diff --git a/web/react/components/user_settings/manage_incoming_hooks.jsx b/web/react/components/user_settings/manage_incoming_hooks.jsx
index 12c041c7f4..1bbfbd162a 100644
--- a/web/react/components/user_settings/manage_incoming_hooks.jsx
+++ b/web/react/components/user_settings/manage_incoming_hooks.jsx
@@ -134,7 +134,7 @@ export default class ManageIncomingHooks extends React.Component {
         } else if (hooks.length > 0) {
             displayHooks = hooks;
         } else {
-            displayHooks = <label>{' None'}</label>;
+            displayHooks = <label>{': None'}</label>;
         }
 
         const existingHooks = (
diff --git a/web/react/utils/constants.jsx b/web/react/utils/constants.jsx
index 8c9e1ee85f..0650fb92b7 100644
--- a/web/react/utils/constants.jsx
+++ b/web/react/utils/constants.jsx
@@ -130,6 +130,7 @@ module.exports = {
             mentionColor: '#ffffff',
             centerChannelBg: '#ffffff',
             centerChannelColor: '#333333',
+            newMessageSeparator: '#FF8800',
             linkColor: '#2389d7',
             buttonBg: '#2389d7',
             buttonColor: '#FFFFFF'
@@ -150,12 +151,13 @@ module.exports = {
             mentionColor: '#bfcde8',
             centerChannelBg: '#f2f4f8',
             centerChannelColor: '#333333',
+            newMessageSeparator: '#FF8800',
             linkColor: '#2f81b7',
             buttonBg: '#1dacfc',
             buttonColor: '#FFFFFF'
         },
-        dark: {
-            type: 'Dark',
+        mattermostDark: {
+            type: 'Mattermost Dark',
             sidebarBg: '#1B2C3E',
             sidebarText: '#bbbbbb',
             sidebarUnreadText: '#fff',
@@ -170,9 +172,31 @@ module.exports = {
             mentionColor: '#FFFFFF',
             centerChannelBg: '#2F3E4E',
             centerChannelColor: '#DDDDDD',
+            newMessageSeparator: '#5de5da',
             linkColor: '#A4FFEB',
             buttonBg: '#1dacfc',
             buttonColor: '#FFFFFF'
+        },
+        windows10: {
+            type: 'Windows 10 Dark',
+            sidebarBg: '#171717',
+            sidebarText: '#eee',
+            sidebarUnreadText: '#fff',
+            sidebarTextHoverBg: '#302e30',
+            sidebarTextHoverColor: '#fff',
+            sidebarTextActiveBg: '#484748',
+            sidebarTextActiveColor: '#FFFFFF',
+            sidebarHeaderBg: '#1f1f1f',
+            sidebarHeaderTextColor: '#FFFFFF',
+            onlineIndicator: '#0177e7',
+            mentionBj: '#0177e7',
+            mentionColor: '#FFFFFF',
+            centerChannelBg: '#1F1F1F',
+            centerChannelColor: '#DDDDDD',
+            newMessageSeparator: '#CC992D',
+            linkColor: '#0177e7',
+            buttonBg: '#0177e7',
+            buttonColor: '#FFFFFF'
         }
     },
     THEME_ELEMENTS: [
@@ -232,6 +256,10 @@ module.exports = {
             id: 'centerChannelColor',
             uiName: 'Center Channel Text'
         },
+        {
+            id: 'newMessageSeparator',
+            uiName: 'New message separator'
+        },
         {
             id: 'linkColor',
             uiName: 'Link Color'
diff --git a/web/react/utils/utils.jsx b/web/react/utils/utils.jsx
index d45240f9a4..280370c337 100644
--- a/web/react/utils/utils.jsx
+++ b/web/react/utils/utils.jsx
@@ -615,7 +615,7 @@ export function applyTheme(theme) {
     }
 
     if (theme.centerChannelColor) {
-        changeCss('.app__content, .post-create__container .post-create-body .btn-file', 'color:' + theme.centerChannelColor, 1);
+        changeCss('.app__content, .post-create__container .post-create-body .btn-file, .post-create__container .post-create-footer .msg-typing, .loading-screen .loading__content .round', 'color:' + theme.centerChannelColor, 1);
         changeCss('#post-create', 'color:' + theme.centerChannelColor, 2);
         changeCss('.post-body hr', 'background:' + theme.centerChannelColor, 1);
         changeCss('.channel-header .heading', 'color:' + theme.centerChannelColor, 1);
@@ -630,8 +630,8 @@ export function applyTheme(theme) {
         changeCss('.search-bar__container .search__form .search-bar', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2) + '; color: ' + theme.centerChannelColor, 2);
         changeCss('.search-bar__container .search__form', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
         changeCss('.channel-intro .channel-intro__content', 'background:' + changeOpacity(theme.centerChannelColor, 0.05), 1);
-        changeCss('.date-separator .separator__text, .new-separator .separator__text', 'color:' + theme.centerChannelColor, 2);
-        changeCss('.date-separator .separator__hr, .new-separator .separator__hr, .post-right__container .post.post--root hr, .search-item-container', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
+        changeCss('.date-separator .separator__text', 'color:' + theme.centerChannelColor, 2);
+        changeCss('.date-separator .separator__hr, .post-right__container .post.post--root hr, .search-item-container', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
         changeCss('.channel-intro', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
         changeCss('.post.current--user .post-body, .post.post--comment.other--root.current--user .post-comment', 'background:' + changeOpacity(theme.centerChannelColor, 0.07), 1);
         changeCss('.post.current--user .post-body, .post.post--comment.other--root.current--user .post-comment, .post.post--comment.other--root .post-comment, .post.same--root .post-body', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.07), 2);
@@ -645,6 +645,11 @@ export function applyTheme(theme) {
         changeCss('.sidebar--right', 'color:' + theme.centerChannelColor, 2);
     }
 
+    if (theme.newMessageSeparator) {
+        changeCss('.new-separator .separator__text', 'color:' + theme.newMessageSeparator, 1);
+        changeCss('.new-separator .separator__hr', 'border-color:' + changeOpacity(theme.newMessageSeparator, 0.5), 1);
+    }
+
     if (theme.linkColor) {
         changeCss('a, a:focus, a:hover', 'color:' + theme.linkColor, 1);
         changeCss('.post .comment-icon__container', 'fill:' + theme.linkColor, 1);
diff --git a/web/sass-files/sass/partials/_loading.scss b/web/sass-files/sass/partials/_loading.scss
index d710557224..ab8601df6b 100644
--- a/web/sass-files/sass/partials/_loading.scss
+++ b/web/sass-files/sass/partials/_loading.scss
@@ -37,4 +37,4 @@
 			to { opacity: 0.1; }
 		}
 	}
-}
+}
\ No newline at end of file
diff --git a/web/sass-files/sass/partials/_post.scss b/web/sass-files/sass/partials/_post.scss
index a1958af3b9..7532875d64 100644
--- a/web/sass-files/sass/partials/_post.scss
+++ b/web/sass-files/sass/partials/_post.scss
@@ -185,7 +185,7 @@ body.ios {
 .post-create__container {
 	form {
 		width: 100%;
-		padding: 10px 1em 0 1em;
+		padding: 0 1em;
 		margin: 0;
 	}
 	.post-create-body {
@@ -257,7 +257,7 @@ body.ios {
 			line-height: 18px;
 			display: inline-block;
 			font-size: 13px;
-			color: #777;
+			@include opacity(0.6);
 		}
 	}
 }
diff --git a/web/sass-files/sass/partials/_responsive.scss b/web/sass-files/sass/partials/_responsive.scss
index e0b35d0bfa..d29c653ffe 100644
--- a/web/sass-files/sass/partials/_responsive.scss
+++ b/web/sass-files/sass/partials/_responsive.scss
@@ -417,7 +417,7 @@
             padding: 0 1em;
         }
         form {
-            padding: 10px 0 0 0;
+            padding: 0;
         }
         .post-create-body {
             padding-bottom: 10px;
diff --git a/web/static/images/themes/dark.png b/web/static/images/themes/mattermost dark.png
similarity index 100%
rename from web/static/images/themes/dark.png
rename to web/static/images/themes/mattermost dark.png
diff --git a/web/static/images/themes/windows 10 dark.png b/web/static/images/themes/windows 10 dark.png
new file mode 100644
index 0000000000..d653048209
Binary files /dev/null and b/web/static/images/themes/windows 10 dark.png differ