diff --git a/src/defaultCss/defaultV2Css.ts b/src/defaultCss/defaultV2Css.ts
index 83949e9c86..6d0e89ed6b 100644
--- a/src/defaultCss/defaultV2Css.ts
+++ b/src/defaultCss/defaultV2Css.ts
@@ -20,7 +20,6 @@ export var defaultV2Css = {
   rootWrapperFixed: "sd-root-modern__wrapper--fixed",
   rootBackgroundImage: "sd-root_background-image",
   rootBackgroundImageFixed: "sd-root_background-image--fixed",
-  rootForm: "sd-root_form",
   container: "sd-container-modern",
   header: "sd-title sd-container-modern__title",
   bodyContainer: "sv-components-row",
diff --git a/src/defaultV2-theme/blocks/sd-body.scss b/src/defaultV2-theme/blocks/sd-body.scss
index adf25fe501..dd0dec1ecc 100644
--- a/src/defaultV2-theme/blocks/sd-body.scss
+++ b/src/defaultV2-theme/blocks/sd-body.scss
@@ -185,6 +185,6 @@
   left: 0;
   right: 0;
 }
-.sd-root-modern--full-container .sd-root_background-image.sd-root_background-image--fixed {
+.sd-root-modern--full-container.sd-root-modern__wrapper--fixed .sd-root_background-image {
   right: 12px;
 }
diff --git a/src/knockout/templates/index.html b/src/knockout/templates/index.html
index 6be70d2f7a..931ea19cb8 100644
--- a/src/knockout/templates/index.html
+++ b/src/knockout/templates/index.html
@@ -7,9 +7,9 @@
   <div data-bind="css: rootCss, elementStyle: themeVariables">
     <div data-bind="css: wrapperFormCss">
       <!-- ko if: !!renderBackgroundImage -->
-      <div data-bind="css: backgroundImageCss, elementStyle: backgroundImageStyle"></div>
+      <div data-bind="css: css.rootBackgroundImage, elementStyle: backgroundImageStyle"></div>
       <!-- /ko -->
-      <form data-bind="css: css.rootForm" onsubmit="return false;">
+      <form onsubmit="return false;">
           <div class="sv_custom_header" data-bind="visible: !hasLogo"></div>
           <div data-bind="css: containerCss">
               <!-- ko template: { name: koTitleTemplate, afterRender: koAfterRenderHeader } -->
diff --git a/src/react/reactSurvey.tsx b/src/react/reactSurvey.tsx
index 2370e059fe..34b9a2659c 100644
--- a/src/react/reactSurvey.tsx
+++ b/src/react/reactSurvey.tsx
@@ -95,7 +95,7 @@ export class Survey extends SurveyElementBase<any, any>
     } else {
       renderResult = this.renderSurvey();
     }
-    const backgroundImage = !!this.survey.backgroundImage ? <div className={this.survey.backgroundImageCss} style={this.survey.backgroundImageStyle}></div> : null;
+    const backgroundImage = !!this.survey.backgroundImage ? <div className={this.css.rootBackgroundImage} style={this.survey.backgroundImageStyle}></div> : null;
     const header: JSX.Element = <SurveyHeader survey={this.survey}></SurveyHeader>;
     const onSubmit = function (event: React.FormEvent<HTMLFormElement>) {
       event.preventDefault();
@@ -111,7 +111,7 @@ export class Survey extends SurveyElementBase<any, any>
       <div id={this.rootNodeId} ref={this.rootRef} className={cssClasses} style={this.survey.themeVariables}>
         <div className={this.survey.wrapperFormCss}>
           {!!backgroundImage ? backgroundImage: null}
-          <form className={this.css.rootForm} onSubmit={onSubmit}>
+          <form onSubmit={onSubmit}>
             {customHeader}
             <div className={this.css.container}>
               {header}
diff --git a/src/survey.ts b/src/survey.ts
index 8783377f27..09af04d0a0 100644
--- a/src/survey.ts
+++ b/src/survey.ts
@@ -1090,7 +1090,6 @@ export class SurveyModel extends SurveyElementCore
     this.rootCss = this.getRootCss();
     this.updateNavigationCss();
     this.updateCompletedPageCss();
-    this.updateBackgroundImageCss();
     this.updateWrapperFormCss();
   }
   /**
@@ -2098,13 +2097,6 @@ export class SurveyModel extends SurveyElementCore
       backgroundAttachment: !this.fitToContainer ? this.backgroundImageAttachment : undefined
     };
   }
-  @property() backgroundImageCss: string;
-  public updateBackgroundImageCss(): void {
-    this.backgroundImageCss = new CssClassBuilder()
-      .append(this.css.rootBackgroundImage)
-      .append(this.css.rootBackgroundImageFixed, this.backgroundImageFixed)
-      .toString();
-  }
   @property() wrapperFormCss: string;
   public updateWrapperFormCss(): void {
     this.wrapperFormCss = new CssClassBuilder()