Add Themes: Dark, light and automatic mode

app/Template/layout.php

@@ -14,7 +14,11 @@
 
         <?= $this->asset->colorCss() ?>
         <?= $this->asset->css('assets/css/vendor.min.css') ?>
-        <?= $this->asset->css('assets/css/app.min.css') ?>
+        <?php if (! isset($not_editable)): ?>
+            <?= $this->asset->css('assets/css/'.$this->user->getTheme().'.min.css') ?>
+        <?php else: ?>
+            <?= $this->asset->css('assets/css/light.min.css') ?>
+        <?php endif ?>
         <?= $this->asset->css('assets/css/print.min.css', true, 'print') ?>
         <?= $this->asset->customCss() ?>
 

app/Template/user_modification/show.php

@@ -19,6 +19,9 @@
 
     <fieldset>
         <legend><?= t('Preferences') ?></legend>
+        <?= $this->form->label(t('Theme'), 'theme') ?>
+        <?= $this->form->select('theme', $themes, $values, $errors, array($this->user->hasAccess('UserModificationController', 'show/edit_theme') ? '' : 'disabled')) ?>
+
         <?= $this->form->label(t('Timezone'), 'timezone') ?>
         <?= $this->form->select('timezone', $timezones, $values, $errors, array($this->user->hasAccess('UserModificationController', 'show/edit_timezone') ? '' : 'disabled')) ?>
 

app/Template/user_view/show.php

@@ -32,6 +32,7 @@
     <h2><?= t('Preferences') ?></h2>
 </div>
 <ul class="panel">
+    <li><?= t('Theme:') ?> <strong><?= $this->text->in($user['theme'], $themes) ?></strong></li>
     <li><?= t('Timezone:') ?> <strong><?= $this->text->in($user['timezone'], $timezones) ?></strong></li>
     <li><?= t('Language:') ?> <strong><?= $this->text->in($user['language'], $languages) ?></strong></li>
     <li><?= t('Custom Filter:') ?> <strong><?= $this->text->e($user['filter']) ?></strong></li>