diff --git a/src/css/map-view.css b/src/css/map-view.css
index 1812de6fe..483f7de6c 100644
--- a/src/css/map-view.css
+++ b/src/css/map-view.css
@@ -180,7 +180,7 @@
   --headerHeight: 80px;
   position: relative;
   height: 100%;
-  min-height: calc(100vh - var(--headerHeight));
+  min-height: 100%;
   width: 100%;
   display: grid;
   box-sizing: border-box;
@@ -229,6 +229,8 @@
   top: 0;
   left: 0;
   height: 100%;
+  overflow: hidden;
+  width: min-content;
   /* required to be placed above map widget in firefox: */
   z-index: 1;
 }
@@ -395,6 +397,7 @@ represents 1 unit of the given distance measurement. */
   class .toolbar, is not hidden so that the links (tabs) are still visible when the
   toolbar is closed */
   display: none;
+  overflow: hidden;
 }
 
 .toolbar--open .toolbar__all-content {
@@ -408,10 +411,12 @@ represents 1 unit of the given distance measurement. */
   justify-content: center;
   /* hide unless the content section is active */
   display: none;
+  overflow: auto;
 }
 
 .toolbar__content--active {
   padding-top: 1rem;
+  padding-right: 1rem;
   display: flex;
 }
 
diff --git a/src/css/metacatui-common.css b/src/css/metacatui-common.css
index f786db5ce..d70ae04f3 100644
--- a/src/css/metacatui-common.css
+++ b/src/css/metacatui-common.css
@@ -4875,6 +4875,12 @@ i.toc-sub-item {
 * Portals
 ********************************************/
 
+.PortalView {
+  height: 100%;
+  display: grid;
+  grid-template-rows: 40px 0px 100fr 0px;
+}
+
 .portal-view{
   width: calc(100% + 80px);
   margin-left: -40px;
@@ -5458,6 +5464,7 @@ i.toc-sub-item {
 /** The Portal Visualization View **/
 .portal-viz-section-view{
   background-color: black;
+  height: 100%;
 }
 .portal-viz-section-view iframe{
   box-sizing: border-box;
diff --git a/src/js/themes/knb/css/metacatui.css b/src/js/themes/knb/css/metacatui.css
index 89862093d..729ee42d2 100644
--- a/src/js/themes/knb/css/metacatui.css
+++ b/src/js/themes/knb/css/metacatui.css
@@ -177,6 +177,11 @@
 
 /* Portal & Editor (minimal header common to both views)
 -------------------------------------------------- */
+.PortalView {
+  /* Rows template differs from metacatui-common.css due to hiding #HeaderContainer. */
+  grid-template-rows: 40px 100fr;
+}
+
 #Navbar .navbar-inner:before, .navbar-inner:after {
 	display: none;
 }