Add margin to align pre-paginated pages

src/contents.js

@@ -1070,7 +1070,7 @@ class Contents {
 	 * @param {number} width
 	 * @param {number} height
 	 */
-	fit(width, height){
+	fit(width, height, section){
 		var viewport = this.viewport();
 		var viewportWidth = parseInt(viewport.width);
 		var viewportHeight = parseInt(viewport.height);
@@ -1100,6 +1100,11 @@ class Contents {
 		this.css("background-size", viewportWidth * scale + "px " + viewportHeight * scale + "px");
 
 		this.css("background-color", "transparent");
+		if (section && section.properties.includes("page-spread-left")) {
+			// set margin since scale is weird
+			var marginLeft = width - (viewportWidth * scale);
+			this.css("margin-left", marginLeft + "px");
+		}
 	}
 
 	/**

src/layout.js

@@ -189,11 +189,11 @@ class Layout {
 	 * @param  {Contents} contents
 	 * @return {Promise}
 	 */
-	format(contents){
+	format(contents, section){
 		var formating;
 
 		if (this.name === "pre-paginated") {
-			formating = contents.fit(this.columnWidth, this.height);
+			formating = contents.fit(this.columnWidth, this.height, section);
 		} else if (this._flow === "paginated") {
 			formating = contents.columns(this.width, this.height, this.columnWidth, this.gap);
 		} else { // scrolled

src/managers/views/iframe.js

@@ -149,7 +149,7 @@ class IframeView {
 			.then(function(){
 
 				// apply the layout function to the contents
-				this.layout.format(this.contents);
+				this.layout.format(this.contents, this.section);
 
 				// find and report the writingMode axis
 				let writingMode = this.contents.writingMode();