From e117993b7f8f8ecf6f49ad171bc4d10121131c63 Mon Sep 17 00:00:00 2001
From: Riad Benguella <benguella@gmail.com>
Date: Wed, 23 Jan 2019 08:48:04 +0100
Subject: [PATCH] Fix HTML preview for themes applying global margins (#13416)

---
 packages/block-library/src/html/edit.js | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/packages/block-library/src/html/edit.js b/packages/block-library/src/html/edit.js
index d9bbe4e07211f3..44aa79544415b5 100644
--- a/packages/block-library/src/html/edit.js
+++ b/packages/block-library/src/html/edit.js
@@ -20,7 +20,22 @@ class HTMLEdit extends Component {
 
 	componentDidMount() {
 		const { styles } = this.props;
-		this.setState( { styles: transformStyles( styles ) } );
+
+		// Default styles used to unset some of the styles
+		// that might be inherited from the editor style.
+		const defaultStyles = `
+			html,body,:root {
+				margin: 0 !important;
+				padding: 0 !important;
+				overflow: visible !important;
+				min-height: auto !important;
+			}
+		`;
+
+		this.setState( { styles: [
+			defaultStyles,
+			...transformStyles( styles ),
+		] } );
 	}
 
 	switchToPreview() {