<button class="btn"> Button</button><br>
<button class="btn btn-primary">Primary Button</button>
<button class="btn btn-secondary">Secondary Button</button>
<button class="btn btn-success">Success Button</button>
<button class="btn btn-warning">Warning Button</button>
<button class="btn btn-info btn-sm">Info Small Button</button>
<button class="btn btn-light">Light Button</button>
<button class="btn btn-dark">Dark Button</button>
<button class="btn btn-danger btn-lg">Danger Large Button</button> <br>
<button class="btn btn-danger btn-lg disabled"> Disabled</button>
<button class="btn btn-success btn-lg active">Active</button> <br> <br>
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