MOBILE-2782 wiki: Fix empty and tabs styles

src/addon/mod/wiki/components/index/addon-mod-wiki-index.html

@@ -47,7 +47,7 @@
 
                     <article [ngClass]="{'addon-mod_wiki-noedit': !canEdit}">
                         <core-format-text *ngIf="pageContent" [component]="component" [componentId]="componentId" [text]="pageContent"></core-format-text>
-                        <core-empty-box *ngIf="!pageContent" icon="document" [message]="'addon.mod_wiki.nocontent' | translate"></core-empty-box>
+                        <core-empty-box *ngIf="!pageContent" icon="document" [message]="'addon.mod_wiki.nocontent' | translate" [inline]="true"></core-empty-box>
                     </article>
                 </div>
             </ng-template>

src/components/tabs/tabs.scss

@@ -30,6 +30,10 @@ ion-app.app-root .core-tabs-bar {
             line-height: 1.2em;
         }
 
+        ion-icon {
+            @include margin(null, 5px, null, null);
+        }
+
         ion-badge.tab-badge {
             position: relative;
             @include position(auto, auto, auto, auto);

src/theme/variables.scss

@@ -400,6 +400,27 @@ $core-question-state-incorrect-color: $red-light !default;
     }
 }
 
+@mixin core-headings() {
+  h1 {
+    font-size: 3rem;
+  }
+  h2 {
+    font-size: 2.8rem;
+  }
+  h3 {
+    font-size: 2.6rem;
+  }
+  h4 {
+    font-size: 2.2rem;
+  }
+  h5 {
+    font-size: 1.8rem;
+  }
+  h6 {
+    font-size: 1.4rem;
+  }
+}
+
 // Font Awesome
 $fa-font-path: $font-path;
 @import "font-awesome";