diff --git a/index.html b/index.html
index e850622..6510838 100644
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+++ b/index.html
@@ -36,7 +36,12 @@
 							<article class="col-6 col-12-xsmall work-item">
 								<a href="images/pki.jpg" class="image fit thumb"><img src="images/pki.jpg" alt="" /></a>
 								<h3><a href="https://pki.zhanganjun.com">PKI Services</a></h3>
-								<p>PKI system supports the generation, issuance, distribution, revocation, administration, and management of public/private cryptographic keys that are contained in CA-signed X.509 Certificates.</p>
+								<p>Zhang Anjun PKI Services was established to support the generation, issuance, distribution, revocation, administration, and management of public/private cryptographic keys that are contained in CA-signed X.509 Certificates.</p>
+							</article>
+							<article class="col-6 col-12-xsmall work-item">
+								<a href="images/next_permutation.jpg" class="image fit thumb"><img src="images/next_permutation.jpg" alt="" /></a>
+								<h3><a href="https://github.com/CitizenBeta/Next-Permutation">Next Permutation</a></h3>
+								<p>A Python script to compute the next smaller and larger permutations of a given number (If you cannot access GitHub, <a href="https://repo.zhanganjun.com/Next-Permutation">click here</a>).</p>
 							</article>
 							<article class="col-6 col-12-xsmall work-item">
 								<a href="images/calendar_generator.jpg" class="image fit thumb"><img src="images/calendar_generator.jpg" alt="" /></a>
@@ -48,28 +53,19 @@
 								<h3><a href="https://github.com/CitizenBeta/Connect4">Connect 4</a></h3>
 								<p>A Python implementation of the classic text-based Connect 4 game (If you cannot access GitHub, <a href="https://repo.zhanganjun.com/Connect4">click here</a>).</p>
 							</article>
-							<article class="col-6 col-12-xsmall work-item">
-								<a href="images/next_permutation.jpg" class="image fit thumb"><img src="images/next_permutation.jpg" alt="" /></a>
-								<h3><a href="https://github.com/CitizenBeta/Next-Permutation">Next Permutation</a></h3>
-								<p>A Python script to compute the next smaller and larger permutations of a given number (If you cannot access GitHub, <a href="https://repo.zhanganjun.com/Next-Permutation">click here</a>).</p>
-							</article>
 						</div>
 					</section>
 
 				<!-- Three -->
 					<section id="three">
-						
-						
 						<section>
 							<h2>Object Identifier</h2>
 							<p>Object Identifier (OID) is an identifier mechanism standardized by the International Telecommunication Union (ITU) and ISO/IEC for naming any object, concept, or "thing" with a globally unambiguous persistent name.</p>
-							<p>The Internet Assigned Numbers Authority (IANA) has assigned me an arc.</p>
-							<p>The OID prefix is <b>1.3.6.1.4.1.63420</b>.</p>
+							<p>I have been assigned the OID arc <b>1.3.6.1.4.1.63420</b> by the Internet Assigned Numbers Authority (IANA).</p>
 							<ul class="actions">
 								<li><a href="https://repo.zhanganjun.com/OID/OID_Assignment_v1_0.pdf" class="button icon solid fa-download">OID Assignment PDF</a></li>
 							</ul>
 						</section>
-						
 					</section>
 
 		<!-- Footer -->
@@ -83,7 +79,7 @@
 					</ul>
 					<ul class="copyright">
 						<li>&copy; <span id=year><script>document.getElementById("year").innerHTML=(new Date).getFullYear()</script></span> Zhang Anjun. All rights reserved.</li>
-						<li><a href="https://github.com/CitizenBeta/Homepage/releases/tag/v3.11">v3.11</a></li>
+						<li><a href="https://github.com/CitizenBeta/Homepage/releases/tag/v3.11.1">v3.11.1</a></li>
 						<li><a href="https://zaj.statuspage.io/">System Status</a></li>
 						<li><img src="https://static.zhanganjun.com/common/beian.png" style="width:16px;"/><a href="https://beian.mps.gov.cn/#/query/webSearch?code=11010802045392" rel="noreferrer" target="_blank">京公网安备11010802045392号</a></li>
 						<li><a href="https://beian.miit.gov.cn" target="_blank">京ICP备2025105392号-2</a></li>