STYLE: adjust sponsor logo sizes and update POSTECH logo

Author: hyeondo-jang

index.html

@@ -132,7 +132,8 @@
             flex-wrap: wrap;
             align-items: center;
             justify-content: center;
-            gap: 20px;
+            column-gap: 20px;
+            row-gap: 4px;
             margin-top: 20px;
             background: #fff;
             border-radius: 10px;
@@ -272,7 +273,7 @@ <h3>Acknowledgements</h3>
             <div class="sponsor-card"><img src="logo/samsung_logo.svg" alt="Samsung"></div>
             <div class="sponsor-card"><img src="logo/naver_logo.svg" alt="Naver" style="width:56px;height:56px;"></div>
             <div class="sponsor-card"><img src="logo/intel_logo.svg" alt="Intel" style="width:42px;height:42px;"></div>
-            <div class="sponsor-card"><img src="logo/postech_logo.png" alt="POSTECH" style="width:84px;height:84px;"></div>
+            <div class="sponsor-card"><img src="logo/postech_logo2.jpg" alt="POSTECH" style="width:52px;height:52px;"></div>
             <div class="sponsor-card"><img src="logo/yonsei_logo.png" alt="Yonsei" style="width:38px;height:38px;"></div>
         </div>
     </main>