Ghost/ghost/admin/app/templates/components/modals/delete-theme.hbs

<header class="modal-header" data-test-delete-theme-modal>
    <h1>Are you sure you want to delete this</h1>
</header>
<a class="close icon-x" href="" title="Close" {{action "closeModal"}}><span class="hidden">Close</span></a>

<div class="modal-body">
    <p>You're about to delete "<strong>{{theme.label}}</strong>". This is permanent! We warned you, k? Maybe <a href="#" {{action download}}>Download your theme before continuing</a></p>
</div>

<div class="modal-footer">
    <button {{action "closeModal"}} class="gh-btn"><span>Cancel</span></button>
    {{#gh-task-button task=deleteTheme class="gh-btn gh-btn-red"}}<span>Delete</span>{{/gh-task-button}}
</div>