Fix Save Roll button centering in dice popup

- Added margin-left and margin-right auto to center the button in desktop view
- Button now properly centers within the popup window when max-width is applied

style.css

@@ -639,7 +639,7 @@ body:has(.rpg-panel.rpg-position-left) #sheld {
 }
 
 .rpg-inventory-items {
-    font-size: clamp(0.4vw, 0.5vw, 0.6vw);
+    font-size: clamp(0.7vw, 0.5vw, 0.6vw);
     color: var(--rpg-text);
     line-height: 1.3;
     overflow-y: auto;
@@ -2542,6 +2542,8 @@ body:has(.rpg-panel.rpg-position-left) #sheld {
 
     .rpg-dice-save-btn {
         max-width: 200px;
+        margin-left: auto;
+        margin-right: auto;
     }
 }