diff --git a/.csslintrc b/.csslintrc
index 5b01fd13cdb..4203daade79 100644
--- a/.csslintrc
+++ b/.csslintrc
@@ -1,3 +1,3 @@
 --errors=errors,duplicate-properties
 --warnings=known-properties,display-property-grouping,empty-rules,important
---exclude-list=vendor/,lib/editor/tinymce/,lib/yuilib/,theme/bootstrapbase/style/
+--exclude-list=vendor/,node_modules/,lib/editor/tinymce/,lib/yuilib/,theme/bootstrapbase/style/,lib/jquery/,lib/htmlpurifier,theme/clean/style/custom.css,theme/more/style/custom.css,
diff --git a/enrol/yui/rolemanager/assets/skins/sam/rolemanager.css b/enrol/yui/rolemanager/assets/skins/sam/rolemanager.css
index af37580fbc9..ea01272e6a7 100644
--- a/enrol/yui/rolemanager/assets/skins/sam/rolemanager.css
+++ b/enrol/yui/rolemanager/assets/skins/sam/rolemanager.css
@@ -4,6 +4,5 @@
 .enrolpanel .container .header {border-bottom:1px solid #999;}
 .enrolpanel .container .header h2 {font-size:90%;text-align:center;margin:5px;}
 .enrolpanel .container .header .close {width:25px;height:15px;position:absolute;top:5px;right:1em;cursor:pointer;background:url("sprite.png") no-repeat scroll 0 0 transparent;}
-.enrolpanel .container .content {}
 .enrolpanel .container .content input {margin:5px;font-size:10px;}
 .enrolpanel.roleassign.visible .container {width:auto;}
diff --git a/lib/editor/atto/styles.css b/lib/editor/atto/styles.css
index 5c942e287d4..434b3e56ff3 100644
--- a/lib/editor/atto/styles.css
+++ b/lib/editor/atto/styles.css
@@ -38,7 +38,6 @@ div.editor_atto_toolbar button {
     margin: 0;
     border-radius: 0;
     cursor: pointer;
-    line-height: initial;
  }
 
 div.editor_atto_toolbar button + button {
diff --git a/report/progress/styles.css b/report/progress/styles.css
index b994b2b9bb5..feb55241d3a 100644
--- a/report/progress/styles.css
+++ b/report/progress/styles.css
@@ -17,7 +17,6 @@
 }
 #page-report-progress-index .completion_pagingbar p {
     display: inline;
-    margin: 0;
 }
 #page-report-progress-index .completion_next {
     display: inline;
diff --git a/theme/base/style/admin.css b/theme/base/style/admin.css
index 1dcdc365c6b..17edc0e3c3b 100644
--- a/theme/base/style/admin.css
+++ b/theme/base/style/admin.css
@@ -657,7 +657,6 @@
 }
 
 #adminsettings .form-item .form-setting .form-htmlarea {
-    width: 640px;
     display: inline;
 }
 
diff --git a/theme/base/style/autocomplete.css b/theme/base/style/autocomplete.css
index 08a3d550524..6c605070f56 100644
--- a/theme/base/style/autocomplete.css
+++ b/theme/base/style/autocomplete.css
@@ -9,7 +9,6 @@
 }
 
 .form-autocomplete-selection [role=listitem].label {
-    color: #333;
     background-color: #00E;
     border: 4px solid #00E;
     color: #FFF;
diff --git a/theme/base/style/calendar.css b/theme/base/style/calendar.css
index 6582c7dfec3..303c5aea567 100644
--- a/theme/base/style/calendar.css
+++ b/theme/base/style/calendar.css
@@ -48,9 +48,6 @@
     text-align: right;
 }
 
-.path-calendar {
-}
-
 .path-calendar .maincalendar {
     vertical-align: top;
     padding: 0;
diff --git a/theme/base/style/core.css b/theme/base/style/core.css
index 2b594bf4268..045cdac9ae5 100644
--- a/theme/base/style/core.css
+++ b/theme/base/style/core.css
@@ -464,7 +464,6 @@ div.hide {
     display: inline;
     border-width: 0;
     padding: 0;
-    margin: 0;
 }
 /*Accessibility: Skip block link, for keyboard-only users. */
 a.skip-block,
@@ -517,12 +516,6 @@ a.skip:active {
 /**
  * User menu
  */
-.usermenu {
-}
-
-.usermenu .moodle-actionmenu {
-}
-
 .usermenu .moodle-actionmenu .toggle-display {
     display: block;
     opacity: 1;
@@ -2063,9 +2056,6 @@ tr.flagged-tag a {
     color: inherit;
 }
 
-.path-backup .backup_progress .backup_stage.backup_stage_next {
-}
-
 .path-backup .backup_progress span.backup_stage.backup_stage_complete {
     color: inherit;
 }
@@ -2506,7 +2496,7 @@ x#fitem_id_availabilityconditionsjson input[type=text] {
 }
 
 .yui3-menu .yui3-menuitem.divider a {
-    visibility: invisible;
+    visibility: hidden;
 }
 
 /**
@@ -2732,8 +2722,6 @@ x#fitem_id_availabilityconditionsjson input[type=text] {
     display: inline;
     float: none;
     clear: none;
-    width: auto;
-    margin: 0;
     line-height: 2;
 }
 
@@ -2886,9 +2874,6 @@ x#fitem_id_availabilityconditionsjson input[type=text] {
     width: 50px;
 }
 
-.backup-restore .detail-pair {
-}
-
 .backup-restore .detail-pair-label {
     display: inline-block;
     width: 25%;
@@ -3414,7 +3399,6 @@ sup {
     margin: 0;
     line-height: 20px;
 }
-
 .moodle-dialogue-base .moodle-dialogue-wrap .moodle-dialogue-hd,
 .moodle-dialogue-base .moodle-dialogue-wrap .moodle-dialogue-hd.yui3-widget-hd {
     margin: 0;
@@ -3428,7 +3412,8 @@ sup {
     border-radius: 10px 10px 0px 0px;
     border-bottom: 1px solid #BBBBBB;
     background-color: #CCCCCC;
-    -ms-filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#FFFFFF', endColorstr='#CCCCCC')!important;
+    /*csslint important:false */
+    -ms-filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#FFFFFF', endColorstr='#CCCCCC') !important;
     -ms-filter: dropshadow(color=#FFFFFF, offx=1, offy=1);
     background-image: -webkit-linear-gradient(top, #FFFFFF, #CCCCCC);
     /* For Chrome and Safari */
@@ -3443,7 +3428,6 @@ sup {
 }
 
 .moodle-dialogue-base .moodle-dialogue-wrap .moodle-dialogue-hd h1 {
-    margin: 0;
     padding: 0;
     display: inline;
     font-size: 100%;
@@ -3457,7 +3441,6 @@ sup {
 .moodle-dialogue-base .closebutton {
     width: 25px;
     height: 15px;
-    float: right;
     vertical-align: middle;
     display: inline-block;
     cursor: pointer;
@@ -3876,8 +3859,6 @@ table.flexible .emptyrow {
     min-height: 225px;
 }
 
-.formlistingradiocontent {}
-
 .formlisting {
     position: relative;
     margin: 15px 0;
@@ -4330,7 +4311,7 @@ div#dateselector-calendar-panel {
 
 .jsenabled.dir-rtl .moodle-actionmenu[data-enhance] .toggle-display.textmenu {
     margin-right: 4px;
-    margin-left: initial;
+    margin-left: inherit;
 }
 
 .jsenabled .moodle-actionmenu[data-enhance] .toggle-display.textmenu .iconsmall {
@@ -4344,7 +4325,7 @@ div#dateselector-calendar-panel {
 
 .jsenabled.dir-rtl .moodle-actionmenu[data-enhance] .toggle-display.textmenu .caret {
     margin-right: 2px;
-    margin-left: initial;
+    margin-left: inherit;
 }
 
 .jsenabled .moodle-actionmenu[data-enhanced] .toggle-display {
@@ -4870,7 +4851,6 @@ body.lockscroll {
 
 .editor_atto_menu .moodle-dialogue-content {
     padding: 0;
-    border: inherit;
 }
 
 .well {
diff --git a/theme/base/style/course.css b/theme/base/style/course.css
index f903c0902f4..96142acbb34 100644
--- a/theme/base/style/course.css
+++ b/theme/base/style/course.css
@@ -105,7 +105,6 @@
 }
 
 .dir-rtl .section .activity .mod-indent-outer {
-    padding-left: auto;
     padding-right: 24px;
 }
 
@@ -158,7 +157,7 @@
 .dir-rtl.editing .sitetopic .section .activity .contentwithoutlink,
 .dir-rtl.editing .course-content .section .activity .contentwithoutlink {
     padding-left: 200px;
-    padding-right: initial;
+    padding-right: inherit;
 }
 
 .sitetopic .section .activity .activityinstance,
@@ -184,7 +183,7 @@
 .dir-rtl .sitetopic .section .activity .contentwithoutlink,
 .dir-rtl .course-content .section .activity .contentwithoutlink {
     padding-left: 32px;
-    padding-right: initial;
+    padding-right: inherit;
 }
 
 .sitetopic .section .activity .filler,
@@ -633,13 +632,13 @@ li.section.hidden span.commands a.editing_show {
 .course_category_tree .category > .info > .categoryname {
     background-image: url([[pix:moodle|t/collapsed_empty]]);
     background-repeat: no-repeat;
-    background-position: center left;
+    background-position: center;
     margin: 0.5em 5px;
 }
 
 .dir-rtl .course_category_tree .category > .info > .categoryname {
     background-image: url([[pix:moodle|t/collapsed_empty_rtl]]);
-    background-position: center right;
+    background-position: center;
     margin: 0.5em 5px;
 }
 
@@ -752,11 +751,11 @@ input.titleeditor {
 }
 
 .editing .course-content .section .activity.editor_displayed .activityinstance {
-    padding-right: initial;
+    padding-right: inherit;
 }
 
 .dir-rtl.editing .course-content .section .activity.editor_displayed .activityinstance {
-    padding-left: initial;
+    padding-left: inherit;
 }
 
 /* Course drag and drop upload styles */
@@ -809,7 +808,6 @@ input.titleeditor {
     display: inline-block;
     margin: 0;
     padding: 0;
-    float: left;
     box-shadow: 0 0 4px #229b15;
     border-radius: 2px;
     background-repeat: repeat-x;
@@ -1027,13 +1025,11 @@ input.titleeditor {
 #course-category-listings .item-actions {
     margin-right: 1em;
     display: inline-block;
-    display: initial;
 }
 
 #course-category-listings .item-actions .menubar img,
 #course-category-listings .item-actions > a img {
     margin: 0 4px;
-    vertical-align: inherit;
 }
 
 #course-category-listings .item-actions .menu img {
@@ -1293,7 +1289,6 @@ input.titleeditor {
 
 .coursecat-management-header > div {
     display: inline-block;
-    float: right;
 }
 
 .coursecat-management-header > div > div {
@@ -1428,6 +1423,8 @@ input.titleeditor {
 }
 
 /** Custom YUI grid CSS **/
+/*csslint duplicate-properties:false */
+
 
 .grid-col {
     display: inline-block;
@@ -1642,13 +1639,18 @@ input.titleeditor {
     word-spacing: -0.43em;
 }
 
-@media (min-width:980px) {
-    .grid-visible-phone     { display: none; }
-    .grid-visible-tablet    { display: none; }
-    .grid-visible-desktop   { }
-    .grid-hidden-phone      { }
-    .grid-hidden-tablet     { }
-    .grid-hidden-desktop    { display: none; }
+@media (min-width: 980px) {
+    .grid-visible-phone {
+        display: none;
+    }
+
+    .grid-visible-tablet {
+        display: none;
+    }
+
+    .grid-hidden-desktop {
+        display: none;
+    }
 }
 
 @media (min-width: 980px) {
@@ -1683,15 +1685,22 @@ input.titleeditor {
     .grid-visible-desktop {
         display: none;
     }
-    .grid-visible-phone     { }
-    .grid-hidden-phone      { display: none; }
-    .grid-hidden-desktop    { }
-    .grid-visible-desktop   { display: none; }
+
+    .grid-hidden-phone {
+        display: none;
+    }
+
+    .grid-visible-desktop {
+        display: none;
+    }
 }
 
-@media (min-width:768px) and (max-width:979px) {
-    .grid-visible-tablet    {}
-    .grid-hidden-tablet     { display: none; }
-    .grid-hidden-desktop    {}
-    .grid-visible-desktop   { display: none; }
+@media (min-width: 768px) and (max-width: 979px) {
+    .grid-hidden-tablet {
+        display: none;
+    }
+
+    .grid-visible-desktop {
+        display: none;
+    }
 }
diff --git a/theme/base/style/filemanager.css b/theme/base/style/filemanager.css
index c569c161db9..5be52ef7582 100644
--- a/theme/base/style/filemanager.css
+++ b/theme/base/style/filemanager.css
@@ -1,3 +1,5 @@
+/* We do nasty things in this stylesheet, disable some lints */
+/*csslint important:false,duplicate-properties:false */
 /**
  * File Picker and File Manager
  */
@@ -460,7 +462,6 @@
 
 .dir-rtl .fp-pathbar span {
     display: inline-block;
-    float: right;
     margin-left: 32px;
 }
 
@@ -1700,7 +1701,6 @@ a.ygtvspacer:hover {
         width: 100%;
         height: auto;
         max-height: 220px;
-        y-scroll: auto;
         float: none;
         border: 0px;
     }
diff --git a/theme/base/style/grade.css b/theme/base/style/grade.css
index 9cffa44bd4c..4d4e5962f7b 100644
--- a/theme/base/style/grade.css
+++ b/theme/base/style/grade.css
@@ -359,9 +359,6 @@
     padding: 1em;
 }
 
-#page-grade-grading-pick .templatesearchform {
-}
-
 #page-grade-grading-pick .template-name {
     clear: both;
     padding: 3px;
diff --git a/theme/base/style/message.css b/theme/base/style/message.css
index 9938ded8f27..84c8536ecfc 100644
--- a/theme/base/style/message.css
+++ b/theme/base/style/message.css
@@ -29,9 +29,6 @@
     font-style: italic;
 }
 
-.message .text {
-}
-
 #page-message-user .commands span {
     font-size: 0.7em;
 }
diff --git a/theme/base/style/pagelayout.css b/theme/base/style/pagelayout.css
index ffd05fb6491..13a6847b7f6 100644
--- a/theme/base/style/pagelayout.css
+++ b/theme/base/style/pagelayout.css
@@ -216,21 +216,6 @@ body {
     background-image: none;
 }
 
-/** Stabalise some IE6 behaviour **/
-.ie6 #region-pre .region-content,
-.ie6 #region-post .region-content {
-    padding: 0 !important;
-    width: 100%;
-    float: none;
-}
-
-.ie6 #region-pre .region-content .block,
-.ie6 #region-post .region-content .block {
-    width: auto;
-    padding: 0;
-    margin: 10px;
-}
-
 /** Report layout **/
 .pagelayout-report #page {
     width: auto;
diff --git a/theme/canvas/style/core.css b/theme/canvas/style/core.css
index 30d4d19e9cb..48e07189750 100644
--- a/theme/canvas/style/core.css
+++ b/theme/canvas/style/core.css
@@ -378,10 +378,6 @@ body {
 /* Roles
 ------------------------*/
 
-.path-admin-roles .generaltable {
-    /* width: 65%; hiding because it's causing problems on role/assign */
-}
-
 .path-admin-roles .generaltable th {
     vertical-align: middle;
 }
@@ -485,6 +481,7 @@ body {
 
 /* Comments
 -----------------------*/
+/*csslint important:false */
 
 .comment-list li {
     background: #eee !important;
diff --git a/theme/canvas/style/course.css b/theme/canvas/style/course.css
index a9b09a7d388..f94b5285fdb 100644
--- a/theme/canvas/style/course.css
+++ b/theme/canvas/style/course.css
@@ -95,22 +95,18 @@
 }
 
 #page-course-publish-metadata .hubscreenshot {
-    display:inline;
-    float:left;
-    margin-right:10px;
+    float: left;
+    margin-right: 10px;
 }
 
 #page-course-publish-metadata .hubscreenshot img {
     vertical-align: bottom;
 }
 
-#page-course-publish-metadata .hubdescription {}
-
 #page-course-publish-metadata .hubinfo {
     display: block;
     margin-bottom: 20px;
 }
-#page-course-publish-metadata .hublink {}
 
 #page-course-publish-backup .courseuploadtextinfo {
     text-align: center;
diff --git a/theme/canvas/style/mods.css b/theme/canvas/style/mods.css
index 824ff6fb3c0..8e1fc28b4dd 100644
--- a/theme/canvas/style/mods.css
+++ b/theme/canvas/style/mods.css
@@ -1,3 +1,4 @@
+/*csslint important:false */
 #intro {
     border-color: #ddd;
     margin: 2% 10%;
diff --git a/theme/canvas/style/popups.css b/theme/canvas/style/popups.css
index 2c7b04f3bb9..350014e87d1 100644
--- a/theme/canvas/style/popups.css
+++ b/theme/canvas/style/popups.css
@@ -1,3 +1,5 @@
+/*csslint important:false */
+
 body.pagelayout-popup {
     background: #fff !important;
-}
\ No newline at end of file
+}