diff --git a/packages/vkui/src/components/Box/Box.tsx b/packages/vkui/src/components/Box/Box.tsx
index 75effe340d9..3b3c0d3ed5a 100644
--- a/packages/vkui/src/components/Box/Box.tsx
+++ b/packages/vkui/src/components/Box/Box.tsx
@@ -1,3 +1,6 @@
+'use client';
+
+import * as React from 'react';
 import { classNames } from '@vkontakte/vkjs';
 import { resolveLayoutProps } from '../../lib/layouts';
 import type { LayoutProps } from '../../lib/layouts/types';
@@ -12,7 +15,45 @@ const displayClassNames = {
   'contents': styles.displayContents,
 };
 
-export interface BoxProps extends RootComponentProps<HTMLElement>, LayoutProps {
+type BoxComponent = RootComponentProps<HTMLElement>['Component'] | React.ElementType[];
+
+function composeComponents(
+  component: BoxComponent | undefined,
+): RootComponentProps<HTMLElement>['Component'] {
+  if (!Array.isArray(component)) {
+    return component;
+  }
+
+  if (component.length === 0) {
+    return undefined;
+  }
+
+  return component.reduceRight<React.ElementType>(
+    (InnerComponent, WrapperComponent) =>
+      // eslint-disable-next-line react/display-name -- динамическая композиция обёрток
+      React.forwardRef<HTMLElement, RootComponentProps<HTMLElement>>((props, ref) => (
+        <WrapperComponent {...props} ref={ref} Component={InnerComponent} />
+      )),
+    'div',
+  );
+}
+
+export interface BoxProps extends Omit<RootComponentProps<HTMLElement>, 'Component'>, LayoutProps {
+  /**
+   * Компонент для рендера или массив компонентов для композиции.
+   *
+   * Можно передать один компонент или массив компонентов. При передаче массива
+   * компоненты будут вложены друг в друга справа налево, начиная с `div`.
+   *
+   * @example
+   * // Один компонент
+   * <Box Component="section" />
+   *
+   * @example
+   * // Массив компонентов — рендер: Wrapper → Link → div
+   * <Box Component={[Wrapper, Link]} />
+   */
+  Component?: BoxComponent | undefined;
   /**
    * Возможность задать css-свойство `display`.
    */
@@ -24,12 +65,21 @@ export interface BoxProps extends RootComponentProps<HTMLElement>, LayoutProps {
  *
  * @since 7.9.0
  */
-export const Box = ({ className, style, display, ...restProps }: BoxProps) => {
+export const Box = ({
+  className,
+  style,
+  display,
+  Component: ComponentProp,
+  ...restProps
+}: BoxProps) => {
   const resolvedProps = resolveLayoutProps(restProps);
 
+  const Component = React.useMemo(() => composeComponents(ComponentProp), [ComponentProp]);
+
   return (
     <RootComponent
       {...resolvedProps}
+      Component={Component}
       baseClassName={resolvedProps.className}
       baseStyle={resolvedProps.style}
       className={classNames(className, display && displayClassNames[display])}
diff --git a/packages/vkui/src/components/FixedLayout/SplitColWidthWrapper.tsx b/packages/vkui/src/components/FixedLayout/SplitColWidthWrapper.tsx
new file mode 100644
index 00000000000..908c9cc5890
--- /dev/null
+++ b/packages/vkui/src/components/FixedLayout/SplitColWidthWrapper.tsx
@@ -0,0 +1,47 @@
+'use client';
+
+import * as React from 'react';
+import { usePlatform } from '../../hooks/usePlatform';
+import { useResizeObserver } from '../../hooks/useResizeObserver';
+import { defineComponentDisplayNames } from '../../lib/react/defineComponentDisplayNames';
+import type { HasComponent } from '../../types';
+import { SplitColContext } from '../SplitCol/SplitColContext';
+
+type SplitColWidthWrapperProps = React.HTMLAttributes<HTMLElement> & HasComponent;
+
+export const SplitColWidthWrapper: React.ForwardRefExoticComponent<
+  React.PropsWithoutRef<SplitColWidthWrapperProps> & React.RefAttributes<HTMLElement>
+  // eslint-disable-next-line react/display-name -- используется defineComponentDisplayNames
+> = React.forwardRef<HTMLElement, SplitColWidthWrapperProps>(
+  ({ Component = 'div', style, ...restProps }, forwardedRef) => {
+    const platform = usePlatform();
+    const { colRef } = React.useContext(SplitColContext);
+    const [width, setWidth] = React.useState<string | undefined>(undefined);
+
+    const doResize = React.useCallback(() => {
+      if (!colRef?.current) {
+        setWidth(undefined);
+        return;
+      }
+
+      const computedStyle = getComputedStyle(colRef.current);
+
+      setWidth(
+        `${
+          colRef.current.clientWidth -
+          parseFloat(computedStyle.paddingLeft || '0') -
+          parseFloat(computedStyle.paddingRight || '0')
+        }px`,
+      );
+    }, [colRef]);
+
+    React.useEffect(doResize, [doResize, platform]);
+    useResizeObserver(colRef, doResize);
+
+    return <Component {...restProps} ref={forwardedRef} style={{ width, ...style }} />;
+  },
+);
+
+if (process.env.NODE_ENV !== 'production') {
+  defineComponentDisplayNames(SplitColWidthWrapper, 'SplitColWidthWrapper');
+}
diff --git a/packages/vkui/src/components/OnboardingTooltip/OnboardingTooltipFixedContainer.tsx b/packages/vkui/src/components/OnboardingTooltip/OnboardingTooltipFixedContainer.tsx
new file mode 100644
index 00000000000..7a160cd2873
--- /dev/null
+++ b/packages/vkui/src/components/OnboardingTooltip/OnboardingTooltipFixedContainer.tsx
@@ -0,0 +1,19 @@
+'use client';
+
+import * as React from 'react';
+import { defineComponentDisplayNames } from '../../lib/react/defineComponentDisplayNames';
+import type { HasComponent } from '../../types';
+import { OnboardingTooltipContainer } from './OnboardingTooltipContainer';
+
+type OnboardingTooltipFixedContainerProps = React.HTMLAttributes<HTMLDivElement> & HasComponent;
+
+export const OnboardingTooltipFixedContainer: React.ForwardRefExoticComponent<
+  React.PropsWithoutRef<OnboardingTooltipFixedContainerProps> & React.RefAttributes<HTMLDivElement>
+  // eslint-disable-next-line react/display-name -- используется defineComponentDisplayNames
+> = React.forwardRef<HTMLDivElement, OnboardingTooltipFixedContainerProps>((props, ref) => (
+  <OnboardingTooltipContainer {...props} fixed ref={ref} />
+));
+
+if (process.env.NODE_ENV !== 'production') {
+  defineComponentDisplayNames(OnboardingTooltipFixedContainer, 'OnboardingTooltipFixedContainer');
+}
diff --git a/packages/vkui/src/components/PanelHeader/PanelHeader.tsx b/packages/vkui/src/components/PanelHeader/PanelHeader.tsx
index cb1f3b9fe10..adb0ad60ee4 100644
--- a/packages/vkui/src/components/PanelHeader/PanelHeader.tsx
+++ b/packages/vkui/src/components/PanelHeader/PanelHeader.tsx
@@ -16,8 +16,9 @@ import type {
   HasRef,
   HTMLAttributesWithRootRef,
 } from '../../types';
+import { Box } from '../Box/Box';
 import { useConfigProvider } from '../ConfigProvider/ConfigProviderContext';
-import { FixedLayout } from '../FixedLayout/FixedLayout';
+import { SplitColWidthWrapper } from '../FixedLayout/SplitColWidthWrapper';
 import { OnboardingTooltipContainer } from '../OnboardingTooltip/OnboardingTooltipContainer';
 import { RootComponent } from '../RootComponent/RootComponent';
 import { Separator } from '../Separator/Separator';
@@ -201,15 +202,18 @@ export const PanelHeader = ({
       getRootRef={isFixed ? getRootRef : getRef}
     >
       {isFixed ? (
-        <FixedLayout
+        <Box
+          Component={SplitColWidthWrapper}
           className={classNames(styles.fixed, 'vkuiInternalPanelHeader__fixed')}
-          vertical="top"
+          position="fixed"
+          insetBlockStart={0}
+          inlineSize="100%"
           getRootRef={getRef}
         >
           <PanelHeaderIn before={before} after={after} typographyProps={typographyProps}>
             {children}
           </PanelHeaderIn>
-        </FixedLayout>
+        </Box>
       ) : (
         <PanelHeaderIn before={before} after={after} typographyProps={typographyProps}>
           {children}
diff --git a/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.module.css b/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.module.css
index ba8ddf16ee1..3da3a8f9e40 100644
--- a/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.module.css
+++ b/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.module.css
@@ -2,8 +2,6 @@
   --vkui_internal--PanelHeaderContext__fade_display: none;
 
   z-index: var(--vkui_internal--z_index_panel_header_context);
-  inline-size: 100%;
-  block-size: auto;
 }
 
 .viewWidthSmallTabletMinus {
@@ -171,3 +169,13 @@
     opacity: 0;
   }
 }
+
+/* stylelint-disable selector-max-universal, selector-pseudo-class-disallowed-list */
+:global(.vkuiInternalPanelHeader) ~ .host,
+:global(.vkuiInternalPanelHeader) ~ * .host {
+  inset-block-start: calc(
+    var(--vkui_internal--panel_header_height) +
+    var(--vkui_internal--safe_area_inset_top)
+  );
+}
+/* stylelint-enable selector-max-universal, selector-pseudo-class-disallowed-list */
diff --git a/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.tsx b/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.tsx
index d6b2eab4dd2..c986760c0fb 100644
--- a/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.tsx
+++ b/packages/vkui/src/components/PanelHeaderContext/PanelHeaderContext.tsx
@@ -9,7 +9,9 @@ import { type SizeTypeValues, ViewWidth, type ViewWidthType } from '../../lib/ad
 import { useCSSKeyframesAnimationController } from '../../lib/animation';
 import type { HTMLAttributesWithRootRef } from '../../types';
 import { useScrollLock } from '../AppRoot/ScrollContext';
-import { FixedLayout } from '../FixedLayout/FixedLayout';
+import { Box } from '../Box/Box';
+import { SplitColWidthWrapper } from '../FixedLayout/SplitColWidthWrapper';
+import { OnboardingTooltipFixedContainer } from '../OnboardingTooltip/OnboardingTooltipFixedContainer';
 import styles from './PanelHeaderContext.module.css';
 
 function getViewWidthClassName(
@@ -43,6 +45,8 @@ export interface PanelHeaderContextProps extends HTMLAttributesWithRootRef<HTMLD
   onClose: VoidFunction;
 }
 
+const ComponentDecorators = [SplitColWidthWrapper, OnboardingTooltipFixedContainer];
+
 /**
  * @see https://vkui.io/components/panel-header-context
  */
@@ -82,8 +86,8 @@ export const PanelHeaderContext = ({
   }
 
   return (
-    <FixedLayout
-      {...restProps}
+    <Box
+      Component={ComponentDecorators}
       className={classNames(
         styles.host,
         platform === 'ios' && styles.ios,
@@ -91,7 +95,10 @@ export const PanelHeaderContext = ({
         getViewWidthClassName(viewWidth, legacySizeX),
         className,
       )}
-      vertical="top"
+      position="fixed"
+      inlineSize="100%"
+      insetBlockStart={0}
+      {...restProps}
     >
       <div
         onClick={(event) => {
@@ -108,6 +115,6 @@ export const PanelHeaderContext = ({
       >
         <div className={styles.content}>{children}</div>
       </div>
-    </FixedLayout>
+    </Box>
   );
 };