# Cascade: animation library for Unity UI Toolkit > Cascade animates Unity UI Toolkit VisualElements (UXML/USS, UIElements) at runtime: tweens, easing, springs, stagger, enter/exit and screen transitions, hover/press/focus, named states, a no-code UI Animator and validated JSON animation sequences. Unity 6000.0+, pure C#, no dependencies. Cascade Lite is free and MIT licensed (https://assetstore.unity.com/packages/slug/394764); Cascade Pro adds springs, stagger, transitions, interactions, variants, the UI Animator, JSON sequences and effects (https://assetstore.unity.com/packages/slug/394760). Agent skill: npx skills add twitchedd/cascade-skill ## Docs - [Overview](https://twitchedd.github.io/cascade/docs/): Documentation for Cascade, a runtime animation library for Unity UI Toolkit (UIElements, UXML/USS): tweens, easing, springs, stagger, enter/exit and screen transitions. Free Lite tier, MIT licensed. - [Getting started](https://twitchedd.github.io/cascade/docs/getting-started.html): Install Cascade from the Unity Asset Store, open the demo scene, and write your first UI Toolkit animation: fade, move, sequence, cancel and await a VisualElement animation. - [Animate a VisualElement](https://twitchedd.github.io/cascade/docs/animate-visualelement.html): Four ways to animate a VisualElement in Unity UI Toolkit at runtime: USS transitions, the panel scheduler, the experimental animation API, and a tween library such as Cascade. Code and trade-offs for each. - [Spring animation](https://twitchedd.github.io/cascade/docs/spring-animation.html): Add physics spring animation to Unity UI Toolkit VisualElements with Cascade: presets, custom springs by feel (response and bounce), springs on hover, and interruptions that keep their momentum. - [Stagger a list](https://twitchedd.github.io/cascade/docs/stagger-list.html): Animate a UI Toolkit list or menu so items enter one after another. Cascade's AnimateEach and Stagger, how to choose the step, and how to schedule what comes after a staggered group. - [Transitions](https://twitchedd.github.io/cascade/docs/transitions.html): Show and hide UI Toolkit panels with animated enter and exit transitions, and swap screens with a crossfade: toasts, modal dialogs, tabs and menus with Cascade's Show, Hide and SwapTo. - [Recipes](https://twitchedd.github.io/cascade/docs/recipes.html): Copy-and-paste Unity UI Toolkit animation patterns with Cascade: hover/press/focus feedback, an accordion, named states, async sequences, loops, additive nudges, reduced motion, and the mistakes that break UI animation. - [No-code: UI Animator](https://twitchedd.github.io/cascade/docs/no-code.html): Add entrance, hover, press and focus animations to a Unity UI Toolkit screen from the Inspector, with live preview in edit mode, using Cascade's UI Animator component and presets. No C# required. - [Shadow, glow and filters](https://twitchedd.github.io/cascade/docs/effects.html): Add a soft drop shadow or outer glow to a Unity UI Toolkit element with Cascade's mesh-based DropShadowElement, and animate USS filter blur and tint on Unity 6.3 and later. - [Coming from Framer Motion](https://twitchedd.github.io/cascade/docs/framer-motion.html): Coming from web animation? Every Framer Motion idea (animate, initial, transition, spring, variants, whileHover, staggerChildren, AnimatePresence) mapped to its Cascade equivalent in Unity UI Toolkit. - [Performance and lifecycle](https://twitchedd.github.io/cascade/docs/performance.html): How Cascade animates Unity UI Toolkit without per-frame garbage, which properties are cheap to animate, how animations stop when elements leave the panel, how replacing and per-property stopping work, and how to measure load. - [AI assistants and skill](https://twitchedd.github.io/cascade/docs/ai-and-skill.html): Let Claude Code, Cursor, Codex or Copilot write Unity UI Toolkit animations with Cascade. Install the open agent skill, use the AI guide that ships in the package, and generate validated JSON animation sequences. - [Easing curves](https://twitchedd.github.io/cascade/docs/easing.html): All 28 easing functions in Cascade for Unity UI Toolkit, drawn as curves, with which to use for entrances, exits, pop-ins and loops, plus custom AnimationCurve easing. - [API reference](https://twitchedd.github.io/cascade/docs/api.html): Every public type and method in Cascade, the animation library for Unity UI Toolkit: Animate, TweenSequence verbs, easing, springs, stagger, transitions, interactions, variants, settings, JSON sequences and effects. Lite and Pro marked. - [FAQ](https://twitchedd.github.io/cascade/docs/faq.html): Answers about Cascade for Unity UI Toolkit: Unity versions, uGUI support, Lite vs Pro, upgrading, licensing, platforms, performance, USS transitions, and getting help. ## Examples - [Cascade Audio Studio (play in browser)](https://twitchedd.itch.io/cascade-audio-studio): A music player built in Unity UI Toolkit and animated with Cascade, where the whole UI follows the song: fire, lasers and rain driven by beat detection and a loudness level, a scratchable record, mixer faders and pause that freezes every effect. - [Audio-reactive UI in Unity UI Toolkit (write-up)](https://medium.com/@dldesing/audio-reactive-ui-in-unity-ui-toolkit-fire-lasers-and-rain-that-follow-the-music-f18d74d7385a): How the Audio Studio drives UI Toolkit effects from music with Cascade tweens: one Value tween re-themes the screen, looping tweens for fire, lasers and rain, beat and loudness signals, a turntable motor, and the bugs fixed along the way. - [Cascade Blocks (play in browser)](https://twitchedd.itch.io/cascade-blocks): A falling-block game whose UI motion is all Cascade: menu stagger, screen transitions, line-clear sweep and score count-up.