Improve book list buttons in mobile view

front/src/BookListElement.vue

@@ -143,6 +143,7 @@ async function importInventaireEdition(inventaireid) {
       </div>
     </div>
     <div v-if="id && id != 0" class="column is-narrow">
+      <div class="buttons">
         <button @click="onUserBookWantRead" class="button is-large verticalbutton">
           <span class="icon" :title="$t('booklistelement.wantread')">
             <b-icon-eye-fill v-if="isWantRead" />
@@ -163,6 +164,7 @@ async function importInventaireEdition(inventaireid) {
         </button>
       </div>
     </div>
+  </div>
 </template>
 
 <style scoped>
@@ -183,6 +185,10 @@ img {
   transition: ease-in-out 0.02s;
 }
 
+.buttons {
+  display: block;
+}
+
 .verticalbutton {
   display: block;
 }
@@ -194,4 +200,12 @@ img {
 .no-margin {
   margin: 0px;
 }
+
+@media (max-width: 1024px) {
+  .buttons {
+    display: flex;
+    justify-content: center;
+    align-items: center;
+  }
+}
 </style>