```css <button class="btn btn-default">default</button> <button class="btn btn-info">info</button> <button class="btn btn-primary">primary</button> <button class="btn btn-warning">warn</button> <button class="btn btn-success">success</button> <button class="btn btn-danger">danger</button> <button class="btn btn-inverse">inverse</button> ```  ``` <button class="btn btn-danger" disabled>提交</button> ```