Run `grunt`.

docs/_includes/customizer-variables.html

@@ -467,6 +467,11 @@
     <p id="help-block-@input-height-small" class="help-block">Small <code>.form-control</code> height</p>
   </div>
   <div class="clearfix"></div>
+  <div class="col-xs-4">
+    <label for="input-@form-group-margin-bottom">@form-group-margin-bottom</label>
+    <input id="input-@form-group-margin-bottom" type="text" aria-describedby="help-block-@form-group-margin-bottom" value="15px" data-var="@form-group-margin-bottom" class="form-control"/>
+    <p id="help-block-@form-group-margin-bottom" class="help-block"><code>.form-group</code> margin</p>
+  </div>
   <div class="col-xs-4">
     <label for="input-@legend-color">@legend-color</label>
     <input id="input-@legend-color" type="text" value="@gray-dark" data-var="@legend-color" class="form-control"/>
@@ -475,12 +480,12 @@
     <label for="input-@legend-border-color">@legend-border-color</label>
     <input id="input-@legend-border-color" type="text" value="#e5e5e5" data-var="@legend-border-color" class="form-control"/>
   </div>
+  <div class="clearfix"></div>
   <div class="col-xs-4">
     <label for="input-@input-group-addon-bg">@input-group-addon-bg</label>
     <input id="input-@input-group-addon-bg" type="text" aria-describedby="help-block-@input-group-addon-bg" value="@gray-lighter" data-var="@input-group-addon-bg" class="form-control"/>
     <p id="help-block-@input-group-addon-bg" class="help-block">Background color for textual input addons</p>
   </div>
-  <div class="clearfix"></div>
   <div class="col-xs-4">
     <label for="input-@input-group-addon-border-color">@input-group-addon-border-color</label>
     <input id="input-@input-group-addon-border-color" type="text" aria-describedby="help-block-@input-group-addon-border-color" value="@input-border" data-var="@input-group-addon-border-color" class="form-control"/>

docs/dist/css/bootstrap.css

@@ -3409,7 +3409,7 @@ tbody.collapse.in {
   height: 0;
   margin-left: 2px;
   vertical-align: middle;
-  border-top: 4px solid;
+  border-top: 4px dashed;
   border-right: 4px solid transparent;
   border-left: 4px solid transparent;
 }
@@ -5658,10 +5658,10 @@ a.list-group-item-danger.active:focus {
   height: 100%;
   border: 0;
 }
-.embed-responsive.embed-responsive-16by9 {
+.embed-responsive-16by9 {
   padding-bottom: 56.25%;
 }
-.embed-responsive.embed-responsive-4by3 {
+.embed-responsive-4by3 {
   padding-bottom: 75%;
 }
 .well {