diff --git a/skins/kolab/README.md b/skins/kolab/README.md
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+Roundcube Webmail Skin "Kolab Elastic"
+======================================
+
+This skin package contains modifications of the Roundcube's Elastic skin.
+It can be used, modified and redistributed according to
+the terms described in the LICENSE section.
+
+For information about building or modifying Roundcube skins please visit
+https://github.com/roundcube/roundcubemail/wiki/Skins
+
+
+LICENSE
+-------
+
+The contents of this folder can be redistributed and/or modified
+under the terms of the GNU Affero General Public License as published
+by the Free Software Foundation, either version 3 of the License,
+or (at your option) any later version.
+
+
+INSTALLATION
+------------
+
+All styles are written using LESS syntax. Thus it needs to be compiled
+using the `lessc` command line tool. This comes with the `nodejs-less`
+RPM package which depends on nodejs.
+
+First create a skin folder in the Roundcube skins directory as a copy
+of the Elastic skin:
+
+```
+ $ cp -r roundcubemail/skins/elastic roundcubemail/skins/kolab
+ $ cp -r roundcubemail-skin-elastic/kolab/* roundcubemail/skins/kolab
+```
+
+Then you can compile css of the skin in a usual way:
+
+```
+ $ cd roundcubemail/skins/kolab
+ $ lessc -x styles/styles.less > styles/styles.css
+ $ lessc -x styles/print.less > styles/print.css
+ $ lessc -x styles/embed.less > styles/embed.css
+```
+
+Css for external plugins need to be rebuild too, e.g. Kolab plugins.
+
+```
+ $ cd roundcubemail-plugins-kolab/plugins/libkolab
+ $ cp -r skins/elastic skins/kolab
+ $ sed -i 's/"elastic"/"kolab"/g' skins/kolab/libkolab.less
+ $ lessc --relative-urls -x skins/kolab/libkolab.less > skins/kolab/styles.css
+```
+
+References to image files from the included CSS files can be appended
+with cache-buster marks to avoid browser caching issues after updating.
+
+Run `bin/updatecss.sh --dir skins/kolab` before packaging the skin
+or after installing it on the destination system.
diff --git a/skins/kolab/images/favicon.ico b/skins/kolab/images/favicon.ico
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diff --git a/skins/kolab/images/logo.svg b/skins/kolab/images/logo.svg
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+
+
diff --git a/skins/kolab/images/watermark.svg b/skins/kolab/images/watermark.svg
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+
+
diff --git a/skins/kolab/meta.json b/skins/kolab/meta.json
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+{
+ "name": "Kolab (Responsive Version)",
+ "author": "Kolab Systems AG, Zurich, Switzerland",
+ "license": "GNU Affero General Public License",
+ "license-url": "http://www.gnu.org/licenses/agpl.html",
+ "extends": "elastic",
+ "config": {
+ "pwa_theme_color": "#3a444e",
+ "pwa_tile_color": "#3a444e",
+ "pwa_pinned_tab_color": "#f4c200",
+ "pwa_name": "Kolab Groupware",
+ "pwa_short_name": "Kolab",
+ "pwa_description": "Free and Open Source Groupware Server"
+ }
+}
diff --git a/skins/kolab/pwa/android-chrome-192x192.png b/skins/kolab/pwa/android-chrome-192x192.png
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diff --git a/skins/kolab/pwa/android-chrome-512x512.png b/skins/kolab/pwa/android-chrome-512x512.png
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diff --git a/skins/kolab/pwa/apple-touch-icon.png b/skins/kolab/pwa/apple-touch-icon.png
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diff --git a/skins/kolab/pwa/favicon-16x16.png b/skins/kolab/pwa/favicon-16x16.png
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diff --git a/skins/kolab/pwa/favicon-32x32.png b/skins/kolab/pwa/favicon-32x32.png
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diff --git a/skins/kolab/pwa/favicon.ico b/skins/kolab/pwa/favicon.ico
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diff --git a/skins/kolab/pwa/safari-pinned-tab.svg b/skins/kolab/pwa/safari-pinned-tab.svg
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+++ b/skins/kolab/pwa/safari-pinned-tab.svg
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+
+
+
diff --git a/skins/kolab/styles/_styles.less b/skins/kolab/styles/_styles.less
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+/**
+ * Styles for the Kolab web client variant of the Roundcube Elastic skin
+ *
+ * Copyright (C) 2018, Kolab Systems AG
+ *
+ * The contents of this folder can be redistributed and/or modified
+ * under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License,
+ * or (at your option) any later version.
+ */
+
+// Modify taskmenu behavior
+#taskmenu {
+ span.inner {
+ text-transform: uppercase;
+ }
+
+ @media screen and (min-width: (@screen-width-medium + 1px)) and (min-height: 640px) {
+ span.inner {
+ font-size: 65%;
+ font-weight: bold;
+ }
+
+ a:before {
+ line-height: 1.2;
+ font-size: 180%;
+ height: 1.9rem !important;
+ }
+ }
+
+ @media screen and (min-width: (@screen-width-small + 1px)) {
+ a.logout:not(:hover) {
+ color: @color-taskmenu-button !important;
+ }
+ }
+
+ .action-buttons {
+ display: none;
+ }
+}
+
+// Fix mobile menu header background
+#layout-menu .popover-header {
+ background-color: @color-taskmenu-background !important;
+
+ img {
+ width: 100%;
+
+ html.layout-phone & {
+ width: unset;
+ max-height: @layout-header-height;
+ }
+ }
+}
+
+.watermark {
+ background-image: url(../images/watermark.svg) !important;
+ background-size: 60% !important;
+ background-blend-mode: unset !important;
+
+ &:before {
+ background: rgba(255, 255, 255, 0.75) !important;
+ }
+}
+
+// Display the Compose button in mail toolbar
+body.task-mail .menu a.compose {
+ display: block !important;
+}
+
+// Move the contact photo in mail preview to the right
+#message-header .short-header img.contactphoto {
+ order: 2;
+ margin: 0 0 0 1rem;
+}
+
+// Make the content frame navigation smaller
+.content-frame-navigation {
+ height: @layout-footer-small-height !important;
+ line-height: @layout-footer-small-height !important;
+ min-height: @layout-footer-small-height !important;
+
+ a {
+ max-width: 8em;
+ padding: 0;
+ line-height: @layout-footer-small-height;
+
+ &:before {
+ display: none !important;
+ height: @layout-footer-small-height !important;
+ line-height: @layout-footer-small-height !important;
+ }
+
+ &.prev,
+ &.next {
+ padding: 0;
+
+ &:before {
+ display: block !important;
+ line-height: 1.8;
+ }
+
+ span.inner {
+ display: none;
+ }
+ }
+
+ span.inner {
+ color: @color-link;
+ font-weight: bold;
+ }
+ }
+}
diff --git a/skins/kolab/styles/_variables.less b/skins/kolab/styles/_variables.less
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+/**
+ * Styles for the Kolab web client variant of the Roundcube Elastic skin
+ *
+ * Copyright (C) 2018, Kolab Systems AG
+ *
+ * The contents of this folder can be redistributed and/or modified
+ * under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License,
+ * or (at your option) any later version.
+ */
+
+@color-main: #f4c200;
+@color-font: #4f4f4f;
+@color-main-dark: darken(@color-main, 30%);
+@color-link: @color-main;
+
+@color-black-shade-bg: #f8f7f4;
+@color-black-shade-text: #7b7b77;
+
+@color-layout-header-background: #f1eeea;
+@color-layout-border: #d4dbde;
+
+
+@color-taskmenu-background: #3a444e;
+@color-taskmenu-button: #71777d;
+@color-taskmenu-button-hover: #e1e2e3;
+@color-taskmenu-button-selected: #e1e2e3;
+
+@color-popover-mobile-header-background: @color-taskmenu-background;
+
+@color-toolbar-button: #7b7b77;
+@color-toolbar-button-background-hover: tint(@color-layout-header-background, 40%);
+
+@color-list-selected-background: tint(@color-main, 85%);
diff --git a/skins/kolab/watermark.html b/skins/kolab/watermark.html
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+
+
+
+
+
+
+
+