public/500.html
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<head>
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<title>Somleng - 500</title>
<link href="https://unpkg.com/@coreui/coreui@4.1.5/dist/css/coreui.min.css" rel="stylesheet">
</head>
<body class="c-app flex-row align-items-center">
<div class="container">
<div class="row justify-content-center">
<div class="col-md-6">
<div class="clearfix">
<h1 class="float-left display-3 mr-4">500</h1>
<h4 class="pt-3">Oops! Something went wrong.</h4>
<p class="text-muted">The page you are looking for is temporarily unavailable.</p>
</div>
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