diff --git a/src/wp-admin/css/common.css b/src/wp-admin/css/common.css
index e062a471d7150..f91270c22ec71 100644
--- a/src/wp-admin/css/common.css
+++ b/src/wp-admin/css/common.css
@@ -786,7 +786,7 @@ img.emoji {
 }
 
 .stuffbox .hndle {
-	border-bottom: 1px solid #c3c4c7;
+	border-bottom: 1px solid rgba(0, 0, 0, 0.1);
 }
 
 .quicktags {
@@ -2155,7 +2155,7 @@ html.wp-toolbar {
 	display: flex;
 	align-items: center;
 	justify-content: space-between;
-	border-bottom: 1px solid #c3c4c7;
+	border-bottom: 1px solid rgba(0, 0, 0, 0.1);
 }
 
 .postbox-header .hndle {
@@ -2204,8 +2204,10 @@ html.wp-toolbar {
 }
 
 .sortable-placeholder {
-	border: 1px dashed #c3c4c7;
+	border: 2px solid var(--wp-admin-theme-color);
+	border-radius: 8px;
 	margin-bottom: 20px;
+	background: rgba(var(--wp-admin-theme-color--rgb), 0.04);
 }
 
 .postbox,
@@ -2213,10 +2215,13 @@ html.wp-toolbar {
 	margin-bottom: 20px;
 	padding: 0;
 	line-height: 1;
+	background: #ffffff;
+	border: 1px solid rgba(0, 0, 0, 0.1);
+	border-radius: 0;
 }
 
-.postbox.closed {
-	border-bottom: 0;
+.postbox.closed .postbox-header {
+	border-bottom: none;
 }
 
 /* user-select is not a part of the CSS standard - may change behavior in the future */
@@ -2227,7 +2232,7 @@ html.wp-toolbar {
 }
 
 .postbox .inside {
-	padding: 0 12px 12px;
+	padding: 16px;
 	line-height: 1.4;
 	font-size: 13px;
 }
@@ -2240,7 +2245,7 @@ html.wp-toolbar {
 }
 
 .postbox .inside {
-	margin: 11px 0;
+	margin: 0;
 	position: relative;
 }
 
@@ -2421,7 +2426,7 @@ h1.nav-tab-wrapper, /* Back-compat for pre-4.4 */
 .metabox-holder h3.hndle, /* Back-compat for pre-4.4 */
 .metabox-holder h2.hndle {
 	font-size: 14px;
-	padding: 8px 12px;
+	padding: 16px;
 	margin: 0;
 	line-height: 1.4;
 }
diff --git a/src/wp-admin/css/dashboard.css b/src/wp-admin/css/dashboard.css
index 64aa30dbedeac..56732b9641a14 100644
--- a/src/wp-admin/css/dashboard.css
+++ b/src/wp-admin/css/dashboard.css
@@ -40,7 +40,15 @@
 
 #dashboard-widgets-wrap {
 	overflow: hidden;
-	margin: 0 -8px;
+	margin: 0 -4px;
+}
+
+#dashboard-widgets .postbox {
+	border-radius: 8px;
+}
+
+#dashboard-widgets .postbox-header .hndle {
+	padding: 12px 16px;
 }
 
 #dashboard-widgets .postbox .inside {
@@ -50,20 +58,31 @@
 #dashboard-widgets .meta-box-sortables {
 	display: flow-root; /* avoid margin collapsing between parent and first/last child elements */
 	/* Required min-height to make the jQuery UI Sortable drop zone work. */
-	min-height: 100px;
-	margin: 0 8px 20px;
+	min-height: 0;
+	margin: 0 8px 0 0;
+	padding: 4px;
+}
+
+#dashboard-widgets .meta-box-sortables:not(:empty) {
+	margin-bottom: 16px;
 }
 
 #dashboard-widgets .postbox-container .empty-container {
-	outline: 3px dashed #c3c4c7;
+	border: 2px dashed rgba(0, 0, 0, 0.15);
+	border-radius: 8px;
 	height: 250px;
 }
 
-/* Only highlight drop zones when dragging and only in the 2 columns layout. */
+/* Only highlight drop zones when dragging. */
 .is-dragging-metaboxes #dashboard-widgets .meta-box-sortables {
-	outline: 3px dashed #646970;
-	/* Prevent margin on the child from collapsing with margin on the parent. */
-	display: flow-root;
+	border-radius: 8px;
+	background: rgba(var(--wp-admin-theme-color--rgb), 0.04);
+	min-height: 100px;
+}
+
+.is-dragging-metaboxes #dashboard-widgets .postbox-container .empty-container {
+	border: 2px dashed rgba(0, 0, 0, 0.15);
+	background: rgba(0, 0, 0, 0.01);
 }
 
 #dashboard-widgets .postbox-container .empty-container:after {
@@ -121,6 +140,8 @@
 	overflow: auto;
 	margin: 16px 0;
 	background-color: #151515;
+	border: 1px solid rgba(0, 0, 0, 0.1);
+	border-radius: 8px;
 	font-size: 14px;
 	line-height: 1.3;
 	clear: both;
@@ -259,11 +280,11 @@
 	clear: both;
 	display: grid;
 	z-index: 1;
-	padding: 48px;
+	padding: 24px;
 	grid-template-columns: repeat(3, 1fr);
 	gap: 32px;
 	align-self: flex-end;
-	background: #fff;
+	background: #ffffff;
 }
 
 [class*="welcome-panel-icon"] {
@@ -704,7 +725,7 @@ body #dashboard-widgets .postbox form .submit {
 }
 
 #dashboard_right_now .main {
-	padding: 0 12px 11px;
+	padding: 16px 16px 11px;
 }
 
 #dashboard_right_now .main p {
@@ -892,7 +913,7 @@ body #dashboard-widgets .postbox form .submit {
 
 #dashboard_activity .inside {
 	margin: 0;
-	padding-bottom: 0;
+	padding: 0 12px;
 }
 
 #dashboard_activity .no-activity {
@@ -1298,7 +1319,7 @@ a.rsswidget {
 
 	#dashboard-widgets #postbox-container-3 .empty-container,
 	#dashboard-widgets #postbox-container-4 .empty-container {
-		outline: none;
+		border: none;
 		height: 0;
 		min-height: 0;
 		margin-bottom: 0;
@@ -1314,7 +1335,7 @@ a.rsswidget {
 	}
 
 	#wpbody #dashboard-widgets .metabox-holder.columns-1 .postbox-container .empty-container {
-		outline: none;
+		border: none;
 		height: 0;
 		min-height: 0;
 		margin-bottom: 0;
@@ -1352,7 +1373,7 @@ a.rsswidget {
 	}
 
 	#dashboard-widgets #postbox-container-4 .empty-container {
-		outline: none;
+		border: none;
 		height: 0;
 		min-height: 0;
 		margin-bottom: 0;
diff --git a/src/wp-admin/css/edit.css b/src/wp-admin/css/edit.css
index 7e4110a8c569e..b442e348e5e38 100644
--- a/src/wp-admin/css/edit.css
+++ b/src/wp-admin/css/edit.css
@@ -5,6 +5,7 @@
 
 #poststuff #post-body {
 	padding: 0;
+	margin: 0 -4px;
 }
 
 #poststuff .postbox-container {
@@ -167,11 +168,14 @@ body.post-type-wp_navigation .inline-edit-status {
 
 /* Post Screen */
 
+.metabox-holder .postbox-container .meta-box-sortables {
+	padding: 4px;
+}
+
 /* Only highlight drop zones when dragging and only in the 2 columns layout. */
 .is-dragging-metaboxes .metabox-holder .postbox-container .meta-box-sortables {
-	outline: 3px dashed #646970;
-	/* Prevent margin on the child from collapsing with margin on the parent. */
-	display: flow-root;
+	border-radius: 8px;
+	background: rgba(var(--wp-admin-theme-color--rgb), 0.04);
 	/*
 	 * This min-height is meant to limit jumpiness while dragging. It's equivalent
 	 * to the minimum height of the sortable-placeholder which is given by the height
@@ -1770,7 +1774,8 @@ table.links-table {
 	}
 
 	.is-dragging-metaboxes.post-type-attachment #post-body .meta-box-sortables {
-		outline: none;
+		border: none;
+		background: transparent;
 		min-height: 0;
 		margin-bottom: 0;
 	}
diff --git a/src/wp-admin/css/forms.css b/src/wp-admin/css/forms.css
index 719be1aad9ba1..e3727f810933e 100644
--- a/src/wp-admin/css/forms.css
+++ b/src/wp-admin/css/forms.css
@@ -1047,12 +1047,12 @@ table.form-table td .updated p {
 .card {
 	position: relative;
 	margin-top: 20px;
-	padding: 0.7em 2em 1em;
+	padding: 16px 24px;
 	min-width: 255px;
 	max-width: 520px;
-	border: 1px solid #c3c4c7;
-	box-shadow: 0 1px 1px rgba(0, 0, 0, 0.04);
-	background: #fff;
+	border: 1px solid rgba(0, 0, 0, 0.1);
+	border-radius: 8px;
+	background: #ffffff;
 	box-sizing: border-box;
 }
 
diff --git a/src/wp-admin/css/list-tables.css b/src/wp-admin/css/list-tables.css
index 80e652003a33c..9bb79349b6ade 100644
--- a/src/wp-admin/css/list-tables.css
+++ b/src/wp-admin/css/list-tables.css
@@ -1487,9 +1487,11 @@ ul.cat-checklist input[name="post_category[]"]:indeterminate::before {
 	margin: 0 8px 16px;
 	width: 48.5%;
 	width: calc( 50% - 8px );
-	background-color: #fff;
-	border: 1px solid #dcdcde;
+	background-color: #ffffff;
+	border: 1px solid rgba(0, 0, 0, 0.1);
+	border-radius: 8px;
 	box-sizing: border-box;
+	overflow: hidden;
 }
 
 .plugin-card:nth-child(odd) {
@@ -1553,7 +1555,7 @@ ul.cat-checklist input[name="post_category[]"]:indeterminate::before {
 
 .plugin-card-top {
 	position: relative;
-	padding: 20px 20px 10px;
+	padding: 16px;
 	min-height: 135px;
 }
 
@@ -1668,9 +1670,9 @@ div.action-links,
 
 .plugin-card-bottom {
 	clear: both;
-	padding: 12px 20px;
+	padding: 16px;
 	background-color: #f6f7f7;
-	border-top: 1px solid #dcdcde;
+	border-top: 1px solid rgba(0, 0, 0, 0.1);
 	overflow: hidden;
 }
 
diff --git a/src/wp-admin/css/themes.css b/src/wp-admin/css/themes.css
index ea62a09cf1ed1..0ee20cc4d6c8f 100644
--- a/src/wp-admin/css/themes.css
+++ b/src/wp-admin/css/themes.css
@@ -64,9 +64,11 @@ body.js .theme-browser.search-loading {
 	margin: 0 4% 4% 0;
 	position: relative;
 	width: 30.6%;
-	border: 1px solid #dcdcde;
-	box-shadow: 0 1px 1px -1px rgba(0, 0, 0, 0.1);
+	background: #ffffff;
+	border: 1px solid rgba(0, 0, 0, 0.1);
+	border-radius: 8px;
 	box-sizing: border-box;
+	overflow: hidden;
 }
 
 .theme-browser .theme:nth-child(3n) {
@@ -83,13 +85,12 @@ body.js .theme-browser.search-loading {
 	font-weight: 600;
 	height: 18px;
 	margin: 0;
-	padding: 15px;
-	box-shadow: inset 0 1px 0 rgba(0, 0, 0, 0.1);
+	padding: 16px;
+	border-top: 1px solid rgba(0, 0, 0, 0.1);
 	overflow: hidden;
 	white-space: nowrap;
 	text-overflow: ellipsis;
-	background: #fff;
-	background: rgba(255, 255, 255, 0.65);
+	background: #ffffff;
 }
 
 /* Activate and Customize buttons, shown on hover and focus */
@@ -271,8 +272,9 @@ body.js .theme-browser.search-loading {
  * Add new theme
  */
 .theme-browser .theme.add-new-theme {
+	background: transparent;
 	border: none;
-	box-shadow: none;
+	overflow: visible;
 }
 
 .theme-browser .theme.add-new-theme a {
@@ -348,8 +350,8 @@ body.js .theme-browser.search-loading {
 
 .theme-browser .theme.add-new-theme .theme-name {
 	background: none;
+	border: none;
 	text-align: center;
-	box-shadow: none;
 	font-weight: 400;
 	position: relative;
 	top: 0;