Currently, I have 4 widgets with different sizes placed within a main div called #box. To center them, I reduced the width to about 60% and set margin left and right to auto. However, when I zoom out in my browser, the widget blocks move more to the left and do not stay centered.
<div id="Box"><!--Start Div Box-->
<div id="TA_certificateOfExcellence580" class="Certificate Certificate-one">
<ul id="Lnnr78SGL0" class="TA_links 4fJwNUzU0uDT">
<li id="phnjh3wZ" class="Yi5zwOy1yHP">
<a target="_blank" href="https://www.tripadvisor.co.za">
<img src="https://www.tripadvisor.co.za/img/cdsi/img2/awards/CoE2014_WidgetAsset-14348-2.png" alt="TripAdvisor"
class="widCOEImg" /></a>
</li>
</ul>
</div>
<div id="TA_certificateOfExcellence654" class="Certificate Certificate-two">
<ul id="FVuBAHp" class="TA_links CPqPZ6">
<li id="dYmcZAj7eGOi" class="FKHiRxci">
<a target="_blank" href="https://www.tripadvisor.co.za">
<img src="https://www.tripadvisor.co.za/img/cdsi/img2/awards/CoE2014_WidgetAsset-14348-2.png" alt="TripAdvisor"
class="widCOEImg" /></a>
</li>
</ul>
</div>
<div id="TA_certificateOfExcellence588" class="Certificate Certificate-three">
<ul id="E4oUIOq5y" class="TA_links JWgIqGH4nEMg">
<li id="R3Oc1SU8Y" class="bXEYi56LVvek">
<a target="_blank" href="https://www.tripadvisor.co.za">
<img src="https://www.tripadvisor.co.za/img/cdsi/img2/awards/CoE2014_WidgetAsset-14348-2.png" alt="TripAdvisor"
class="widCOEImg" /></a>
</li>
</ul>
</div>
<div id="TA_certificateOfExcellence396" class="Certificate Certificate-four-last">
<ul id="ENh9NKezEOIt" class="TA_links j9dirUfR">
<li id="LKMj2Zk" class="Z16i8koQq">
<a target="_blank" href="https://www.tripadvisor.co.za/Attraction_Review-g312578-d2284717-Reviews-Felleng_Day_Tours-Johannesburg_Greater_Johannesburg_Gauteng.html">
<img src="https://www.tripadvisor.co.za/img/cdsi/img2/awards/CoE2015_WidgetAsset-14348-2.png" alt="TripAdvisor"
class="widCOEImg" /></a>
</li>
</ul>
</div>
</div><!--End Div Box-->
#Box
{
background-color:#CCCCCC;
width:60%;
margin-left:auto;
margin-right:auto;
}