });
+});
+
+
 test('find embedded', function() {
   const store = createStore();
   return store.find('fruit', 1).then(function(f) {