Hoist inline style objects to module-level constants

Avoid recreating style objects on every render in MobileBottomNav,
FloatingComposeButton, and MobileDrawer by extracting them to
module-level constants.

src/components/FloatingComposeButton.tsx

@@ -11,6 +11,11 @@ import { PlanetButton } from '@/components/icons/PlanetButton';
 import { ReplyComposeModal } from '@/components/ReplyComposeModal';
 import { useCurrentUser } from '@/hooks/useCurrentUser';
 
+/** Drop shadow style for the planet FAB — hoisted to avoid re-creating on every render. */
+const fabShadowStyle: React.CSSProperties = {
+  filter: 'drop-shadow(0 4px 12px hsl(var(--primary) / 0.4)) drop-shadow(0 2px 4px hsl(var(--primary) / 0.2))',
+};
+
 interface FloatingComposeButtonProps {
   /** The Nostr event kind this FAB creates. kind=1 opens compose; others show "Coming soon". */
   kind?: number;
@@ -49,9 +54,7 @@ export function FloatingComposeButton({ kind = 1, href, onFabClick, icon }: Floa
       <button
         onClick={handleClick}
         className="relative size-16 transition-transform hover:scale-105 active:scale-95"
-        style={{
-          filter: 'drop-shadow(0 4px 12px hsl(var(--primary) / 0.4)) drop-shadow(0 2px 4px hsl(var(--primary) / 0.2))',
-        }}
+        style={fabShadowStyle}
       >
         <PlanetButton />
         {/* Plus icon centered on the planet body */}

src/components/MobileBottomNav.tsx

@@ -13,6 +13,11 @@ import { useLayoutSnapshot } from '@/contexts/LayoutContext';
 import { ArcBackground, ARC_OVERHANG_PX } from '@/components/ArcBackground';
 import { MobileSearchSheet } from '@/components/MobileSearchSheet';
 
+/** Transform style applied when the bottom nav is hidden (scrolled away). */
+const hiddenStyle: React.CSSProperties = {
+  transform: `translateY(calc(100% + ${ARC_OVERHANG_PX}px))`,
+};
+
 export function MobileBottomNav() {
   const location = useLocation();
   const { user, metadata } = useCurrentUser();
@@ -43,7 +48,7 @@ export function MobileBottomNav() {
           'fixed bottom-0 left-0 right-0 z-40 sidebar:hidden safe-area-bottom will-change-transform',
           'transition-transform duration-300 ease-in-out',
         )}
-        style={isHidden ? { transform: `translateY(calc(100% + ${ARC_OVERHANG_PX}px))` } : undefined}
+        style={isHidden ? hiddenStyle : undefined}
       >
         <ArcBackground variant="up" />
 

src/components/MobileDrawer.tsx

@@ -32,6 +32,12 @@ import { resolveTheme, resolveThemeConfig } from '@/themes';
 /** Total width of the drawer background layer: 300px drawer + 36px arc overhang. */
 const DRAWER_BG_WIDTH = 336;
 
+/** Shared clip-path style for the drawer arc background layers. */
+const drawerClipStyle: React.CSSProperties = {
+  width: DRAWER_BG_WIDTH,
+  clipPath: 'url(#drawer-arc-clip)',
+};
+
 interface MobileDrawerProps {
   open: boolean;
   onOpenChange: (open: boolean) => void;
@@ -119,19 +125,12 @@ export function MobileDrawer({ open, onOpenChange }: MobileDrawerProps) {
               seamlessly through both regions. */}
           <div
             className="absolute top-0 left-0 bottom-0 pointer-events-none bg-background"
-            style={{
-              ...bgStyle,
-              width: DRAWER_BG_WIDTH,
-              clipPath: 'url(#drawer-arc-clip)',
-            }}
+            style={{ ...bgStyle, ...drawerClipStyle }}
           />
           {hasBgImage && (
             <div
               className="absolute top-0 left-0 bottom-0 bg-background/70 pointer-events-none"
-              style={{
-                width: DRAWER_BG_WIDTH,
-                clipPath: 'url(#drawer-arc-clip)',
-              }}
+              style={drawerClipStyle}
             />
           )}
           <SheetTitle className="sr-only">Navigation menu</SheetTitle>