btn disabled bootstrap 4 code example
Example: bootstrap disabled button
<button type="button" class="btn btn-lg btn-primary" disabled>Primary button</button>
<button type="button" class="btn btn-secondary btn-lg" disabled>Button</button>
<button type="button" class="btn btn-lg btn-primary" disabled>Primary button</button>
<button type="button" class="btn btn-secondary btn-lg" disabled>Button</button>