diff --git a/templates/bootstrap/bookdetail.html b/templates/bootstrap/bookdetail.html
index e2d53a4..cbf5397 100644
--- a/templates/bootstrap/bookdetail.html
+++ b/templates/bootstrap/bookdetail.html
@@ -2,7 +2,7 @@
 <div class="col-md-offset-2 col-md-2 col-sm-12">
         {{? it.book.hasCover == 1}}
         <a href="{{=it.book.coverurl}}">
-          <img class="img-responsive" src="{{=it.book.thumbnailurl}}" alt="{{=it.c.i18n.coverAlt}}" />
+          <img class="img-responsive center-block" src="{{=it.book.thumbnailurl}}" alt="{{=it.c.i18n.coverAlt}}" />
         </a>
         {{?}}
 </div>
@@ -29,13 +29,13 @@
 <div class="col-md-2 col-sm-12">
     <div class="btn-group pull-right">
         {{~it.book.datas:data:i}}
-            <a href="{{=data.url}}" class="btn btn-primary btn-sm" role="button">{{=data.format}}</a>
+            <a href="{{=data.url}}" class="btn btn-primary" role="button">{{=data.format}}</a>
             {{? data.mail == 1}}
-            <a id="mailButton" class="btn btn-primary btn-sm" role="button" title="Mail" href="empty.php" onclick="sendToMailAddress (this, {{=data.id}}); return false;">
+            <a id="mailButton" class="btn btn-primary" role="button" title="Mail" href="empty.php" onclick="sendToMailAddress (this, {{=data.id}}); return false;">
             <span class="glyphicon glyphicon-envelope"></span></a>
             {{?}}
             {{? data.readerUrl != ""}}
-            <a title="Reader" class="btn btn-primary btn-sm" role="button" href="{{=data.readerUrl}}" target="blank">
+            <a title="Reader" class="btn btn-primary" role="button" href="{{=data.readerUrl}}" target="blank">
             <span class="glyphicon glyphicon-eye-open"></span></a>
             {{?}}
         {{~}}