Adjust layout sizing for better flexibility and spacing

Removed `max-width` constraints from `body.resizing` to allow more flexible layouts. Updated `width` properties in `body.resizing` and `.pdf-frame` to slightly increase their sizes, improving space utilization. These changes refine the design to better align with the intended user interface behavior.

EnvelopeGenerator.ReceiverUI/wwwroot/css/envelope-viewer.css

@@ -227,7 +227,6 @@ body.resizing {
     border: 1px solid rgba(126, 34, 206, 0.15);
     flex-shrink: 0;
     width: 95%;
-    max-width: 1400px;
 }
 
 .pdf-toolbar__section {
@@ -471,8 +470,7 @@ body.resizing {
     overflow: hidden;
     position: relative;
     flex: 1;
-    width: 90%;
-    max-width: 1200px;
+    width: 95%;
     display: flex;
     flex-direction: row;
     align-items: stretch;
@@ -649,7 +647,7 @@ body.resizing {
 
 .pdf-frame {
     border-radius: 12px;
-    width: 95%;
+    width: 98%;
     flex-direction: column;
 }