diff --git a/.gitignore b/.gitignore
index 3f89ec1..02ccb43 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@
 .dropbox
 nbproject
 local
-
+.DS_Store
+.claude/
diff --git a/visualcube.php b/visualcube.php
index a1e121a..a32642d 100644
--- a/visualcube.php
+++ b/visualcube.php
@@ -493,10 +493,18 @@
 		$sw = 0;
 
 		// Viewport
-		$ox = -0.9;
-		$oy = -0.9;
-		$vw = 1.8;
-		$vh = 1.8;
+		$default_port = 1.8;
+		$vw = $default_port;
+		$vh = $default_port;
+		$ox = -$vw / 2;
+		$oy = -$vh / 2;
+		// Allow user to override viewport size via 'port' parameter
+		if (array_key_exists('port', $_REQUEST) && is_numeric($_REQUEST['port'])) {
+		    $vw = floatval($_REQUEST['port']);
+		    $vh = $vw;
+		    $ox = -$vw / 2;
+		    $oy = -$vh / 2;
+		}
 
 		// ------------------[ 3D Cube Generator ]-----------------------
 
diff --git a/visualcube_api.php b/visualcube_api.php
index dd8b318..86476ef 100644
--- a/visualcube_api.php
+++ b/visualcube_api.php
@@ -259,6 +259,8 @@ function setCookie(cname, value){
 					<td>Setting this value causes the facelets to be rendered with transparency.</td></tr>
 				<tr><td><em>dist</em></td><td>Projection Distance</td><td>1 to 100</td><td><?php echo $DEFAULTS['dist']; ?></td>
 					<td>Controls the distance of the cube from the perspective of the viewer.</td></tr>
+             			<tr><td><em>port</em></td><td>Viewport Size</td><td>Any number (e.g., 1.6)</td><td>1.8</td>
+					<td>Controls the size of the viewport, effectively zooming in or out. Smaller numbers zoom in, reducing the border. 1.5 works well with view=plan</td></tr>
 				<tr><th colspan="5">Added Features</th></tr>
 				<tr><td><em>arw</em></td><td>Arrow Definition</td>
 					<td>Comma separated list in the form:<br/><br/>