HTML

bootstarp btn colors

<button type="button" class="btn btn-primary">Blue</button>
<button type="button" class="btn btn-secondary">Grey</button>
<button type="button" class="btn btn-success">Green</button>
<button type="button" class="btn btn-danger">Red</button>
<button type="button" class="btn btn-warning">Yellow</button>
<button type="button" class="btn btn-info">Ligth blue</button>
<button type="button" class="btn btn-light">White</button>
<button type="button" class="btn btn-dark">Black</button>

<button type="button" class="btn btn-link">White with blue text</button>

custom color bootstrap buttonm

.btn-primary, .btn-primary:hover, .btn-primary:active, .btn-primary:visited {
    background-color: #8064A2 !important;
}

bootstrap btn colors

<!-- Bootstrap v5.0 -->

<button type="button" class="btn btn-primary">Primary</button>
<button type="button" class="btn btn-secondary">Secondary</button>
<button type="button" class="btn btn-success">Success</button>
<button type="button" class="btn btn-danger">Danger</button>
<button type="button" class="btn btn-warning">Warning</button>
<button type="button" class="btn btn-info">Info</button>
<button type="button" class="btn btn-light">Light</button>
<button type="button" class="btn btn-dark">Dark</button>

<button type="button" class="btn btn-link">Link</button>

Bootstrap custom button color

.btn-primary, .btn-primary:hover, .btn-primary:active, .btn-primary:visited {
    background-color: #8064A2;
}