feat : 반응형 버튼 수정

src/css/common.css

@@ -609,7 +609,10 @@ body{overflow-x:hidden;}
   .about-tech-cards { grid-template-columns: 1fr 1fr; }
   .about-cta-section { padding: 80px 24px; }
   .about-cta-title { font-size: 28px; }
-  .about-cta-buttons { flex-direction: column; align-items: center; }
+    .about-cta-btn { width: 100%; max-width: 280px; justify-content: center; }
+
+    .about-cta-buttons { flex-direction: column; align-items: center; width: 100%; }
+
 }
 
 @keyframes about-cta-move {