diff --git a/.changeset/real-years-watch.md b/.changeset/real-years-watch.md
new file mode 100644
index 00000000..39e3528b
--- /dev/null
+++ b/.changeset/real-years-watch.md
@@ -0,0 +1,7 @@
+---
+'@flatfile/react': minor
+---
+
+Adds new useFlatfile({ onClose }) close event handler on useFlatfile hook
+Restores missing stylesheet for legacy deprecated useSpace and usePortal flows
+Flatfile modal now fills entire screen by default, style overrides may need to be adjusted
diff --git a/apps/react/app/App.tsx b/apps/react/app/App.tsx
index 821417d0..f1ec1bfb 100644
--- a/apps/react/app/App.tsx
+++ b/apps/react/app/App.tsx
@@ -16,7 +16,10 @@ import { useEffect, useState } from 'react'
 import styles from './page.module.css'
 
 const App = () => {
-  const { open, openPortal, closePortal } = useFlatfile()
+  function logClosed() {
+    console.log('Flatfile Portal closed')
+  }
+  const { open, openPortal, closePortal } = useFlatfile({ onClose: logClosed })
   const [label, setLabel] = useState('Rock')
   const toggleOpen = () => {
     open ? closePortal({ reset: false }) : openPortal()
diff --git a/apps/react/app/OldApp.tsx b/apps/react/app/OldApp.tsx
index 29e34d9e..ca642af0 100644
--- a/apps/react/app/OldApp.tsx
+++ b/apps/react/app/OldApp.tsx
@@ -1,7 +1,7 @@
 'use client'
 import { sheet } from '@/utils/sheet'
 import { InitSpace, initializeFlatfile, usePortal } from '@flatfile/react'
-import React, { Dispatch, SetStateAction, useState } from 'react'
+import { Dispatch, SetStateAction, useState } from 'react'
 import { config } from './config'
 import { listener } from './listener'
 import styles from './page.module.css'
@@ -85,33 +85,43 @@ function App() {
 
   return (
     <div className={styles.main}>
-      <div className={styles.description}>
-        <button
-          onClick={async () => {
-            setShowSpace(!showSpace)
-            await OpenEmbed()
-          }}
-        >
-          {showSpace === true ? 'Close' : 'Open'} space
-        </button>
-      </div>
-      <div className={styles.description}>
-        <button
-          onClick={() => {
-            setShowSimplified(!showSimplified)
-          }}
-        >
-          {showSimplified === true ? 'Close' : 'Open'} Simplified
-        </button>
-      </div>
-      <div className={styles.description}>
-        <button
-          onClick={() => {
-            setActivatePreloaded(!showSimplified)
-          }}
-        >
-          {showSimplified === true ? 'Close' : 'Open'} Pre-loaded
-        </button>
+      <div
+        className={styles.description}
+        style={{
+          display: 'flex',
+          flexDirection: 'row',
+          justifyContent: 'flex-start',
+          gap: '10px',
+        }}
+      >
+        <div>
+          <button
+            onClick={async () => {
+              setShowSpace(!showSpace)
+              await OpenEmbed()
+            }}
+          >
+            {showSpace === true ? 'Close' : 'Open'} space
+          </button>
+        </div>
+        <div>
+          <button
+            onClick={() => {
+              setShowSimplified(!showSimplified)
+            }}
+          >
+            {showSimplified === true ? 'Close' : 'Open'} Simplified
+          </button>
+        </div>
+        <div>
+          <button
+            onClick={() => {
+              setActivatePreloaded(!showSimplified)
+            }}
+          >
+            {showSimplified === true ? 'Close' : 'Open'} Pre-loaded
+          </button>
+        </div>
       </div>
       {showSpace && (
         <div className={styles.spaceWrapper}>
diff --git a/apps/react/app/globals.css b/apps/react/app/globals.css
index 0a2ce99d..2f62d7c9 100644
--- a/apps/react/app/globals.css
+++ b/apps/react/app/globals.css
@@ -110,7 +110,13 @@ a {
   }
 }
 
+.flatfile_iframe-wrapper,
+.flatfile_initIframe-wrapper {
+  top: 60px !important;
+  height: calc(100dvh - 60px) !important;
+}
 
-.flatfile_iframe-wrapper {
-  top: 100px !important;
-}
\ No newline at end of file
+.flatfile_iFrameContainer,
+.flatfile_initIFrameContainer {
+  height: auto !important;
+}
diff --git a/apps/react/app/page.tsx b/apps/react/app/page.tsx
index f80d3d5e..5d7ea21c 100644
--- a/apps/react/app/page.tsx
+++ b/apps/react/app/page.tsx
@@ -6,7 +6,9 @@ import { FlatfileProvider } from '@flatfile/react'
 
 export default function Home() {
   const PUBLISHABLE_KEY = process.env.NEXT_PUBLIC_FLATFILE_PUBLISHABLE_KEY
-  if (!PUBLISHABLE_KEY) return <>No Publishable Key Available</>
+  if (!PUBLISHABLE_KEY) {
+    return <>No Publishable Key Available</>
+  }
   return (
     <FlatfileProvider
       publishableKey={PUBLISHABLE_KEY}
diff --git a/packages/react/src/components/FlatfileContext.tsx b/packages/react/src/components/FlatfileContext.tsx
index ff7aaee3..f9aa4afd 100644
--- a/packages/react/src/components/FlatfileContext.tsx
+++ b/packages/react/src/components/FlatfileContext.tsx
@@ -28,6 +28,8 @@ export interface FlatfileContextType {
   environmentId?: string
   apiUrl: string
   open: boolean
+  onClose?: () => void
+  setOnClose: (onClose: () => (undefined | (() => void))) => void,
   setOpen: (open: boolean) => void
   space?: CreateNewSpace | ReUseSpace
   sessionSpace?: any
@@ -59,6 +61,8 @@ export const FlatfileContext = createContext<FlatfileContextType>({
   environmentId: undefined,
   apiUrl: '',
   open: true,
+  onClose: undefined,
+  setOnClose: () => {},
   setOpen: () => {},
   space: undefined,
   sessionSpace: undefined,
diff --git a/packages/react/src/components/FlatfileProvider.tsx b/packages/react/src/components/FlatfileProvider.tsx
index 7aa68248..52b71b2d 100644
--- a/packages/react/src/components/FlatfileProvider.tsx
+++ b/packages/react/src/components/FlatfileProvider.tsx
@@ -17,9 +17,15 @@ import { convertDatesToISO } from '../utils/convertDatesToISO'
 import { createSpaceInternal } from '../utils/createSpaceInternal'
 import { getSpace } from '../utils/getSpace'
 import { EmbeddedIFrameWrapper } from './EmbeddedIFrameWrapper'
-import FlatfileContext, { DEFAULT_CREATE_SPACE } from './FlatfileContext'
+import FlatfileContext, {
+  DEFAULT_CREATE_SPACE,
+  FlatfileContextType,
+} from './FlatfileContext'
 
-import { attachStyleSheet } from '../utils/attachStyleSheet'
+import {
+  attachStyleSheet,
+  useAttachStyleSheet,
+} from '../utils/attachStyleSheet'
 
 const configDefaults: IFrameTypes = {
   preload: true,
@@ -41,6 +47,7 @@ export const FlatfileProvider: React.FC<ExclusiveFlatfileProviderProps> = ({
   apiUrl = 'https://platform.flatfile.com/api',
   config,
 }) => {
+  useAttachStyleSheet(config?.styleSheetOptions)
   const [internalAccessToken, setInternalAccessToken] = useState<
     string | undefined | null
   >(accessToken)
@@ -56,6 +63,8 @@ export const FlatfileProvider: React.FC<ExclusiveFlatfileProviderProps> = ({
     space: Flatfile.SpaceConfig & { id?: string }
   }>(DEFAULT_CREATE_SPACE)
 
+  const [onClose, setOnClose] = useState<undefined | (() => void)>()
+
   const iframe = useRef<HTMLIFrameElement>(null)
 
   const FLATFILE_PROVIDER_CONFIG = { ...config, ...configDefaults }
@@ -217,15 +226,9 @@ export const FlatfileProvider: React.FC<ExclusiveFlatfileProviderProps> = ({
       }
       // Works but only after the iframe is visible
     }
-  }
-  const styleSheetRef = useRef(false)
 
-  useEffect(() => {
-    if (!styleSheetRef.current) {
-      attachStyleSheet(config?.styleSheetOptions)
-      styleSheetRef.current = true
-    }
-  }, [config?.styleSheetOptions, styleSheetRef])
+    onClose?.()
+  }
 
   // Listen to the postMessage event from the created iFrame
   useEffect(() => {
@@ -280,12 +283,14 @@ export const FlatfileProvider: React.FC<ExclusiveFlatfileProviderProps> = ({
   }, [ready, open])
 
   const providerValue = useMemo(
-    () => ({
+    (): FlatfileContextType => ({
       ...(publishableKey ? { publishableKey } : {}),
       ...(internalAccessToken ? { accessToken: internalAccessToken } : {}),
       apiUrl,
       environmentId,
       open,
+      onClose,
+      setOnClose,
       setOpen,
       sessionSpace,
       setSessionSpace,
@@ -319,6 +324,8 @@ export const FlatfileProvider: React.FC<ExclusiveFlatfileProviderProps> = ({
       ready,
       iframe,
       FLATFILE_PROVIDER_CONFIG,
+      onClose,
+      setOnClose,
     ]
   )
 
diff --git a/packages/react/src/components/_tests_/FlatfileProvider.spec.tsx b/packages/react/src/components/_tests_/FlatfileProvider.spec.tsx
index c68e3a98..fd615cb1 100644
--- a/packages/react/src/components/_tests_/FlatfileProvider.spec.tsx
+++ b/packages/react/src/components/_tests_/FlatfileProvider.spec.tsx
@@ -13,6 +13,8 @@ export const FlatfileProviderValue: FlatfileContextType = {
   apiUrl: '',
   open: false,
   setOpen: jest.fn(),
+  onClose: undefined,
+  setOnClose: jest.fn(),
   setSessionSpace: jest.fn(),
   listener: new FlatfileListener(),
   setListener: jest.fn(),
diff --git a/packages/react/src/components/embeddedStyles.tsx b/packages/react/src/components/embeddedStyles.tsx
index b83dfb66..ab472415 100644
--- a/packages/react/src/components/embeddedStyles.tsx
+++ b/packages/react/src/components/embeddedStyles.tsx
@@ -17,16 +17,19 @@ export const getContainerStyles = (isModal: boolean): React.CSSProperties => {
   return isModal
     ? {
         backgroundColor: 'rgba(0, 0, 0, 0.1)',
+        boxSizing: 'border-box',
         display: 'flex',
-        height: 'calc(100vh - 40px)',
-        width: 'calc(100% - 100px)',
+        height: '100dvh',
+        width: '100dvw',
+        left: '0',
+        top: '0',
         padding: '50px',
         position: 'fixed',
         zIndex: '1000',
       }
     : {
-        width: '100%',
         height: '100%',
+        width: '100%',
         display: 'flex',
         justifyContent: 'center',
         alignItems: 'center',
diff --git a/packages/react/src/components/style.scss b/packages/react/src/components/style.scss
index 0d49273a..580949c1 100644
--- a/packages/react/src/components/style.scss
+++ b/packages/react/src/components/style.scss
@@ -39,6 +39,7 @@
 }
 
 .flatfile_iframe-wrapper {
+  box-sizing: border-box;
   color: var(--ff-text-color);
   font-family: var(--ff-text-font);
   font-size: var(--size-base);
@@ -46,6 +47,12 @@
   margin: 0;
   transition: opacity 0.25s ease-in-out;
 }
+.flatfile_iframe-wrapper.flatfile_displayAsModal {
+  height: 100%;
+  height: 100vh;
+  width: 100%;
+  width: 100vw;
+}
 .flatfile-close-button svg {
   fill: lightgray;
   width: 10px;
@@ -167,11 +174,11 @@
   box-sizing: border-box;
   display: block;
   height: 100%;
-  left: 0px;
+  left: 0;
   overflow-y: auto;
-  position: fixed;
-  right: 0px;
+  position: absolute;
   tab-size: 4;
+  top: 0;
   width: 100%;
   z-index: 1200;
 }
diff --git a/packages/react/src/hooks/legacy/usePortal.tsx b/packages/react/src/hooks/legacy/usePortal.tsx
index 777628da..ef15f945 100644
--- a/packages/react/src/hooks/legacy/usePortal.tsx
+++ b/packages/react/src/hooks/legacy/usePortal.tsx
@@ -1,23 +1,24 @@
-import React, { JSX, useEffect, useState } from 'react'
-import DefaultError from '../../components/legacy/Error'
-import Space from '../../components/legacy/LegacySpace'
-import Spinner from '../../components/Spinner'
+// Bug where the default export function is not being used properly in some build tooling
+import { FlatfileClient } from '@flatfile/api'
 import {
-  State,
-  JobHandler,
-  SheetHandler,
   createWorkbookFromSheet,
   DefaultSubmitSettings,
+  JobHandler,
+  SheetHandler,
+  State,
 } from '@flatfile/embedded-utils'
-import { initializeSpace } from '../../utils/initializeSpace'
-import { getSpace } from '../../utils/getSpace'
 import { FlatfileRecord } from '@flatfile/hooks'
 import { FlatfileEvent, FlatfileListener } from '@flatfile/listener'
 import { recordHook } from '@flatfile/plugin-record-hook'
+import React, { JSX, useEffect, useState } from 'react'
+import DefaultError from '../../components/legacy/Error'
+import Space from '../../components/legacy/LegacySpace'
+import Spinner from '../../components/Spinner'
 import { IReactSimpleOnboarding } from '../../types/IReactSimpleOnboarding'
+import { useAttachStyleSheet } from '../../utils/attachStyleSheet'
+import { getSpace } from '../../utils/getSpace'
+import { initializeSpace } from '../../utils/initializeSpace'
 
-// Bug where the default export function is not being used properly in some build tooling
-import { FlatfileClient } from '@flatfile/api'
 const api = new FlatfileClient()
 /**
  * @deprecated - use FlatfileProvider and Space components instead
@@ -26,6 +27,7 @@ const api = new FlatfileClient()
 export const usePortal = (
   props: IReactSimpleOnboarding
 ): JSX.Element | null => {
+  useAttachStyleSheet()
   const { errorTitle, loading: LoadingElement, apiUrl } = props
   const [initError, setInitError] = useState<string>()
   const [state, setState] = useState<State>({
diff --git a/packages/react/src/hooks/legacy/useSpace.tsx b/packages/react/src/hooks/legacy/useSpace.tsx
index 3fa351c3..bab7e1a5 100644
--- a/packages/react/src/hooks/legacy/useSpace.tsx
+++ b/packages/react/src/hooks/legacy/useSpace.tsx
@@ -1,17 +1,19 @@
+import { State } from '@flatfile/embedded-utils'
 import React, { JSX, useEffect, useState } from 'react'
 import DefaultError from '../../components/legacy/Error'
 import Space from '../../components/legacy/LegacySpace'
 import Spinner from '../../components/Spinner'
-import { State } from '@flatfile/embedded-utils'
-import { initializeSpace } from '../../utils/initializeSpace'
-import { getSpace } from '../../utils/getSpace'
 import { IReactSpaceProps } from '../../types'
+import { useAttachStyleSheet } from '../../utils/attachStyleSheet'
+import { getSpace } from '../../utils/getSpace'
+import { initializeSpace } from '../../utils/initializeSpace'
 
 /**
  * @deprecated - use FlatfileProvider and Space components instead
  * This hook is used to initialize a space and return the Space component
  */
 export const useSpace = (props: IReactSpaceProps): JSX.Element | null => {
+  useAttachStyleSheet()
   const {
     error: ErrorElement,
     errorTitle,
diff --git a/packages/react/src/hooks/legacy/useSpaceTrigger.tsx b/packages/react/src/hooks/legacy/useSpaceTrigger.tsx
index 712f17c8..36a6b5cb 100644
--- a/packages/react/src/hooks/legacy/useSpaceTrigger.tsx
+++ b/packages/react/src/hooks/legacy/useSpaceTrigger.tsx
@@ -1,11 +1,12 @@
+import { State } from '@flatfile/embedded-utils'
 import React, { JSX, useState } from 'react'
 import DefaultError from '../../components/legacy/Error'
 import Space from '../../components/legacy/LegacySpace'
 import Spinner from '../../components/Spinner'
-import { State } from '@flatfile/embedded-utils'
-import { initializeSpace } from '../../utils/initializeSpace'
-import { getSpace } from '../../utils/getSpace'
 import { IReactSpaceProps } from '../../types'
+import { useAttachStyleSheet } from '../../utils/attachStyleSheet'
+import { getSpace } from '../../utils/getSpace'
+import { initializeSpace } from '../../utils/initializeSpace'
 
 type IUseSpace = { OpenEmbed: () => Promise<void>; Space: () => JSX.Element }
 
@@ -15,6 +16,7 @@ type IUseSpace = { OpenEmbed: () => Promise<void>; Space: () => JSX.Element }
  */
 
 export const initializeFlatfile = (props: IReactSpaceProps): IUseSpace => {
+  useAttachStyleSheet()
   const { error: ErrorElement, errorTitle, loading: LoadingElement } = props
   const [initError, setInitError] = useState<Error | string>()
   const [loading, setLoading] = useState<boolean>(false)
diff --git a/packages/react/src/hooks/useFlatfile.ts b/packages/react/src/hooks/useFlatfile.ts
index f54d6558..1f7fbf8b 100644
--- a/packages/react/src/hooks/useFlatfile.ts
+++ b/packages/react/src/hooks/useFlatfile.ts
@@ -1,31 +1,49 @@
-import { useContext } from 'react'
+import { useCallback, useContext, useEffect } from 'react'
 import FlatfileContext from '../components/FlatfileContext'
 import { ClosePortalOptions } from '../types'
 
-export const useFlatfile: () => {
+interface UseFlatfileOptions {
+  onClose?: () => void
+}
+
+export const useFlatfile: (useFlatfileOptions?: UseFlatfileOptions) => {
   openPortal: () => void
   closePortal: (options?: ClosePortalOptions) => void
   open: boolean
   setListener: (listener: any) => void
   listener: any
-} = () => {
+} = (useFlatfileOptions: UseFlatfileOptions = {}) => {
   const context = useContext(FlatfileContext)
 
   if (!context) {
     throw new Error('useFlatfile must be used within a FlatfileProvider')
   }
 
+  const onCloseCallback = useCallback(
+    useFlatfileOptions.onClose ?? (() => {}),
+    [typeof useFlatfileOptions.onClose]
+  )
+
+  useEffect(() => {
+    if (context.onClose !== onCloseCallback) {
+      context.setOnClose(() => onCloseCallback)
+    }
+  }, [context.onClose, context.setOnClose, onCloseCallback])
+
   const { open, setOpen, setListener, listener, apiUrl, resetSpace, ready } =
     context
 
-  const openPortal = () => {
+  const openPortal = useCallback(() => {
     ;(window as any).CROSSENV_FLATFILE_API_URL = apiUrl
     setOpen(true)
-  }
+  }, [setOpen, apiUrl])
 
-  const closePortal = (options?: ClosePortalOptions) => {
-    resetSpace(options)
-  }
+  const closePortal = useCallback(
+    (options?: ClosePortalOptions) => {
+      resetSpace(options)
+    },
+    [resetSpace]
+  )
 
   return {
     openPortal,
diff --git a/packages/react/src/utils/attachStyleSheet.ts b/packages/react/src/utils/attachStyleSheet.ts
index bf141429..28186d72 100644
--- a/packages/react/src/utils/attachStyleSheet.ts
+++ b/packages/react/src/utils/attachStyleSheet.ts
@@ -1,6 +1,7 @@
 import { styleInject } from '../utils/styleInject'
 
 import stylesheet from '../components/style.scss'
+import { MutableRefObject } from 'react'
 export type StyleSheetOptions = {
   insertAt?: 'top'
   nonce?: string
@@ -9,3 +10,12 @@ export type StyleSheetOptions = {
 export function attachStyleSheet(options?: StyleSheetOptions) {
   styleInject(stylesheet, options)
 }
+
+const styleSheetAttachedRef: MutableRefObject<boolean> = { current: false }
+
+export function useAttachStyleSheet(options?: StyleSheetOptions) {
+  if (!styleSheetAttachedRef.current) {
+    attachStyleSheet(options)
+    styleSheetAttachedRef.current = true
+  }
+}