diff --git a/resources/assets/css/admin.css b/resources/assets/css/admin.css
index 3315054..e85c07b 100644
--- a/resources/assets/css/admin.css
+++ b/resources/assets/css/admin.css
@@ -2,20 +2,11 @@
     margin-bottom: 15px;
 }
 
-.admin-sidebar-card .card-block {
-    padding: 10px;
-}
-
 .album-expand-handle {
     cursor: pointer;
     margin-top: 5px;
 }
 
-.card-header.card-danger {
-    color: #fff;
-    font-weight: bold;
-}
-
 .photo .loading {
     background-color: #ffffff;
     display: none;
diff --git a/resources/views/themes/base/admin/analyse_album.blade.php b/resources/views/themes/base/admin/analyse_album.blade.php
index 08a460c..4adec61 100644
--- a/resources/views/themes/base/admin/analyse_album.blade.php
+++ b/resources/views/themes/base/admin/analyse_album.blade.php
@@ -7,7 +7,7 @@
             <div class="col-sm-8 offset-sm-2" id="analyse-album">
                 <div class="card" v-if="!isCompleted">
                     <div class="card-header">Analysing...</div>
-                    <div class="card-block">
+                    <div class="card-body">
                         <p>Your uploaded photos are now being analysed.</p>
 
                         <div class="progress">
@@ -38,7 +38,7 @@
 
                 <div class="card" v-if="isCompleted">
                     <div class="card-header">Upload completed</div>
-                    <div class="card-block">
+                    <div class="card-body">
                         <p>Your upload has completed.</p>
 
                         <div v-if="numberFailed > 0">
diff --git a/resources/views/themes/base/admin/create_group.blade.php b/resources/views/themes/base/admin/create_group.blade.php
index 0dac776..ec5be41 100644
--- a/resources/views/themes/base/admin/create_group.blade.php
+++ b/resources/views/themes/base/admin/create_group.blade.php
@@ -19,13 +19,13 @@
                 <form action="{{ route('groups.store') }}" method="post">
                     {{ csrf_field() }}
                     <div class="row">
-                        <div class="col-md-6 offset-md-3">
-                            <div class="form-group{{ $errors->has('name') ? ' has-danger' : '' }}">
+                        <div class="col-md-6 ml-md-auto mr-md-auto">
+                            <div class="form-group">
                                 <label class="form-control-label" for="group-name">@lang('forms.name_label')</label>
-                                <input type="text" class="form-control" id="group-name" name="name" value="{{ old('name') }}">
+                                <input type="text" class="form-control{{ $errors->has('name') ? ' is-invalid' : '' }}" id="group-name" name="name" value="{{ old('name') }}">
 
                                 @if ($errors->has('name'))
-                                    <div class="form-control-feedback">
+                                    <div class="invalid-feedback">
                                         <strong>{{ $errors->first('name') }}</strong>
                                     </div>
                                 @endif
diff --git a/resources/views/themes/base/admin/create_storage.blade.php b/resources/views/themes/base/admin/create_storage.blade.php
index f6f6bad..ba8efb4 100644
--- a/resources/views/themes/base/admin/create_storage.blade.php
+++ b/resources/views/themes/base/admin/create_storage.blade.php
@@ -19,28 +19,28 @@
                 <form action="{{ route('storage.store') }}" method="post" id="storage-options">
                     {{ csrf_field() }}
 
-                    <div class="form-group{{ $errors->has('name') ? ' has-danger' : '' }}">
+                    <div class="form-group">
                         <label class="form-control-label" for="storage-name">@lang('forms.name_label')</label>
-                        <input type="text" class="form-control" id="storage-name" name="name" value="{{ old('name') }}">
+                        <input type="text" class="form-control{{ $errors->has('name') ? ' is-invalid' : '' }}" id="storage-name" name="name" value="{{ old('name') }}">
 
                         @if ($errors->has('name'))
-                            <div class="form-control-feedback">
+                            <div class="invalid-feedback">
                                 <strong>{{ $errors->first('name') }}</strong>
                             </div>
                         @endif
                     </div>
 
                     <div class="form-group">
-                        <div class="form-group{{ $errors->has('source') ? ' has-danger' : '' }}">
+                        <div class="form-group">
                             <label class="form-control-label" for="storage-source">@lang('forms.storage_driver_label')</label>
-                            <select id="storage-source" name="source" class="form-control" v-model="storage_driver">
+                            <select id="storage-source" name="source" class="form-control{{ $errors->has('source') ? ' is-invalid' : '' }}" v-model="storage_driver">
                                 @foreach ($album_sources as $key => $value)
                                     <option value="{{ $key }}"{{ old('source') == $key ? ' selected="selected"' : '' }}>{{ $value }}</option>
                                 @endforeach
                             </select>
 
                             @if ($errors->has('source'))
-                                <div class="form-control-feedback">
+                                <div class="invalid-feedback">
                                     <strong>{{ $errors->first('source') }}</strong>
                                 </div>
                             @endif
@@ -63,12 +63,11 @@
                         @include(Theme::viewName('partials.admin_storages_rackspace_options'))
                     </div>
 
-                    <div class="form-check">
-                        <label class="form-check-label">
-                            <input class="form-check-input" type="checkbox" name="is_default">
-                            @lang('forms.default_storage_label')
-                        </label>
-                    </div>
+                    <label class="custom-control custom-checkbox">
+                        <input type="checkbox" class="custom-control-input" name="is_default"@if (old('is_default')) checked="checked"@endif>
+                        <span class="custom-control-indicator"></span>
+                        <span class="custom-control-description">@lang('forms.default_storage_label')</span>
+                    </label>
 
                     <div class="text-right">
                         <a href="{{ route('storage.index') }}" class="btn btn-link">@lang('forms.cancel_action')</a>
diff --git a/resources/views/themes/base/admin/delete_album.blade.php b/resources/views/themes/base/admin/delete_album.blade.php
index 7ede600..32ffb2e 100644
--- a/resources/views/themes/base/admin/delete_album.blade.php
+++ b/resources/views/themes/base/admin/delete_album.blade.php
@@ -12,10 +12,10 @@
 @section('content')
     <div class="container">
         <div class="row">
-            <div class="col-md-8 offset-md-2">
-                <div class="card card-outline-danger">
-                    <div class="card-header card-danger">@yield('title')</div>
-                    <div class="card-block">
+            <div class="col-md-8 ml-md-auto mr-md-auto">
+                <div class="card bg-danger">
+                    <div class="card-header text-white">@yield('title')</div>
+                    <div class="card-body bg-light">
                         <p>@lang('admin.delete_album_confirm', ['name' => $album->name])</p>
                         <p class="text-danger"><b>@lang('admin.delete_album_warning')</b></p>
 
diff --git a/resources/views/themes/base/admin/delete_group.blade.php b/resources/views/themes/base/admin/delete_group.blade.php
index 6cb12b8..6b99759 100644
--- a/resources/views/themes/base/admin/delete_group.blade.php
+++ b/resources/views/themes/base/admin/delete_group.blade.php
@@ -11,10 +11,10 @@
 @section('content')
     <div class="container">
         <div class="row">
-            <div class="col-md-8 offset-md-2">
-                <div class="card card-outline-danger">
-                    <div class="card-header card-danger">@yield('title')</div>
-                    <div class="card-block">
+            <div class="col-md-8 ml-md-auto mr-md-auto">
+                <div class="card bg-danger">
+                    <div class="card-header text-white">@yield('title')</div>
+                    <div class="card-body bg-light">
                         <p>@lang('admin.delete_group_confirm', ['name' => $group->name])</p>
                         <p class="text-danger"><b>@lang('admin.delete_group_warning')</b></p>
 
diff --git a/resources/views/themes/base/admin/delete_storage.blade.php b/resources/views/themes/base/admin/delete_storage.blade.php
index d6eb1cd..d176bda 100644
--- a/resources/views/themes/base/admin/delete_storage.blade.php
+++ b/resources/views/themes/base/admin/delete_storage.blade.php
@@ -14,7 +14,7 @@
             <div class="col-md-8 offset-md-2">
                 <div class="card card-outline-danger">
                     <div class="card-header card-danger">@yield('title')</div>
-                    <div class="card-block">
+                    <div class="card-body">
                         <p>@lang('admin.delete_storage_confirm', ['name' => $storage->name])</p>
                         <p class="text-danger"><b>@lang('admin.delete_storage_warning')</b></p>
 
diff --git a/resources/views/themes/base/admin/delete_user.blade.php b/resources/views/themes/base/admin/delete_user.blade.php
index d39dd7a..47bf626 100644
--- a/resources/views/themes/base/admin/delete_user.blade.php
+++ b/resources/views/themes/base/admin/delete_user.blade.php
@@ -11,10 +11,10 @@
 @section('content')
     <div class="container">
         <div class="row">
-            <div class="col-md-8 offset-md-2">
-                <div class="card card-outline-danger">
-                    <div class="card-header card-danger">@yield('title')</div>
-                    <div class="card-block">
+            <div class="col-md-8 ml-md-auto mr-md-auto">
+                <div class="card bg-danger">
+                    <div class="card-header text-white">@yield('title')</div>
+                    <div class="card-body bg-light">
                         <p>@lang('admin.delete_user_confirm', ['name' => $user->name])</p>
                         <p class="text-danger"><b>@lang('admin.delete_user_warning')</b></p>
 
diff --git a/resources/views/themes/base/admin/edit_storage.blade.php b/resources/views/themes/base/admin/edit_storage.blade.php
index 93a8b4d..681e386 100644
--- a/resources/views/themes/base/admin/edit_storage.blade.php
+++ b/resources/views/themes/base/admin/edit_storage.blade.php
@@ -20,28 +20,30 @@
                     {{ method_field('PUT') }}
                     {{ csrf_field() }}
 
-                    <div class="form-group{{ $errors->has('name') ? ' has-danger' : '' }}">
+                    <div class="form-group">
                         <label class="form-control-label" for="storage-name">@lang('forms.name_label')</label>
-                        <input type="text" class="form-control" id="storage-name" name="name" value="{{ old('name') }}">
+                        <input type="text" class="form-control{{ $errors->has('name') ? ' is-invalid' : '' }}" id="storage-name" name="name" value="{{ old('name') }}">
 
                         @if ($errors->has('name'))
-                            <div class="form-control-feedback">
+                            <div class="invalid-feedback">
                                 <strong>{{ $errors->first('name') }}</strong>
                             </div>
                         @endif
                     </div>
 
-                    <div class="checkbox">
-                        <label>
-                            <input type="checkbox" name="is_default"@if ($storage->is_default) checked="checked"@endif>
-                            @lang('forms.default_storage_label')
+                    <div>
+                        <label class="custom-control custom-checkbox">
+                            <input type="checkbox" class="custom-control-input" name="is_default"@if (old('is_default', $storage->is_default)) checked="checked"@endif>
+                            <span class="custom-control-indicator"></span>
+                            <span class="custom-control-description">@lang('forms.default_storage_label')</span>
                         </label>
                     </div>
 
-                    <div class="checkbox">
-                        <label>
-                            <input type="checkbox" name="is_active"@if ($storage->is_active) checked="checked"@endif>
-                            @lang('forms.storage_active_label')
+                    <div>
+                        <label class="custom-control custom-checkbox">
+                            <input type="checkbox" class="custom-control-input" name="is_active"@if (old('is_active', $storage->is_active)) checked="checked"@endif>
+                            <span class="custom-control-indicator"></span>
+                            <span class="custom-control-description">@lang('forms.storage_active_label')</span>
                         </label>
                     </div>
 
diff --git a/resources/views/themes/base/admin/list_storage.blade.php b/resources/views/themes/base/admin/list_storage.blade.php
index 163c90d..20f7c69 100644
--- a/resources/views/themes/base/admin/list_storage.blade.php
+++ b/resources/views/themes/base/admin/list_storage.blade.php
@@ -66,7 +66,7 @@
                     <div class="row" style="margin-top: 15px;">
                         <div class="col-sm-6">
                             <div class="card card-outline-info">
-                                <div class="card-block">
+                                <div class="card-body">
                                     <h4 class="card-title">@lang('admin.legend')</h4>
                                     <p class="card-text">
                                         <i class="fa fa-fw fa-check text-success" style="font-size: 1.3em;"></i> @lang('admin.default_storage_legend')<br/>
diff --git a/resources/views/themes/base/admin/settings.blade.php b/resources/views/themes/base/admin/settings.blade.php
index 44d5915..6ae158c 100644
--- a/resources/views/themes/base/admin/settings.blade.php
+++ b/resources/views/themes/base/admin/settings.blade.php
@@ -82,12 +82,13 @@
                                 <fieldset>
                                     <legend>&quot;Powered by&quot; footer link</legend>
                                     <p>To help spread the word about Blue Twilight, I'd really appreciate it if you left the &quot;Powered by&quot; notice in your gallery's footer.</p>
-                                    <p>This is not compulsory, however, and you may remove it by checking the box below.</p>
+                                    <p>If you do want to remove it, however, I understand - just check the box below.</p>
 
                                     <div class="form-check" style="margin-top: 20px;">
-                                        <label class="form-check-label">
-                                            <input class="form-check-input" type="checkbox" name="remove_copyright" @if (old('remove_copyright', UserConfig::get('remove_copyright')))checked="checked"@endif>
-                                            <strong>Remove &quot;Powered by&quot; notice from the public gallery</strong>
+                                        <label class="custom-control custom-checkbox">
+                                            <input type="checkbox" class="custom-control-input" name="remove_copyright" @if (old('remove_copyright', UserConfig::get('remove_copyright')))checked="checked"@endif>
+                                            <span class="custom-control-indicator"></span>
+                                            <span class="custom-control-description"><strong>Remove &quot;Powered by&quot; notice from the public gallery</strong></span>
                                         </label>
                                     </div>
                                 </fieldset>
diff --git a/resources/views/themes/base/admin/show_album.blade.php b/resources/views/themes/base/admin/show_album.blade.php
index 63098d7..6b86bce 100644
--- a/resources/views/themes/base/admin/show_album.blade.php
+++ b/resources/views/themes/base/admin/show_album.blade.php
@@ -122,11 +122,11 @@
 
         {{-- Select All/None links on the permissions tab --}}
         $('a.select-all').click(function() {
-            $('input:checkbox', $(this).closest('.card-block')).prop('checked', true);
+            $('input:checkbox', $(this).closest('.card-body')).prop('checked', true);
             return false;
         });
         $('a.select-none').click(function() {
-            $('input:checkbox', $(this).closest('.card-block')).prop('checked', false);
+            $('input:checkbox', $(this).closest('.card-body')).prop('checked', false);
             return false;
         });
 
diff --git a/resources/views/themes/base/auth/passwords/change_password.blade.php b/resources/views/themes/base/auth/passwords/change_password.blade.php
index b967e2f..5ac797e 100644
--- a/resources/views/themes/base/auth/passwords/change_password.blade.php
+++ b/resources/views/themes/base/auth/passwords/change_password.blade.php
@@ -13,8 +13,8 @@
                             </li>
                         </ul>
                     </div>
-                    <div class="card-block">
-                        <form role="form" method="POST" action="{{ route('auth.processChangePassword') }}" class="mt-4">
+                    <div class="card-body">
+                        <form role="form" method="POST" action="{{ route('auth.processChangePassword') }}">
                             {{ csrf_field() }}
 
                             @if ($errors->has('email'))
diff --git a/resources/views/themes/base/auth/passwords/email.blade.php b/resources/views/themes/base/auth/passwords/email.blade.php
index 19e2c76..0ce9c27 100644
--- a/resources/views/themes/base/auth/passwords/email.blade.php
+++ b/resources/views/themes/base/auth/passwords/email.blade.php
@@ -13,8 +13,8 @@
                             </li>
                         </ul>
                     </div>
-                    <div class="card-block">
-                        <form role="form" method="POST" action="{{ url('/password/email') }}" class="mt-4">
+                    <div class="card-body">
+                        <form role="form" method="POST" action="{{ url('/password/email') }}">
                             {{ csrf_field() }}
 
                             <div class="form-group row{{ $errors->has('email') ? ' has-danger' : '' }}">
diff --git a/resources/views/themes/base/auth/passwords/reset.blade.php b/resources/views/themes/base/auth/passwords/reset.blade.php
index 271992c..89b0ac0 100644
--- a/resources/views/themes/base/auth/passwords/reset.blade.php
+++ b/resources/views/themes/base/auth/passwords/reset.blade.php
@@ -13,8 +13,8 @@
                             </li>
                         </ul>
                     </div>
-                    <div class="card-block">
-                        <form role="form" method="POST" action="{{ url('/password/reset') }}" class="mt-4">
+                    <div class="card-body">
+                        <form role="form" method="POST" action="{{ url('/password/reset') }}">
                             {{ csrf_field() }}
 
                             <input type="hidden" name="token" value="{{ $token }}">
diff --git a/resources/views/themes/base/auth/v2_unified.blade.php b/resources/views/themes/base/auth/v2_unified.blade.php
index e4398c9..a552173 100644
--- a/resources/views/themes/base/auth/v2_unified.blade.php
+++ b/resources/views/themes/base/auth/v2_unified.blade.php
@@ -18,7 +18,7 @@
                             @endif
                         </ul>
                     </div>
-                    <div class="card-block">
+                    <div class="card-body">
                         @if ($active_tab == 'login')
                             @include(Theme::viewName('partials.login'))
                         @elseif ($active_tab == 'register')
diff --git a/resources/views/themes/base/gallery/album_default.blade.php b/resources/views/themes/base/gallery/album_default.blade.php
index e06c9b8..51a2502 100644
--- a/resources/views/themes/base/gallery/album_default.blade.php
+++ b/resources/views/themes/base/gallery/album_default.blade.php
@@ -34,7 +34,7 @@
                         <div class="col-sm-6 col-md-4 photo mb-3">
                             <div class="card">
                                 <img src="{{ $photo->thumbnailUrl('preview') }}" alt="" class="card-img-top"/>
-                                <div class="card-block">
+                                <div class="card-body">
                                     <h4 class="card-title"><a href="{{ $photo->url() }}">{{ $photo->name }}</a></h4>
                                 </div>
                                 <div class="card-footer">
@@ -60,7 +60,7 @@
                             <div class="col-sm-4 col-md-3" style="max-width: 250px;">
                                 <div class="card mb-3">
                                     <img class="card-img-top" src="{{ $childAlbum->thumbnailUrl('preview') }}" style="max-height: 120px;"/>
-                                    <div class="card-block">
+                                    <div class="card-body">
                                         <h5 class="card-title"><a href="{{ $childAlbum->url() }}">{{ $childAlbum->name }}</a></h5>
                                     </div>
                                     <div class="card-footer">
diff --git a/resources/views/themes/base/gallery/album_empty.blade.php b/resources/views/themes/base/gallery/album_empty.blade.php
index 297ed31..4a2aff6 100644
--- a/resources/views/themes/base/gallery/album_empty.blade.php
+++ b/resources/views/themes/base/gallery/album_empty.blade.php
@@ -6,7 +6,7 @@
 @section('content')
     <div class="container-fluid album-container">
         <div class="row">
-            <div class="col-xl-8 offset-xl-2">
+            <div class="col-8 ml-auto mr-auto">
                 <div class="row">
                     <div class="col">
                         <ol class="breadcrumb">
@@ -35,7 +35,7 @@
                             <div class="col-sm-4 col-md-3" style="max-width: 250px;">
                                 <div class="card mb-3">
                                     <img class="card-img-top" src="{{ $childAlbum->thumbnailUrl('preview') }}" style="max-height: 120px;"/>
-                                    <div class="card-block">
+                                    <div class="card-body">
                                         <h5 class="card-title"><a href="{{ $childAlbum->url() }}">{{ $childAlbum->name }}</a></h5>
                                     </div>
                                     <div class="card-footer">
diff --git a/resources/views/themes/base/gallery/album_slideshow.blade.php b/resources/views/themes/base/gallery/album_slideshow.blade.php
index 2678a25..ead93e0 100644
--- a/resources/views/themes/base/gallery/album_slideshow.blade.php
+++ b/resources/views/themes/base/gallery/album_slideshow.blade.php
@@ -59,7 +59,7 @@
                 <div class="col-sm-4 col-md-3" style="max-width: 250px;">
                     <div class="card mb-3">
                         <img class="card-img-top" src="{{ $childAlbum->thumbnailUrl('preview') }}" style="max-height: 120px;"/>
-                        <div class="card-block">
+                        <div class="card-body">
                             <h5 class="card-title"><a href="{{ $childAlbum->url() }}">{{ $childAlbum->name }}</a></h5>
                         </div>
                         <div class="card-footer">
diff --git a/resources/views/themes/base/gallery/index.blade.php b/resources/views/themes/base/gallery/index.blade.php
index 1e4b24b..df6427b 100644
--- a/resources/views/themes/base/gallery/index.blade.php
+++ b/resources/views/themes/base/gallery/index.blade.php
@@ -11,7 +11,7 @@
                             <div class="col-sm-6 col-md-4">
                                 <div class="card">
                                     <img class="card-img-top" src="{{ $album->thumbnailUrl('preview') }}"/>
-                                    <div class="card-block">
+                                    <div class="card-body">
                                         <h4 class="card-title"><a href="{{ $album->url() }}">{{ $album->name }}</a></h4>
                                         <p class="card-text">{{ $album->description }}</p>
                                     </div>
diff --git a/resources/views/themes/base/gallery/photo.blade.php b/resources/views/themes/base/gallery/photo.blade.php
index cd0726c..0cf83c5 100644
--- a/resources/views/themes/base/gallery/photo.blade.php
+++ b/resources/views/themes/base/gallery/photo.blade.php
@@ -32,7 +32,7 @@
             <div class="col-sm-4">
                 <div class="card">
                     <div class="card-header">Information about this photo:</div>
-                    <div class="card-block" style="padding: 0;">
+                    <div class="card-body" style="padding: 0;">
                         <table class="table table-striped photo-metadata mb-0">
                             <thead>
                                 <tr>
diff --git a/resources/views/themes/base/partials/admin_actions_widget.blade.php b/resources/views/themes/base/partials/admin_actions_widget.blade.php
index 281533b..e063fbb 100644
--- a/resources/views/themes/base/partials/admin_actions_widget.blade.php
+++ b/resources/views/themes/base/partials/admin_actions_widget.blade.php
@@ -1,7 +1,7 @@
 @can('admin:manage-albums')
     <div class="card admin-sidebar-card">
         <div class="card-header">@lang('admin.actions_widget.panel_header')</div>
-        <div class="card-block">
+        <div class="card-body">
             <a class="btn btn-link" href="{{ route('albums.create') }}"><i class="fa fa-fw fa-plus"></i> @lang('admin.actions_widget.create_album_link')</a>
         </div>
     </div>
diff --git a/resources/views/themes/base/partials/admin_manage_widget.blade.php b/resources/views/themes/base/partials/admin_manage_widget.blade.php
index 2fe6694..fc92260 100644
--- a/resources/views/themes/base/partials/admin_manage_widget.blade.php
+++ b/resources/views/themes/base/partials/admin_manage_widget.blade.php
@@ -9,7 +9,7 @@
 @if ($canConfigure || $canManageAlbums || $canManageGroups || $canManageStorage || $canManageUsers)
     <div class="card admin-sidebar-card">
         <div class="card-header">@lang('admin.manage_widget.panel_header')</div>
-        <div class="card-block">
+        <div class="card-body">
             @if ($canManageAlbums)
                 <a class="btn btn-link" href="{{ route('albums.index') }}"><i class="fa fa-fw fa-picture-o"></i> @lang('navigation.breadcrumb.albums')</a>
             @endif
diff --git a/resources/views/themes/base/partials/admin_stats_widget.blade.php b/resources/views/themes/base/partials/admin_stats_widget.blade.php
index 9a07cf3..744b273 100644
--- a/resources/views/themes/base/partials/admin_stats_widget.blade.php
+++ b/resources/views/themes/base/partials/admin_stats_widget.blade.php
@@ -1,6 +1,6 @@
 <div class="card admin-sidebar-card">
     <div class="card-header">@lang('admin.stats_widget.panel_header')</div>
-    <div class="card-block">
+    <div class="card-body">
         <b>{{ $album_count }}</b> {{ trans_choice('admin.stats_widget.albums', $album_count) }}<br/>
         <b>{{ $photo_count }}</b> {{ trans_choice('admin.stats_widget.photos', $photo_count) }}
         @can('admin:access')
diff --git a/resources/views/themes/base/partials/admin_storages_amazon_s3_options.blade.php b/resources/views/themes/base/partials/admin_storages_amazon_s3_options.blade.php
index 8af7b12..93e3164 100644
--- a/resources/views/themes/base/partials/admin_storages_amazon_s3_options.blade.php
+++ b/resources/views/themes/base/partials/admin_storages_amazon_s3_options.blade.php
@@ -1,23 +1,23 @@
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('access_key') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="access-key">@lang('forms.storage_access_key_label')</label>
-            <input type="text" class="form-control" id="access-key" name="access_key" value="{{ old('access_key') }}">
+            <input type="text" class="form-control{{ $errors->has('access_key') ? ' is-invalid' : '' }}" id="access-key" name="access_key" value="{{ old('access_key') }}">
 
             @if ($errors->has('access_key'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('access_key') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('secret_key') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="secret-key">@lang('forms.storage_secret_key_label')</label>
-            <input type="text" class="form-control" id="secret-key" name="secret_key" value="{{ old('secret_key') }}">
+            <input type="text" class="form-control{{ $errors->has('secret_key') ? ' is-invalid' : '' }}" id="secret-key" name="secret_key" value="{{ old('secret_key') }}">
 
             @if ($errors->has('secret_key'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('secret_key') }}</strong>
                 </div>
             @endif
@@ -27,24 +27,24 @@
 
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('container_name') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="container-name">@lang('forms.storage_bucket_name_label')</label>
-            <input type="text" class="form-control" id="container-name" name="container_name" value="{{ old('container_name') }}">
+            <input type="text" class="form-control{{ $errors->has('container_name') ? ' is-invalid' : '' }}" id="container-name" name="container_name" value="{{ old('container_name') }}">
 
             @if ($errors->has('container_name'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('container_name') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('service_region') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="service-region">@lang('forms.storage_service_region_label')</label>
-            <input type="text" class="form-control" id="service-region" name="service_region" value="{{ old('service_region') }}">
+            <input type="text" class="form-control{{ $errors->has('service_region') ? ' is-invalid' : '' }}" id="service-region" name="service_region" value="{{ old('service_region') }}">
 
             @if ($errors->has('service_region'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('service_region') }}</strong>
                 </div>
             @endif
@@ -52,12 +52,12 @@
     </div>
 </div>
 
-<div class="form-group{{ $errors->has('auth_url') ? ' has-danger' : '' }}">
+<div class="form-group">
     <label class="form-control-label" for="auth-url">@lang('forms.storage_auth_url_label')</label>
-    <input type="text" class="form-control" id="auth-url" name="auth_url" value="{{ old('auth_url') }}">
+    <input type="text" class="form-control{{ $errors->has('auth_url') ? ' is-invalid' : '' }}" id="auth-url" name="auth_url" value="{{ old('auth_url') }}">
 
     @if ($errors->has('auth_url'))
-        <div class="form-control-feedback">
+        <div class="invalid-feedback">
             <strong>{{ $errors->first('auth_url') }}</strong>
         </div>
     @endif
diff --git a/resources/views/themes/base/partials/admin_storages_filesystem_options.blade.php b/resources/views/themes/base/partials/admin_storages_filesystem_options.blade.php
index bd4ab6e..a4481de 100644
--- a/resources/views/themes/base/partials/admin_storages_filesystem_options.blade.php
+++ b/resources/views/themes/base/partials/admin_storages_filesystem_options.blade.php
@@ -1,9 +1,9 @@
-<div class="form-group{{ $errors->has('location') ? ' has-danger' : '' }}">
+<div class="form-group">
     <label class="form-control-label" for="storage-location">@lang('forms.storage_location_label')</label>
-    <input type="text" class="form-control" id="storage-location" name="location" value="{{ old('location', isset($filesystem_default_location) ? $filesystem_default_location : '') }}">
+    <input type="text" class="form-control{{ $errors->has('location') ? ' is-invalid' : '' }}" id="storage-location" name="location" value="{{ old('location', isset($filesystem_default_location) ? $filesystem_default_location : '') }}">
 
     @if ($errors->has('location'))
-        <div class="form-control-feedback">
+        <div class="invalid-feedback">
             <strong>{{ $errors->first('location') }}</strong>
         </div>
     @endif
diff --git a/resources/views/themes/base/partials/admin_storages_openstack_options.blade.php b/resources/views/themes/base/partials/admin_storages_openstack_options.blade.php
index 62f9b4c..0df51f5 100644
--- a/resources/views/themes/base/partials/admin_storages_openstack_options.blade.php
+++ b/resources/views/themes/base/partials/admin_storages_openstack_options.blade.php
@@ -1,23 +1,23 @@
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('auth_url') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="auth-url">@lang('forms.storage_auth_url_label')</label>
-            <input type="text" class="form-control" id="auth-url" name="auth_url" value="{{ old('auth_url') }}">
+            <input type="text" class="form-control{{ $errors->has('auth_url') ? ' is-invalid' : '' }}" id="auth-url" name="auth_url" value="{{ old('auth_url') }}">
 
             @if ($errors->has('auth_url'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('auth_url') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('tenant_name') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="tenant-name">@lang('forms.storage_tenant_name_label')</label>
-            <input type="text" class="form-control" id="tenant-name" name="tenant_name" value="{{ old('tenant_name') }}">
+            <input type="text" class="form-control{{ $errors->has('tenant_name') ? ' is-invalid' : '' }}" id="tenant-name" name="tenant_name" value="{{ old('tenant_name') }}">
 
             @if ($errors->has('tenant_name'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('tenant_name') }}</strong>
                 </div>
             @endif
@@ -27,24 +27,24 @@
 
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('username') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="username">@lang('forms.username_label')</label>
-            <input type="text" class="form-control" id="username" name="username" value="{{ old('username') }}">
+            <input type="text" class="form-control{{ $errors->has('username') ? ' is-invalid' : '' }}" id="username" name="username" value="{{ old('username') }}">
 
             @if ($errors->has('username'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('username') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('password') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="password">@lang('forms.password_label')</label>
-            <input type="text" class="form-control" id="password" name="password" value="{{ old('password') }}">
+            <input type="text" class="form-control{{ $errors->has('password') ? ' is-invalid' : '' }}" id="password" name="password" value="{{ old('password') }}">
 
             @if ($errors->has('password'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('password') }}</strong>
                 </div>
             @endif
@@ -54,24 +54,24 @@
 
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('service_name') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="service-name">@lang('forms.storage_service_name_label')</label>
-            <input type="text" class="form-control" id="service-name" name="service_name" value="{{ old('service_name') }}">
+            <input type="text" class="form-control{{ $errors->has('service_name') ? ' is-invalid' : '' }}" id="service-name" name="service_name" value="{{ old('service_name') }}">
 
             @if ($errors->has('service_name'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('service_name') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('service_region') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="service-region">@lang('forms.storage_service_region_label')</label>
-            <input type="text" class="form-control" id="service-region" name="service_region" value="{{ old('service_region') }}">
+            <input type="text" class="form-control{{ $errors->has('service_region') ? ' is-invalid' : '' }}" id="service-region" name="service_region" value="{{ old('service_region') }}">
 
             @if ($errors->has('service_region'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('service_region') }}</strong>
                 </div>
             @endif
@@ -79,23 +79,23 @@
     </div>
 </div>
 
-<div class="form-group{{ $errors->has('container_name') ? ' has-danger' : '' }}">
+<div class="form-group">
     <label class="form-control-label" for="container-name">@lang('forms.storage_container_name_label')</label>
-    <input type="text" class="form-control" id="container-name" name="container_name" value="{{ old('container_name') }}">
+    <input type="text" class="form-control{{ $errors->has('container_name') ? ' is-invalid' : '' }}" id="container-name" name="container_name" value="{{ old('container_name') }}">
 
     @if ($errors->has('container_name'))
-        <div class="form-control-feedback">
+        <div class="invalid-feedback">
             <strong>{{ $errors->first('container_name') }}</strong>
         </div>
     @endif
 </div>
 
-<div class="form-group{{ $errors->has('cdn_url') ? ' has-danger' : '' }}">
+<div class="form-group">
     <label class="form-control-label" for="cdn-url">@lang('forms.storage_cdn_url_label')</label>
-    <input type="text" class="form-control" id="cdn-url" name="cdn_url" value="{{ old('cdn_url') }}">
+    <input type="text" class="form-control{{ $errors->has('cdn_url') ? ' is-invalid' : '' }}" id="cdn-url" name="cdn_url" value="{{ old('cdn_url') }}">
 
     @if ($errors->has('cdn_url'))
-        <div class="form-control-feedback">
+        <div class="invalid-feedback">
             <strong>{{ $errors->first('cdn_url') }}</strong>
         </div>
     @endif
diff --git a/resources/views/themes/base/partials/admin_storages_rackspace_options.blade.php b/resources/views/themes/base/partials/admin_storages_rackspace_options.blade.php
index 753ff26..8b4a852 100644
--- a/resources/views/themes/base/partials/admin_storages_rackspace_options.blade.php
+++ b/resources/views/themes/base/partials/admin_storages_rackspace_options.blade.php
@@ -1,23 +1,23 @@
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('username') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="username">@lang('forms.username_label')</label>
-            <input type="text" class="form-control" id="username" name="username" value="{{ old('username') }}">
+            <input type="text" class="form-control{{ $errors->has('username') ? ' is-invalid' : '' }}" id="username" name="username" value="{{ old('username') }}">
 
             @if ($errors->has('username'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('username') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('password') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="password">@lang('forms.password_label')</label>
-            <input type="text" class="form-control" id="password" name="password" value="{{ old('password') }}">
+            <input type="text" class="form-control{{ $errors->has('password') ? ' is-invalid' : '' }}" id="password" name="password" value="{{ old('password') }}">
 
             @if ($errors->has('password'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('password') }}</strong>
                 </div>
             @endif
@@ -27,24 +27,24 @@
 
 <div class="row">
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('service_region') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="service-region">@lang('forms.storage_service_region_label')</label>
-            <input type="text" class="form-control" id="service-region" name="service_region" value="{{ old('service_region') }}">
+            <input type="text" class="form-control{{ $errors->has('service_region') ? ' is-invalid' : '' }}" id="service-region" name="service_region" value="{{ old('service_region') }}">
 
             @if ($errors->has('service_region'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('service_region') }}</strong>
                 </div>
             @endif
         </div>
     </div>
     <div class="col-md-6">
-        <div class="form-group{{ $errors->has('container_name') ? ' has-danger' : '' }}">
+        <div class="form-group">
             <label class="form-control-label" for="container-name">@lang('forms.storage_container_name_label')</label>
-            <input type="text" class="form-control" id="container-name" name="container_name" value="{{ old('container_name') }}">
+            <input type="text" class="form-control{{ $errors->has('container_name') ? ' is-invalid' : '' }}" id="container-name" name="container_name" value="{{ old('container_name') }}">
 
             @if ($errors->has('container_name'))
-                <div class="form-control-feedback">
+                <div class="invalid-feedback">
                     <strong>{{ $errors->first('container_name') }}</strong>
                 </div>
             @endif
diff --git a/resources/views/themes/base/partials/admin_sysinfo_widget.blade.php b/resources/views/themes/base/partials/admin_sysinfo_widget.blade.php
index e7c3565..6499731 100644
--- a/resources/views/themes/base/partials/admin_sysinfo_widget.blade.php
+++ b/resources/views/themes/base/partials/admin_sysinfo_widget.blade.php
@@ -1,6 +1,6 @@
 <div class="card">
     <div class="card-header">@lang('admin.sysinfo_panel')</div>
-    <div class="card-block" style="padding: 0;">
+    <div class="card-body" style="padding: 0;">
         <table id="system-info" class="table my-0 table-striped">
             <tbody>
                 <tr>
diff --git a/resources/views/themes/base/partials/album_permissions.blade.php b/resources/views/themes/base/partials/album_permissions.blade.php
index ea3cf5e..6684d9a 100644
--- a/resources/views/themes/base/partials/album_permissions.blade.php
+++ b/resources/views/themes/base/partials/album_permissions.blade.php
@@ -5,7 +5,7 @@
         </h5>
     </div>
     <div id="collapse-{{ $key_id }}" class="panel-collapse collapse" role="tabpanel" aria-labelledby="heading-{{ $key_id }}">
-        <div class="card-block">
+        <div class="card-body">
             <p style="margin-bottom: 20px;"><a class="select-all" href="#">Select All</a> &middot; <a class="select-none" href="">Select None</a></p>
 
             <div class="row">
diff --git a/resources/views/themes/base/partials/album_settings_tab.blade.php b/resources/views/themes/base/partials/album_settings_tab.blade.php
index 1ebf78c..51b5441 100644
--- a/resources/views/themes/base/partials/album_settings_tab.blade.php
+++ b/resources/views/themes/base/partials/album_settings_tab.blade.php
@@ -42,7 +42,7 @@
             <div class="col-md-6 push-md-6 mb-3">
                 <div class="card">
                     <div class="card-header">@lang('admin.save_changes_heading')</div>
-                    <div class="card-block">
+                    <div class="card-body">
                         <p>@lang('admin.save_changes_intro')</p>
                         <div class="text-right">
                             <button type="submit" class="btn btn-success"><i class="fa fa-fw fa-floppy-o"></i> @lang('forms.save_action')</button>
@@ -53,9 +53,9 @@
 
             @can('delete', $album)
                 <div class="col-md-6 pull-md-6 mb-3">
-                    <div class="card card-outline-danger">
-                        <div class="card-header card-danger">@lang('admin.danger_zone_heading')</div>
-                        <div class="card-block">
+                    <div class="card bg-danger">
+                        <div class="card-header text-white">@lang('admin.danger_zone_heading')</div>
+                        <div class="card-body bg-light">
                             <p class="text-danger">@lang('admin.danger_zone_intro')</p>
                             <div>
                                 <a href="{{ route('albums.delete', ['id' => $album->id]) }}" class="btn btn-danger">@lang('forms.delete_action')</a>
diff --git a/resources/views/themes/base/partials/login.blade.php b/resources/views/themes/base/partials/login.blade.php
index 38cabd5..b9fe690 100644
--- a/resources/views/themes/base/partials/login.blade.php
+++ b/resources/views/themes/base/partials/login.blade.php
@@ -1,4 +1,4 @@
-<form role="form" method="POST" action="{{ url('/login') }}" class="mt-4">
+<form role="form" method="POST" action="{{ url('/login') }}">
     {{ csrf_field() }}
 
     <div class="form-group row{{ $errors->has('email') ? ' has-danger' : '' }}">
diff --git a/resources/views/themes/base/partials/register.blade.php b/resources/views/themes/base/partials/register.blade.php
index 97d235d..c568f89 100644
--- a/resources/views/themes/base/partials/register.blade.php
+++ b/resources/views/themes/base/partials/register.blade.php
@@ -1,4 +1,4 @@
-<form role="form" method="POST" action="{{ url('/register') }}" class="mt-4">
+<form role="form" method="POST" action="{{ url('/register') }}">
     {{ csrf_field() }}
 
     <div class="form-group row{{ $errors->has('name') ? ' has-danger' : '' }}">