diff --git a/.gitignore b/.gitignore
index ac29bb403c..feb702cb86 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,6 +17,7 @@
 /phpBB/styles/*
 !/phpBB/styles/prosilver
 !/phpBB/styles/all
+/phpBB/node_modules
 /phpBB/vendor
 /tests/phpbb_unit_tests.sqlite*
 /tests/test_config*.php
diff --git a/.travis.yml b/.travis.yml
index 19251d6155..bdcc354641 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -31,6 +31,11 @@ matrix:
     - php: nightly
   fast_finish: true
 
+addons:
+  apt:
+    sources:
+      - node
+
 services:
   - redis-server
 
@@ -46,6 +51,7 @@ script:
   - travis/check-sami-parse-errors.sh $DB $TRAVIS_PHP_VERSION $NOTESTS
   - travis/check-image-icc-profiles.sh $DB $TRAVIS_PHP_VERSION $NOTESTS
   - travis/check-executable-files.sh $DB $TRAVIS_PHP_VERSION $NOTESTS ./
+  - travis/check-stylesheet.sh $NOTESTS
   - sh -c "if [ '$SLOWTESTS' != '1' -a '$DB' = 'mysqli' ]; then phpBB/vendor/bin/phpunit tests/lint_test.php; fi"
   - sh -c "if [ '$NOTESTS' != '1' -a '$SLOWTESTS' != '1' ]; then phpBB/vendor/bin/phpunit --configuration travis/phpunit-$DB-travis.xml; fi"
   - sh -c "if [ '$SLOWTESTS' = '1' ]; then phpBB/vendor/bin/phpunit --configuration travis/phpunit-$DB-travis.xml --group slow; fi"
diff --git a/phpBB/package.json b/phpBB/package.json
new file mode 100644
index 0000000000..fc85b20a99
--- /dev/null
+++ b/phpBB/package.json
@@ -0,0 +1,34 @@
+{
+  "name": "phpbb",
+  "version": "3.3.0-dev",
+  "description": "phpBB Forum Software application",
+  "main": " ",
+  "directories": {
+    "doc": "docs"
+  },
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/phpbb/phpbb.git"
+  },
+  "keywords": [
+    "phpBB",
+    "phpbb",
+    "forum",
+    "php",
+    "software",
+    "community"
+  ],
+  "author": "",
+  "license": "GPL-2.0",
+  "bugs": {
+    "url": "https://tracker.phpbb.com"
+  },
+  "homepage": "https://www.phpbb.com",
+  "devDependencies": {
+    "stylelint": "^7.7.1",
+    "stylelint-order": "^0.3.0"
+  }
+}
diff --git a/phpBB/styles/prosilver/theme/common.css b/phpBB/styles/prosilver/theme/common.css
index c4eead7027..009d31ecab 100644
--- a/phpBB/styles/prosilver/theme/common.css
+++ b/phpBB/styles/prosilver/theme/common.css
@@ -93,9 +93,9 @@ p.right {
 }
 
 p.jumpbox-return {
+	float: left;
 	margin-top: 10px;
 	margin-bottom: 0;
-	float: left;
 }
 
 b,
@@ -1128,10 +1128,10 @@ ul.linklist:after,
 }
 
 .emoji {
-	min-height: 18px;
+	width: 1em;
 	min-width: 18px;
 	height: 1em;
-	width: 1em;
+	min-height: 18px;
 }
 
 .smilies {
@@ -1299,18 +1299,17 @@ ul.linklist:after,
 }
 
 .badge {
-	border-radius: 10px;
-	opacity: 0.8;
-	text-align: center;
-	white-space: nowrap;
 	font-size: 10px;
 	line-height: 1;
-	float: right;
-	display: inline-block;
-	margin-left: 3px;
-	vertical-align: baseline;
+	text-align: center;
+	white-space: nowrap;
+	border-radius: 10px;
+	opacity: 0.8;
 	position: relative;
 	top: 3px;
+	display: inline-block;
+	float: right;
+	margin-left: 3px;
 	padding: 4px 6px;
 }
 
diff --git a/phpBB/styles/prosilver/theme/content.css b/phpBB/styles/prosilver/theme/content.css
index a07876917d..88376d3430 100644
--- a/phpBB/styles/prosilver/theme/content.css
+++ b/phpBB/styles/prosilver/theme/content.css
@@ -515,11 +515,11 @@ blockquote cite > div {
 /* Code block */
 .codebox {
 	font-size: 1em;
+	word-wrap: normal;
 	border: 1px solid transparent;
+	overflow-x: scroll;
 	margin: 1em 0 1.2em;
 	padding: 3px;
-	overflow-x: scroll;
-	word-wrap: normal;
 }
 
 .codebox p {
diff --git a/phpBB/styles/prosilver/theme/responsive.css b/phpBB/styles/prosilver/theme/responsive.css
index ef4b398dd6..bc606e9723 100644
--- a/phpBB/styles/prosilver/theme/responsive.css
+++ b/phpBB/styles/prosilver/theme/responsive.css
@@ -623,7 +623,6 @@
 }
 
 @media (min-width: 701px) and (max-width: 950px) {
-
 	ul.topiclist dt {
 		margin-right: -410px;
 	}
diff --git a/travis/check-stylesheet.sh b/travis/check-stylesheet.sh
new file mode 100755
index 0000000000..a834833399
--- /dev/null
+++ b/travis/check-stylesheet.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+#
+# This file is part of the phpBB Forum Software package.
+#
+# @copyright (c) phpBB Limited <https://www.phpbb.com>
+# @license GNU General Public License, version 2 (GPL-2.0)
+#
+# For full copyright and license information, please see
+# the docs/CREDITS.txt file.
+#
+set -e
+set +x
+
+NOTESTS=$1
+
+if [ "$NOTESTS" == '1' ]
+then
+	cd phpBB
+	# Define a node version.
+	TRAVIS_NODE_VERSION="4"
+
+	# Clear out whatever version of NVM Travis has.
+	# Their version of NVM is probably old.
+	rm -rf ~/.nvm
+	# Grab NVM.
+	git clone https://github.com/creationix/nvm.git ~/.nvm > /dev/null
+	# Checkout the latest stable tag.
+	# Note that you can just hardcode a preferred version here.
+	(cd ~/.nvm && git checkout `git describe --abbrev=0 --tags`)
+	# Install the desired version of Node
+	source ~/.nvm/nvm.sh
+	nvm install $TRAVIS_NODE_VERSION > /dev/null
+	npm install -g > /dev/null
+	npm install > /dev/null
+	set -x
+	stylelint --config ../.stylelintrc "styles/prosilver/theme/*.css"
+	# Disable admin stylelint for now
+	# stylelint --config ../.stylelintrc "adm/style/*.css"
+fi