diff --git a/tabs/calibration.html b/tabs/calibration.html
index 69a005632..3305944e1 100755
--- a/tabs/calibration.html
+++ b/tabs/calibration.html
@@ -3,7 +3,7 @@
         <!-- should be the first DIV on each tab -->
         <div class="cf_column full spacerbottom">
             <div class="tab_title" data-i18n="tabCalibration">Calibration</div>
-            <div class="cf_column threefourth_left">
+            <div class="cf_column left">
                 <div class="spacer_right">
                     <div class="gui_box grey">
                         <div class="gui_box_titlebar">
@@ -176,4 +176,4 @@ <h1 class="modal__title modal__title--center" data-i18n="accCalibrationProcessin
         <h1 class="modal__title modal__title--center" data-i18n="accCalibrationProcessing"></h1>
         <div id="modal-opflow-countdown" class="modal__text"></div>
     </div>
-</div>
\ No newline at end of file
+</div>