<title>Bootstrap 4 Simple Alerts</title>
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<div class="alert alert-primary">
<strong>Primary!</strong> A simple primary alert.
<div class="alert alert-secondary">
<strong>Secondary!</strong> A simple secondary alert.
<div class="alert alert-success">
<strong>Success!</strong> A simple success alert.
<div class="alert alert-danger">
<strong>Danger!</strong> A simple danger alert.
<div class="alert alert-warning">
<strong>Warning!</strong> A simple warning alert.
<div class="alert alert-info">
<strong>Info!</strong> A simple info alert.
<div class="alert alert-light">
<strong>Light!</strong> A simple light alert.
<div class="alert alert-dark">
<strong>Dark!</strong> A simple dark alert.