chore(release): 4.63.5 [skip ci]

## [4.63.5](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.63.4...v4.63.5) (2025-10-21)

### Bug Fixes

* **flashcards:** store grab offset in local coordinates to prevent jump ([39d93a9](39d93a9e9f))

CHANGELOG.md

@@ -1,3 +1,142 @@
+## [4.63.5](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.63.4...v4.63.5) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** store grab offset in local coordinates to prevent jump ([39d93a9](https://github.com/antialias/soroban-abacus-flashcards/commit/39d93a9e9f48a7d1ce10763cad62a600851a41d5))
+
+## [4.63.4](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.63.3...v4.63.4) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** keep grab point under cursor with proper coordinate conversion ([1869216](https://github.com/antialias/soroban-abacus-flashcards/commit/1869216d2fda77303c0b79d4f613c6dcdaf5324b))
+
+## [4.63.3](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.63.2...v4.63.3) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** revert to simple delta positioning to prevent card jumping ([d018b69](https://github.com/antialias/soroban-abacus-flashcards/commit/d018b699c46aea90e9cdc3309e797ff2d7447ecf))
+
+## [4.63.2](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.63.1...v4.63.2) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** correct pivot point to rotate around card center ([50fc3fd](https://github.com/antialias/soroban-abacus-flashcards/commit/50fc3fdf7f2c9b7412f6d7d890f5e0d52cb86a9b))
+
+## [4.63.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.63.0...v4.63.1) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** increase rotation sensitivity 10x for visible grab point physics ([c0fa926](https://github.com/antialias/soroban-abacus-flashcards/commit/c0fa926d16d02c1bfe880b7f0056a760e8461b3b))
+
+## [4.63.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.62.1...v4.63.0) (2025-10-21)
+
+
+### Features
+
+* **flashcards:** add grab point physics for realistic rotation ([bf37eb1](https://github.com/antialias/soroban-abacus-flashcards/commit/bf37eb1928de8d07673234e2faa1fa6268c45686))
+
+## [4.62.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.62.0...v4.62.1) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** improve shadow speed logging with separate throttling ([0f51366](https://github.com/antialias/soroban-abacus-flashcards/commit/0f51366fd56540e691df4931b6350c03043484f1))
+
+## [4.62.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.61.3...v4.62.0) (2025-10-21)
+
+
+### Features
+
+* **flashcards:** add dynamic shadow based on drag speed ([92148a4](https://github.com/antialias/soroban-abacus-flashcards/commit/92148a4cf87e828ba2e5ec1740fb51d9667c1d73))
+
+## [4.61.3](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.61.2...v4.61.3) (2025-10-21)
+
+
+### Code Refactoring
+
+* **flashcards:** completely rewrite drag-drop with simple approach ([5f0ad14](https://github.com/antialias/soroban-abacus-flashcards/commit/5f0ad14133340d073e861f5721cb48e1abab03ff))
+
+## [4.61.2](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.61.1...v4.61.2) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** use explicit per-property configs to fix decay physics ([f32480a](https://github.com/antialias/soroban-abacus-flashcards/commit/f32480a0f9153285341e5a28078840abc0590873))
+
+## [4.61.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.61.0...v4.61.1) (2025-10-21)
+
+
+### Bug Fixes
+
+* **flashcards:** fix position snap-back by using api.set before decay ([30e16c8](https://github.com/antialias/soroban-abacus-flashcards/commit/30e16c8e5ac3bb25f2d54cf715dc6fb45adc4fcc))
+
+## [4.61.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.60.0...v4.61.0) (2025-10-21)
+
+
+### Features
+
+* **flashcards:** enable unbounded drag and position persistence ([ad1ad69](https://github.com/antialias/soroban-abacus-flashcards/commit/ad1ad690f014257b5a3c3f599e794205a11d286f))
+
+## [4.60.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.59.1...v4.60.0) (2025-10-21)
+
+
+### Features
+
+* **homepage:** significantly increase mobile hero abacus size ([424f41d](https://github.com/antialias/soroban-abacus-flashcards/commit/424f41d4bfc1ddea068f8c110b495ebd5c0bb455))
+
+## [4.59.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.59.0...v4.59.1) (2025-10-21)
+
+
+### Bug Fixes
+
+* **homepage:** adjust hero abacus scale for optimal sizing across devices ([86dee31](https://github.com/antialias/soroban-abacus-flashcards/commit/86dee31c9a51ca0712f1b4181a4899d25374d403))
+* **homepage:** reduce mobile abacus scale to prevent scroll hint overlap ([b8235be](https://github.com/antialias/soroban-abacus-flashcards/commit/b8235be612c3f1dbd0da2b6cd1a935001b7dac9b))
+
+## [4.59.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.58.2...v4.59.0) (2025-10-21)
+
+
+### Features
+
+* **homepage:** increase hero abacus size for better visibility ([7666b0a](https://github.com/antialias/soroban-abacus-flashcards/commit/7666b0aea949f2432a4d0f4648c1a366af3ea6d2))
+
+## [4.58.2](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.58.1...v4.58.2) (2025-10-21)
+
+
+### Code Refactoring
+
+* **navbar:** prevent subtitle wrap and remove abacus emoji ([a58f7b7](https://github.com/antialias/soroban-abacus-flashcards/commit/a58f7b78b0020c85da523c36fdf6d70ad069736a))
+
+## [4.58.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.58.0...v4.58.1) (2025-10-21)
+
+
+### Bug Fixes
+
+* **navbar:** apply glassmorphism to transparent mode, not scrolled mode ([8893675](https://github.com/antialias/soroban-abacus-flashcards/commit/8893675b36b1c1534c6fe7e57fa7e0cc55f198d6))
+
+## [4.58.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.57.10...v4.58.0) (2025-10-21)
+
+
+### Features
+
+* **navbar:** add glassmorphism effect to nav links when scrolled ([89b9072](https://github.com/antialias/soroban-abacus-flashcards/commit/89b90723b7a3fc9ed12da3ba8718fccb6ce0760f))
+
+## [4.57.10](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.57.9...v4.57.10) (2025-10-21)
+
+
+### Bug Fixes
+
+* **navbar:** remove border artifact and add 10px bottom fade ([d5f60ce](https://github.com/antialias/soroban-abacus-flashcards/commit/d5f60ce9d2fbc2a870b3bb96f5365a0e04e0afc4))
+
+
+### Styles
+
+* **navbar:** improve theming to match homepage dark aesthetic ([284fc90](https://github.com/antialias/soroban-abacus-flashcards/commit/284fc90a53f5f4868a3e41421760ebc813be12b5))
+
 ## [4.57.9](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.57.8...v4.57.9) (2025-10-21)
 
 

apps/web/src/components/AppNavBar.tsx

@@ -576,10 +576,11 @@ export function AppNavBar({ variant = 'full', navSlot }: AppNavBarProps) {
     <Tooltip.Provider delayDuration={200}>
       <header
         className={css({
-          bg: isTransparent ? 'transparent' : 'white',
-          shadow: isTransparent ? 'none' : 'sm',
+          bg: isTransparent ? 'transparent' : 'rgba(0, 0, 0, 0.5)',
+          backdropFilter: isTransparent ? 'none' : 'blur(12px)',
+          shadow: isTransparent ? 'none' : 'lg',
           borderBottom: isTransparent ? 'none' : '1px solid',
-          borderColor: isTransparent ? 'transparent' : 'gray.200',
+          borderColor: isTransparent ? 'transparent' : 'rgba(139, 92, 246, 0.2)',
           position: 'fixed',
           top: 0,
           left: 0,
@@ -599,7 +600,7 @@ export function AppNavBar({ variant = 'full', navSlot }: AppNavBarProps) {
                   flexDirection: 'column',
                   gap: '0',
                   textDecoration: 'none',
-                  _hover: { '& > .brand-name': { color: 'brand.900' } },
+                  _hover: { '& > .brand-name': { color: 'rgba(196, 181, 253, 1)' } },
                   opacity: 0,
                   animation: 'fadeIn 0.3s ease-out forwards',
                 })}
@@ -608,10 +609,10 @@ export function AppNavBar({ variant = 'full', navSlot }: AppNavBarProps) {
                   className={css({
                     fontSize: 'xl',
                     fontWeight: 'bold',
-                    color: 'brand.800',
+                    color: 'rgba(255, 255, 255, 0.95)',
                   })}
                 >
-                  🧮 Abaci One
+                  Abaci One
                 </span>
                 <Tooltip.Root>
                   <Tooltip.Trigger asChild>
@@ -619,10 +620,11 @@ export function AppNavBar({ variant = 'full', navSlot }: AppNavBarProps) {
                       className={css({
                         fontSize: 'xs',
                         fontWeight: 'medium',
-                        color: 'brand.600',
+                        color: 'rgba(196, 181, 253, 0.8)',
                         fontStyle: 'italic',
                         cursor: 'help',
-                        _hover: { color: 'brand.700' },
+                        whiteSpace: 'nowrap',
+                        _hover: { color: 'rgba(196, 181, 253, 1)' },
                       })}
                     >
                       {subtitle.text}
@@ -717,6 +719,9 @@ function NavLink({
   return (
     <Link
       href={href}
+      style={{
+        backdropFilter: isTransparent ? 'blur(8px)' : 'none',
+      }}
       className={css({
         px: { base: '4', md: '3' },
         py: { base: '3', md: '2' },
@@ -729,24 +734,33 @@ function NavLink({
             ? 'white'
             : 'rgba(255, 255, 255, 0.8)'
           : isActive
-            ? 'brand.700'
-            : 'gray.600',
+            ? 'rgba(196, 181, 253, 1)'
+            : 'rgba(209, 213, 219, 0.9)',
         bg: isTransparent
           ? isActive
-            ? 'rgba(255, 255, 255, 0.15)'
-            : 'transparent'
+            ? 'rgba(255, 255, 255, 0.2)'
+            : 'rgba(255, 255, 255, 0.08)'
           : isActive
-            ? 'brand.50'
+            ? 'rgba(139, 92, 246, 0.2)'
             : 'transparent',
+        border: isTransparent ? '1px solid' : 'none',
+        borderColor: isTransparent
+          ? isActive
+            ? 'rgba(255, 255, 255, 0.3)'
+            : 'rgba(255, 255, 255, 0.15)'
+          : 'transparent',
         rounded: 'lg',
         transition: 'all',
         textDecoration: 'none',
         display: 'flex',
         alignItems: 'center',
         justifyContent: 'center',
+        boxShadow: isTransparent ? '0 2px 8px rgba(0, 0, 0, 0.2)' : 'none',
         _hover: {
-          color: isTransparent ? 'white' : isActive ? 'brand.800' : 'gray.900',
-          bg: isTransparent ? 'rgba(255, 255, 255, 0.2)' : isActive ? 'brand.100' : 'gray.50',
+          color: isTransparent ? 'white' : 'rgba(196, 181, 253, 1)',
+          bg: isTransparent ? 'rgba(255, 255, 255, 0.25)' : 'rgba(139, 92, 246, 0.25)',
+          borderColor: isTransparent ? 'rgba(255, 255, 255, 0.4)' : 'transparent',
+          boxShadow: isTransparent ? '0 4px 12px rgba(0, 0, 0, 0.3)' : 'none',
         },
       })}
     >

apps/web/src/components/HeroAbacus.tsx

@@ -131,7 +131,7 @@ export function HeroAbacus() {
       >
         <div
           className={css({
-            transform: { base: 'scale(2)', md: 'scale(3)', lg: 'scale(4)' },
+            transform: { base: 'scale(3.5)', md: 'scale(3.5)', lg: 'scale(4.25)' },
             transformOrigin: 'center center',
             transition: 'all 0.5s cubic-bezier(0.4, 0, 0.2, 1)',
           })}

apps/web/src/components/InteractiveFlashcards.tsx

@@ -1,9 +1,7 @@
 'use client'
 
 import { AbacusReact } from '@soroban/abacus-react'
-import { useDrag } from '@use-gesture/react'
 import { useEffect, useRef, useState } from 'react'
-import { animated, config, to, useSpring } from '@react-spring/web'
 import { css } from '../../styled-system/css'
 
 interface Flashcard {
@@ -16,12 +14,11 @@ interface Flashcard {
 }
 
 /**
- * InteractiveFlashcards - A fun, physics-based flashcard display
- * Users can drag and throw flashcards around with realistic momentum
+ * InteractiveFlashcards - A fun flashcard display where you can drag cards around
+ * Cards stay where you drop them - simple and intuitive
  */
 export function InteractiveFlashcards() {
   const containerRef = useRef<HTMLDivElement>(null)
-  // Generate 8-15 random flashcards (client-side only to avoid hydration errors)
   const [cards, setCards] = useState<Flashcard[]>([])
 
   useEffect(() => {
@@ -77,14 +74,14 @@ export function InteractiveFlashcards() {
         maxW: '1200px',
         mx: 'auto',
         height: { base: '400px', md: '500px' },
-        overflow: 'hidden',
+        overflow: 'visible',
         bg: 'rgba(0, 0, 0, 0.3)',
         rounded: 'xl',
         border: '1px solid rgba(255, 255, 255, 0.1)',
       })}
     >
       {cards.map((card) => (
-        <DraggableCard key={card.id} card={card} />
+        <DraggableCard key={card.id} card={card} containerRef={containerRef} />
       ))}
     </div>
   )
@@ -92,193 +89,245 @@ export function InteractiveFlashcards() {
 
 interface DraggableCardProps {
   card: Flashcard
+  containerRef: React.RefObject<HTMLDivElement>
 }
 
-function DraggableCard({ card }: DraggableCardProps) {
-  // Track the card's current position in state (separate from the animation values)
-  const currentPositionRef = useRef({
-    x: card.initialX,
-    y: card.initialY,
-    rotation: card.initialRotation,
-  })
-
-  const [{ x, y, rotation, scale }, api] = useSpring(() => ({
-    x: card.initialX,
-    y: card.initialY,
-    rotation: card.initialRotation,
-    scale: 1,
-    config: config.wobbly,
-  }))
-
+function DraggableCard({ card, containerRef }: DraggableCardProps) {
+  // Track position - starts at initial, updates when dragged
+  const [position, setPosition] = useState({ x: card.initialX, y: card.initialY })
+  const [rotation, setRotation] = useState(card.initialRotation) // Now dynamic!
   const [zIndex, setZIndex] = useState(card.zIndex)
-  const cardRef = useRef<HTMLDivElement>(null)
-  const dragOffsetRef = useRef({ x: 0, y: 0 })
-  const lastVelocityRef = useRef({ vx: 0, vy: 0 })
-  const velocityHistoryRef = useRef<Array<{ vx: number; vy: number }>>([])
-  const [transformOrigin, setTransformOrigin] = useState('center center')
+  const [isDragging, setIsDragging] = useState(false)
+  const [dragSpeed, setDragSpeed] = useState(0) // Speed for dynamic shadow
 
-  const bind = useDrag(
-    ({ down, movement: [mx, my], velocity: [vx, vy], direction: [dx, dy], first, xy }) => {
-      // Bring card to front when dragging
-      if (down) {
-        setZIndex(1000)
+  // Track drag state
+  const dragStartRef = useRef<{ x: number; y: number; cardX: number; cardY: number } | null>(null)
+  const grabOffsetRef = useRef<{ x: number; y: number }>({ x: 0, y: 0 }) // Offset from card center where grabbed
+  const baseRotationRef = useRef(card.initialRotation) // Starting rotation
+  const lastMoveTimeRef = useRef<number>(0)
+  const lastMovePositionRef = useRef<{ x: number; y: number }>({ x: 0, y: 0 })
+  const lastLogTimeRef = useRef<number>(0) // Separate throttling for logging
+  const cardRef = useRef<HTMLDivElement>(null) // Reference to card element
 
-        // Calculate drag offset from card center on first touch
-        if (first && cardRef.current) {
-          const cardRect = cardRef.current.getBoundingClientRect()
-          const cardWidth = cardRect.width
-          const cardHeight = cardRect.height
+  const handlePointerDown = (e: React.PointerEvent) => {
+    setIsDragging(true)
+    setZIndex(1000) // Bring to front
+    setDragSpeed(0)
 
-          // xy is in viewport coordinates, convert to position relative to card
-          const clickRelativeToCard = {
-            x: xy[0] - cardRect.left,
-            y: xy[1] - cardRect.top,
-          }
+    // Capture the pointer
+    e.currentTarget.setPointerCapture(e.pointerId)
 
-          // Calculate offset from card center
-          const cardCenterX = cardWidth / 2
-          const cardCenterY = cardHeight / 2
-          const offsetX = clickRelativeToCard.x - cardCenterX
-          const offsetY = clickRelativeToCard.y - cardCenterY
-
-          dragOffsetRef.current = { x: offsetX, y: offsetY }
-
-          // Convert offset to transform-origin (50% + offset as percentage of card size)
-          const originX = 50 + (offsetX / cardWidth) * 100
-          const originY = 50 + (offsetY / cardHeight) * 100
-          const transformOriginValue = `${originX}% ${originY}%`
-
-          console.log(
-            `Drag start: click at (${clickRelativeToCard.x.toFixed(0)}, ${clickRelativeToCard.y.toFixed(0)}) in card, offset from center: (${offsetX.toFixed(0)}, ${offsetY.toFixed(0)}), origin: ${transformOriginValue}`
-          )
-
-          setTransformOrigin(transformOriginValue)
-          velocityHistoryRef.current = []
-        }
-
-        // Smooth velocity by averaging last 3 frames
-        velocityHistoryRef.current.push({ vx, vy })
-        if (velocityHistoryRef.current.length > 3) {
-          velocityHistoryRef.current.shift()
-        }
-
-        const avgVx =
-          velocityHistoryRef.current.reduce((sum, v) => sum + v.vx, 0) /
-          velocityHistoryRef.current.length
-        const avgVy =
-          velocityHistoryRef.current.reduce((sum, v) => sum + v.vy, 0) /
-          velocityHistoryRef.current.length
-
-        // Calculate rotation based on smoothed velocity and drag offset
-        const velocityAngle = Math.atan2(avgVy, avgVx) * (180 / Math.PI)
-        const offsetAngle =
-          Math.atan2(dragOffsetRef.current.y, dragOffsetRef.current.x) * (180 / Math.PI)
-
-        // Card rotates to align with movement direction, offset by where we're grabbing
-        const targetRotation = velocityAngle - offsetAngle + 90
-
-        const speed = Math.sqrt(avgVx * avgVx + avgVy * avgVy)
-
-        // Store smoothed velocity for throw
-        lastVelocityRef.current = { vx: avgVx, vy: avgVy }
-
-        const finalRotation = speed > 0.01 ? targetRotation : currentPositionRef.current.rotation
-
-        api.start({
-          x: currentPositionRef.current.x + mx,
-          y: currentPositionRef.current.y + my,
-          scale: 1.1,
-          rotation: finalRotation,
-          immediate: (key) => key !== 'rotation', // Position immediate, rotation smooth
-          config: { tension: 200, friction: 30 }, // Smoother rotation spring
-        })
-      } else {
-        // On release, reset transform origin to center
-        setTransformOrigin('center center')
-
-        // On release, apply momentum with decay physics
-        const throwVelocityX = lastVelocityRef.current.vx * 1000
-        const throwVelocityY = lastVelocityRef.current.vy * 1000
-
-        // Calculate final rotation based on throw direction
-        const throwAngle = Math.atan2(throwVelocityY, throwVelocityX) * (180 / Math.PI)
-
-        api.start({
-          x: {
-            from: currentPositionRef.current.x + mx,
-            velocity: throwVelocityX,
-            decay: true,
-          },
-          y: {
-            from: currentPositionRef.current.y + my,
-            velocity: throwVelocityY,
-            decay: true,
-          },
-          scale: 1,
-          rotation: throwAngle + 90, // Card aligns with throw direction
-          config: config.wobbly,
-          onChange: (result) => {
-            // Update current position as card settles
-            if (result.value.x !== undefined) {
-              currentPositionRef.current.x = result.value.x
-            }
-            if (result.value.y !== undefined) {
-              currentPositionRef.current.y = result.value.y
-            }
-            if (result.value.rotation !== undefined) {
-              currentPositionRef.current.rotation = result.value.rotation
-            }
-          },
-        })
-      }
-    },
-    {
-      // Prevent scrolling when dragging
-      preventDefault: true,
-      filterTaps: true,
+    // Record where the drag started (pointer position and card position)
+    dragStartRef.current = {
+      x: e.clientX,
+      y: e.clientY,
+      cardX: position.x,
+      cardY: position.y,
     }
-  )
+
+    // Calculate grab offset from card center IN LOCAL COORDINATES (unrotated)
+    if (cardRef.current) {
+      const rect = cardRef.current.getBoundingClientRect()
+      const cardCenterX = rect.left + rect.width / 2
+      const cardCenterY = rect.top + rect.height / 2
+
+      // Screen-space offset from center
+      const screenOffsetX = e.clientX - cardCenterX
+      const screenOffsetY = e.clientY - cardCenterY
+
+      // Convert to local coordinates by rotating by -rotation
+      const currentRotationRad = (rotation * Math.PI) / 180
+      const cosRot = Math.cos(-currentRotationRad)
+      const sinRot = Math.sin(-currentRotationRad)
+
+      grabOffsetRef.current = {
+        x: screenOffsetX * cosRot - screenOffsetY * sinRot,
+        y: screenOffsetX * sinRot + screenOffsetY * cosRot,
+      }
+      console.log(
+        `[GrabPoint] Grabbed at local offset: (${grabOffsetRef.current.x.toFixed(0)}, ${grabOffsetRef.current.y.toFixed(0)})px (screen offset: ${screenOffsetX.toFixed(0)}, ${screenOffsetY.toFixed(0)}px, rotation: ${rotation.toFixed(1)}°)`
+      )
+    }
+
+    // Store the current rotation as the base for this drag
+    baseRotationRef.current = rotation
+
+    // Initialize velocity tracking
+    const now = Date.now()
+    lastMoveTimeRef.current = now
+    lastMovePositionRef.current = { x: e.clientX, y: e.clientY }
+    lastLogTimeRef.current = now
+
+    console.log('[Shadow] Drag started, speed reset to 0')
+  }
+
+  const handlePointerMove = (e: React.PointerEvent) => {
+    if (!isDragging || !dragStartRef.current) return
+
+    // Calculate how far the pointer has moved since drag started
+    const deltaX = e.clientX - dragStartRef.current.x
+    const deltaY = e.clientY - dragStartRef.current.y
+
+    // Calculate velocity for dynamic shadow
+    const now = Date.now()
+    const timeDelta = now - lastMoveTimeRef.current
+
+    if (timeDelta > 0) {
+      // Distance moved since last frame
+      const distX = e.clientX - lastMovePositionRef.current.x
+      const distY = e.clientY - lastMovePositionRef.current.y
+      const distance = Math.sqrt(distX * distX + distY * distY)
+
+      // Speed in pixels per millisecond, then convert to reasonable scale
+      const speed = distance / timeDelta
+      const scaledSpeed = Math.min(speed * 100, 100) // Cap at 100 for reasonable shadow size
+
+      setDragSpeed(scaledSpeed)
+
+      // Log occasionally (every ~200ms) to avoid console spam
+      const timeSinceLastLog = now - lastLogTimeRef.current
+      if (timeSinceLastLog > 200) {
+        console.log(
+          `[Shadow] Speed: ${scaledSpeed.toFixed(1)}, distance: ${distance.toFixed(0)}px, timeDelta: ${timeDelta}ms`
+        )
+        lastLogTimeRef.current = now
+      }
+
+      lastMoveTimeRef.current = now
+      lastMovePositionRef.current = { x: e.clientX, y: e.clientY }
+    }
+
+    // Calculate rotation based on grab point physics
+    // Cross product of grab offset and drag direction determines rotation
+    // If grabbed on left and dragged right → clockwise rotation
+    // If grabbed on right and dragged left → counter-clockwise rotation
+    const crossProduct = grabOffsetRef.current.x * deltaY - grabOffsetRef.current.y * deltaX
+    const rotationInfluence = crossProduct / 500 // Reduced scale factor for more visible rotation
+    const newRotation = baseRotationRef.current + rotationInfluence
+
+    // Clamp rotation to prevent excessive spinning
+    const clampedRotation = Math.max(-45, Math.min(45, newRotation))
+    setRotation(clampedRotation)
+
+    // Log rotation changes occasionally (same throttle as shadow logging)
+    const timeSinceLastLog = now - lastLogTimeRef.current
+    if (timeSinceLastLog > 200) {
+      console.log(
+        `[GrabPoint] Rotation: ${clampedRotation.toFixed(1)}° (influence: ${rotationInfluence.toFixed(1)}°, cross: ${crossProduct.toFixed(0)})`
+      )
+    }
+
+    // Update card position - keep grab point under cursor while rotating
+    // Calculate the rotated grab offset
+    const rotationRad = (clampedRotation * Math.PI) / 180
+    const cosRot = Math.cos(rotationRad)
+    const sinRot = Math.sin(rotationRad)
+
+    // Rotate the grab offset by the current rotation angle
+    const rotatedGrabX = grabOffsetRef.current.x * cosRot - grabOffsetRef.current.y * sinRot
+    const rotatedGrabY = grabOffsetRef.current.x * sinRot + grabOffsetRef.current.y * cosRot
+
+    // Get container bounds for coordinate conversion
+    if (!containerRef.current || !cardRef.current) {
+      // Fallback to simple delta if refs not ready
+      setPosition({
+        x: dragStartRef.current.cardX + deltaX,
+        y: dragStartRef.current.cardY + deltaY,
+      })
+      return
+    }
+
+    const containerRect = containerRef.current.getBoundingClientRect()
+    const cardRect = cardRef.current.getBoundingClientRect()
+
+    // Current cursor position in viewport space
+    const cursorViewportX = e.clientX
+    const cursorViewportY = e.clientY
+
+    // Card center should be at: cursor - rotated grab offset (viewport space)
+    const cardCenterViewportX = cursorViewportX - rotatedGrabX
+    const cardCenterViewportY = cursorViewportY - rotatedGrabY
+
+    // Convert card center from viewport space to container space
+    const cardCenterContainerX = cardCenterViewportX - containerRect.left
+    const cardCenterContainerY = cardCenterViewportY - containerRect.top
+
+    // position.x/y represents translate() which positions the top-left corner
+    // So we need: top-left = center - (width/2, height/2)
+    setPosition({
+      x: cardCenterContainerX - cardRect.width / 2,
+      y: cardCenterContainerY - cardRect.height / 2,
+    })
+  }
+
+  const handlePointerUp = (e: React.PointerEvent) => {
+    setIsDragging(false)
+    dragStartRef.current = null
+
+    console.log('[Shadow] Drag released, speed decaying to 0')
+    console.log(
+      `[GrabPoint] Final rotation: ${rotation.toFixed(1)}° (base was ${baseRotationRef.current.toFixed(1)}°)`
+    )
+
+    // Gradually decay speed back to 0 for smooth shadow transition
+    const decayInterval = setInterval(() => {
+      setDragSpeed((prev) => {
+        const newSpeed = prev * 0.8 // Decay by 20% each frame
+        if (newSpeed < 1) {
+          clearInterval(decayInterval)
+          return 0
+        }
+        return newSpeed
+      })
+    }, 50) // Update every 50ms
+
+    // Release the pointer capture
+    e.currentTarget.releasePointerCapture(e.pointerId)
+  }
+
+  // Calculate dynamic shadow based on drag speed
+  // Base shadow: 0 8px 24px rgba(0, 0, 0, 0.3)
+  // Fast drag: 0 32px 64px rgba(0, 0, 0, 0.6)
+  const shadowY = 8 + (dragSpeed / 100) * 24 // 8px to 32px
+  const shadowBlur = 24 + (dragSpeed / 100) * 40 // 24px to 64px
+  const shadowOpacity = 0.3 + (dragSpeed / 100) * 0.3 // 0.3 to 0.6
+  const boxShadow = `0 ${shadowY}px ${shadowBlur}px rgba(0, 0, 0, ${shadowOpacity})`
 
   return (
-    <animated.div
+    <div
       ref={cardRef}
-      {...bind()}
+      onPointerDown={handlePointerDown}
+      onPointerMove={handlePointerMove}
+      onPointerUp={handlePointerUp}
       style={{
         position: 'absolute',
         left: 0,
         top: 0,
-        transform: to(
-          [x, y, rotation, scale],
-          (x, y, r, s) => `translate(${x}px, ${y}px) rotate(${r}deg) scale(${s})`
-        ),
-        transformOrigin,
+        transform: `translate(${position.x}px, ${position.y}px) rotate(${rotation}deg) scale(${isDragging ? 1.05 : 1})`,
         zIndex,
         touchAction: 'none',
-        cursor: 'grab',
+        cursor: isDragging ? 'grabbing' : 'grab',
+        transition: isDragging ? 'none' : 'transform 0.2s ease-out',
       }}
       className={css({
         userSelect: 'none',
-        _active: {
-          cursor: 'grabbing',
-        },
       })}
     >
       <div
+        style={{
+          boxShadow, // Dynamic shadow based on drag speed
+        }}
         className={css({
           bg: 'white',
           rounded: 'lg',
           p: '4',
-          boxShadow: '0 8px 24px rgba(0, 0, 0, 0.3)',
           display: 'flex',
           flexDirection: 'column',
           alignItems: 'center',
           gap: '2',
           minW: '120px',
           border: '2px solid rgba(0, 0, 0, 0.1)',
-          transition: 'box-shadow 0.2s',
-          _hover: {
-            boxShadow: '0 12px 32px rgba(0, 0, 0, 0.4)',
-          },
+          transition: 'box-shadow 0.1s', // Quick transition for responsive feel
         })}
       >
         {/* Abacus visualization */}
@@ -303,6 +352,6 @@ function DraggableCard({ card }: DraggableCardProps) {
           {card.number}
         </div>
       </div>
-    </animated.div>
+    </div>
   )
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "soroban-monorepo",
-  "version": "4.57.9",
+  "version": "4.63.5",
   "private": true,
   "description": "Beautiful Soroban Flashcard Generator - Monorepo",
   "workspaces": [