remove unused classes

app/components/BookBuilder/BookBuilderModal.jsx

@@ -23,7 +23,7 @@ export class BookBuilderModal extends React.Component {
     const modalSize = size || null
     let modalBodyText = ''
 
-    const success = successAction ? <a className='modal-button add-chapter bb-modal-act'
+    const success = successAction ? <a className='modal-button bb-modal-act'
       onClick={successAction}>
       { successText }
     </a> : null
@@ -82,9 +82,9 @@ export class BookBuilderModal extends React.Component {
         </Modal.Body>
 
         <Modal.Footer>
-          <div className='buttons-container'>
+          <div className='modal-buttons-container'>
 
-            <a className='modal-button discard-chapter bb-modal-cancel'
+            <a className='modal-button modal-discard bb-modal-cancel'
               onClick={toggle}>
               Cancel
             </a>

app/components/BookBuilder/BookList.jsx

@@ -75,7 +75,7 @@ export class BookList extends React.Component {
           </Modal.Body>
 
           <Modal.Footer>
-            <a className='modal-button discard-chapter'
+            <a className='modal-button modal-discard'
               onClick={this._toggleModal}>
               Close
             </a>