add some padding for abstract button and center content

components/content/ArticleDoi.vue

@@ -44,13 +44,14 @@ const articleAbstract = computed(() => {
     </template> -->
     <v-card flat color="transparent" density="compact" class="my-0 article-ref">
       <v-card-item density="compact" class="pa-0">
-        <v-toolbar class="py-0 d-flex align-start article-toolbar" color="transparent"  :height="20">
+        <v-toolbar class="py-0 d-flex align-start article-toolbar" color="transparent" :height="20">
           <v-toolbar-title class="font-weight-bold ml-0">{{ articleTitle }}</v-toolbar-title>
+
           <v-btn v-if="articleAbstract" size="x-small" variant="plain" color="primary"
-            :append-icon="show ? 'mdi-chevron-up' : 'mdi-chevron-down'" class="px-0"
+            :append-icon="show ? 'mdi-chevron-up' : 'mdi-chevron-down'" class="px-1 align-center"
             @click.stop.prevent="show = !show">Abstract</v-btn>
         </v-toolbar>
-          <!-- <v-card-title class="py-0"><span class="font-weight-bold">{{
+        <!-- <v-card-title class="py-0"><span class="font-weight-bold">{{
             articleTitle
           }}</span></v-card-title> -->
         <v-card-subtitle class="py-0">
@@ -86,12 +87,12 @@ const articleAbstract = computed(() => {
 .article-ref .v-card-item button.v-btn span {
   font-size: 0.8rem !important;
 }
-.article-toolbar .v-toolbar-title  {
+
+.article-toolbar .v-toolbar-title {
   font-size: 0.9rem !important;
 }
 
 .article-toolbar div.v-toolbar__content * {
   align-items: flex-start;
 }
-
 </style>
\ No newline at end of file