This Joomla 4 override allows you to customize the display of the 404 error page in Joomla. At the bottom of this article, you can download the files of the override.
Joomla 4 frontend rendering
PhP markup
<?php
/**
* @package Joomla.Site
* @subpackage Templates.cassiopeia
* @author web-eau.net
* @copyright (C) 2017 Open Source Matters, Inc. <https://www.joomla.org>
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/
defined('_JEXEC') or die;
use Joomla\CMS\Factory;
use Joomla\CMS\HTML\HTMLHelper;
use Joomla\CMS\Language\Text;
use Joomla\CMS\Uri\Uri;
/** @var Joomla\CMS\Document\ErrorDocument $this */
$app = Factory::getApplication();
$wa = $this->getWebAssetManager();
// Detecting Active Variables
$option = $app->input->getCmd('option', '');
$view = $app->input->getCmd('view', '');
$layout = $app->input->getCmd('layout', '');
$task = $app->input->getCmd('task', '');
$itemid = $app->input->getCmd('Itemid', '');
$sitename = htmlspecialchars($app->get('sitename'), ENT_QUOTES, 'UTF-8');
$menu = $app->getMenu()->getActive();
$pageclass = $menu !== null ? $menu->getParams()->get('pageclass_sfx', '') : '';
// Template path
$templatePath = 'templates/' . $this->template;
// Color Theme
$paramsColorName = $this->params->get('colorName', 'colors_standard');
$assetColorName = 'theme.' . $paramsColorName;
$wa->registerAndUseStyle($assetColorName, $templatePath . '/css/global/' . $paramsColorName . '.css');
// Use a font scheme if set in the template style options
$paramsFontScheme = $this->params->get('useFontScheme', false);
$fontStyles = '';
if ($paramsFontScheme)
{
if (stripos($paramsFontScheme, 'https://') === 0)
{
$this->getPreloadManager()->preconnect('https://fonts.googleapis.com/', ['crossorigin' => 'anonymous']);
$this->getPreloadManager()->preconnect('https://fonts.gstatic.com/', ['crossorigin' => 'anonymous']);
$this->getPreloadManager()->preload($paramsFontScheme, ['as' => 'style', 'crossorigin' => 'anonymous']);
$wa->registerAndUseStyle('fontscheme.current', $paramsFontScheme, [], ['media' => 'print', 'rel' => 'lazy-stylesheet', 'onload' => 'this.media=\'all\'', 'crossorigin' => 'anonymous']);
if (preg_match_all('/family=([^?:]*):/i', $paramsFontScheme, $matches) > 0)
{
$fontStyles = '--cassiopeia-font-family-body: "' . str_replace('+', ' ', $matches[1][0]) . '", sans-serif;
--cassiopeia-font-family-headings: "' . str_replace('+', ' ', isset($matches[1][1]) ? $matches[1][1] : $matches[1][0]) . '", sans-serif;
--cassiopeia-font-weight-normal: 400;
--cassiopeia-font-weight-headings: 700;';
}
}
else
{
$wa->registerAndUseStyle('fontscheme.current', $paramsFontScheme, ['version' => 'auto'], ['media' => 'print', 'rel' => 'lazy-stylesheet', 'onload' => 'this.media=\'all\'']);
$this->getPreloadManager()->preload($wa->getAsset('style', 'fontscheme.current')->getUri() . '?' . $this->getMediaVersion(), ['as' => 'style']);
}
}
// Enable assets
$wa->usePreset('template.cassiopeia.' . ($this->direction === 'rtl' ? 'rtl' : 'ltr'))
->useStyle('template.active.language')
->useStyle('template.user')
->useScript('template.user')
->addInlineStyle(":root {
--hue: 214;
--template-bg-light: #f0f4fb;
--template-text-dark: #495057;
--template-text-light: #ffffff;
--template-link-color: #2a69b8;
--template-special-color: #001B4C;
$fontStyles
}");
// Override 'template.active' asset to set correct ltr/rtl dependency
$wa->registerStyle('template.active', '', [], [], ['template.cassiopeia.' . ($this->direction === 'rtl' ? 'rtl' : 'ltr')]);
// Browsers support SVG favicons
$this->addHeadLink(HTMLHelper::_('image', 'joomla-favicon.svg', '', [], true, 1), 'icon', 'rel', ['type' => 'image/svg+xml']);
$this->addHeadLink(HTMLHelper::_('image', 'favicon.ico', '', [], true, 1), 'alternate icon', 'rel', ['type' => 'image/vnd.microsoft.icon']);
$this->addHeadLink(HTMLHelper::_('image', 'joomla-favicon-pinned.svg', '', [], true, 1), 'mask-icon', 'rel', ['color' => '#000']);
// Logo file or site title param
if ($this->params->get('logoFile'))
{
$logo = '<img src="' . htmlspecialchars(Uri::root() . $this->params->get('logoFile'), ENT_QUOTES, 'UTF-8') . '" alt="' . $sitename . '">';
}
elseif ($this->params->get('siteTitle'))
{
$logo = '<span title="' . $sitename . '">' . htmlspecialchars($this->params->get('siteTitle'), ENT_COMPAT, 'UTF-8') . '</span>';
}
else
{
$logo = '<img src="' . $this->baseurl . '/' . $templatePath. '/images/logo.svg" class="logo d-inline-block" alt="' . $sitename . '">';
}
// Container
$wrapper = $this->params->get('fluidContainer') ? 'wrapper-fluid' : 'wrapper-static';
$this->setMetaData('viewport', 'width=device-width, initial-scale=1');
// Defer font awesome
$wa->getAsset('style', 'fontawesome')->setAttribute('rel', 'lazy-stylesheet');
?>
<!DOCTYPE html>
<html lang="<?php echo $this->language; ?>" dir="<?php echo $this->direction; ?>">
<head>
<jdoc:include type="metas" />
<jdoc:include type="styles" />
<jdoc:include type="scripts" />
</head>
<body class="site error_site <?php echo $option
. ' ' . $wrapper
. ' view-' . $view
. ($layout ? ' layout-' . $layout : ' no-layout')
. ($task ? ' task-' . $task : ' no-task')
. ($itemid ? ' itemid-' . $itemid : '')
. ' ' . $pageclass;
echo ($this->direction == 'rtl' ? ' rtl' : '');
?>">
<header class="header container-header full-width">
<?php if ($this->params->get('brand', 1)) : ?>
<div class="grid-child">
<div class="navbar-brand">
<a class="brand-logo" href="<?php echo $this->baseurl; ?>/">
<?php echo $logo; ?>
</a>
<?php if ($this->params->get('siteDescription')) : ?>
<div class="site-description"><?php echo htmlspecialchars($this->params->get('siteDescription')); ?></div>
<?php endif; ?>
</div>
</div>
<?php endif; ?>
<?php if ($this->countModules('menu') || $this->countModules('search')) : ?>
<div class="grid-child container-nav">
<?php if ($this->countModules('menu')) : ?>
<jdoc:include type="modules" name="menu" style="none" />
<?php endif; ?>
<?php if ($this->countModules('search')) : ?>
<div class="container-search">
<jdoc:include type="modules" name="search" style="none" />
</div>
<?php endif; ?>
</div>
<?php endif; ?>
</header>
<div class="site-grid">
<div class="grid-child container-component">
<!-- custom 404 error page -->
<section class="error-page section">
<div class="row mx-auto text-center">
<div class="col-lg-6 offset-lg-3 col-12">
<div class="error-inner">
<h1 class="error-404-title">404<span>Oop's sorry we can't find that page!</span></h1>
<p>Aenean eget sollicitudin lorem, et pretium felis. Nullam euismod diam libero, sed dapibus leo laoreet ut. Suspendisse potenti. Phasellus urna lacus</p>
<!-- This is a fake search bar -->
<form class="search-form">
<input placeholder="Search from Here" type="text">
<button class="btn" type="submit"><i class="fa fa-search"></i></button>
</form>
<!-- To display a module here, use this snippet -->
<?php
$doc = JFactory::getDocument();
echo $doc->getBuffer('modules', 'name-of-the-module-position', array('style' => 'none'));
?>
</div>
</div>
</div>
</section>
<!-- custom 404 error page -->
</div>
</div>
<?php if ($this->countModules('footer')) : ?>
<footer class="container-footer footer full-width">
<div class="grid-child">
<jdoc:include type="modules" name="footer" style="none" />
</div>
</footer>
<?php endif; ?>
<jdoc:include type="modules" name="debug" style="none" />
</body>
</html>
CSS
.error-page {
padding-top: 65px;
text-align: center;
background: #fff;
border-top: 1px solid #eee;
}
.error-page .error-inner {
display: inline-block;
}
.error-page .error-inner h1 {
font-size: 165px;
text-shadow: 3px 5px 2px #3333;
color: #006DFE;
font-weight: 700;
}
.error-page .error-inner h1 span {
display: block;
font-size: 25px;
color: #333;
font-weight: 600;
text-shadow: none;
}
.error-page .error-inner p {
padding: 20px 15px;
}
.error-page .search-form {
width: 100%;
position: relative;
}
.error-page .search-form input {
width: 400px;
height: 50px;
padding: 0px 78px 0 30px;
border: none;
background: #f6f6f6;
border-radius: 5px;
display: inline-block;
margin-right: 10px;
font-weight:400;
font-size:14px;
}
.error-page .search-form input:hover{
padding-left:35px;
}
.error-page .search-form .btn {
width: 80px;
height: 50px;
border-radius: 5px;
cursor: pointer;
background: #006DFE;
display: inline-block;
position: relative;
top: -2px;
}
.error-page .search-form .btn i{
font-size:16px;
color: #fff;
}
.error-page .search-form .btn:hover{
background:#145889;
color: #fff;
}