Interactive Discovery

Build a full-screen, dark-themed hero section for a geology brand called **Lithos**, using **React 18 + TypeScript + Vite + Tailwind CSS** and **lucide-react** for icons. The signature feature is a **cursor-following spotlight that reveals a second image** through a soft circular mask on top of a base image. Match every detail below exactly.

### Fonts
Add this to the top of `src/index.css`, then `@tailwind base/components/utilities`:
```css
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Playfair+Display:ital,wght@1,400;1,500;1,600&display=swap');
* { font-family: 'Inter', sans-serif; }
.font-playfair { font-family: 'Playfair Display', serif; }
```
- Body/UI font: **Inter**.
- Display/wordmark accent: **Playfair Display, italic**.

### Asset URLs (use these exactly)
- Base image (`BG_IMAGE_1`):
  `https://images.higgs.ai/?default=1&output=webp&url=https%3A%2F%2Fd8j0ntlcm91z4.cloudfront.net%2Fuser_38xzZboKViGWJOttwIXH07lWA1P%2Fhf_20260609_195923_b0ba8ace-1d1d-4f2c-9a28-1ab84b330680.png&w=1280&q=85`
- Reveal image (`BG_IMAGE_2`):
  `https://images.higgs.ai/?default=1&output=webp&url=https%3A%2F%2Fd8j0ntlcm91z4.cloudfront.net%2Fuser_38xzZboKViGWJOttwIXH07lWA1P%2Fhf_20260609_201152_bba90a12-bf12-459f-91f0-51f237dbaf3b.png&w=1280&q=85`

### Layout & structure
Root wrapper: `min-h-screen bg-white tracking-[-0.02em]`, inline `fontFamily: "'Inter', sans-serif"`.

**Section** (`<section>`): `relative w-full overflow-hidden h-screen bg-black`, inline `style={{ height: '100dvh' }}`. Layers, by z-index:
1. **Base image** (`z-10`): `absolute inset-0 bg-center bg-cover bg-no-repeat`, background = `BG_IMAGE_1`.
2. **Reveal layer** (`z-30`): a `RevealLayer` component (see below) showing `BG_IMAGE_2`.
3. **Heading** (`z-50`): `absolute top-[14%] left-0 right-0 flex flex-col items-center text-center px-5 pointer-events-none`. An `<h1>` with `text-white leading-[0.95]` containing two block spans:
   - Line 1: `block font-playfair italic font-normal text-5xl sm:text-7xl md:text-8xl`, inline `letterSpacing: '-0.05em'`, text **"Layers hold"**.
   - Line 2: `block font-normal text-5xl sm:text-7xl md:text-8xl -mt-1`, inline `letterSpacing: '-0.08em'`, text **"tales of time"**.
4. **Bottom-left paragraph** (`z-50`): `hidden sm:block absolute bottom-14 left-10 md:left-14 max-w-[260px]`. `<p className="text-sm text-white/80 leading-relaxed">` — "Every layer of sediment records a chapter of our planet, from ancient seabeds to drifting ash, layered across millions of years beneath us."
5. **Bottom-right block** (`z-50`): `absolute bottom-10 sm:bottom-24 left-5 right-5 sm:left-auto sm:right-10 md:right-14 max-w-full sm:max-w-[260px] flex flex-col items-start gap-4 sm:gap-5`. Contains a `<p className="text-xs sm:text-sm text-white/80 leading-relaxed">` — "Our interactive maps let you peel back the crust to trace how stones, fossils, and deep time combine to shape the ground beneath your feet." — and a **Start Digging** button: `bg-[#e8702a] hover:bg-[#d2611f] text-white text-sm font-medium px-7 py-3 rounded-full transition-all hover:scale-[1.03] active:scale-95 hover:shadow-lg hover:shadow-[#e8702a]/30`.

### The cursor spotlight reveal (core mechanic)
In the parent, define `const SPOTLIGHT_R = 260;` and track the mouse with smoothing:
- Refs: `mouse` (raw), `smooth` (eased), `rafRef`; state `cursorPos` (init `{x:-999,y:-999}`).
- `mousemove` listener stores raw `e.clientX/clientY`.
- A `requestAnimationFrame` loop lerps: `smooth.x += (mouse.x - smooth.x) * 0.1` (same for y), then `setCursorPos`. Clean up listener + cancel RAF on unmount.

`RevealLayer({ image, cursorX, cursorY })`:
- Holds a hidden `<canvas>` (`absolute inset-0 pointer-events-none`, `style={{display:'none'}}`) sized to `window.innerWidth/Height` on mount + resize.
- A reveal `<div>` (`absolute inset-0 bg-center bg-cover bg-no-repeat z-30 pointer-events-none`) with the reveal image as background.
- On every render: clear canvas, build a **radial gradient** at `(cursorX, cursorY)` from radius 0 → `SPOTLIGHT_R` with stops:
  `0 → rgba(255,255,255,1)`, `0.4 → 1`, `0.6 → 0.75`, `0.75 → 0.4`, `0.88 → 0.12`, `1 → 0`.
  Fill an arc of radius `SPOTLIGHT_R` with it. Then `canvas.toDataURL()` and apply it as `maskImage`/`webkitMaskImage` on the reveal div with `maskSize: '100% 100%'`. This makes the second image visible only inside the soft glowing circle that trails the cursor.

### Navigation (fixed, over hero)
`<nav className="fixed top-0 left-0 right-0 z-[100] flex items-center justify-between p-4 sm:p-5">`:
- **Left**: an inline SVG logo (26×26, viewBox `0 0 256 256`, `fill="#ffffff"`, path `M 256 256 L 128 256 L 0 128 L 128 128 Z M 256 128 L 128 128 L 0 0 L 128 0 Z`) + wordmark `<span className="text-white text-2xl font-playfair italic">Lithos</span>`.
- **Center pill** (`hidden md:flex absolute left-1/2 -translate-x-1/2 bg-white/20 backdrop-blur-md border border-white/30 rounded-full px-2 py-2 items-center gap-1`): buttons **Course** (active: full white text), then **Field Guides, Geology, Plans, Live Tour** (`text-white/80 ... hover:bg-white/20 hover:text-white transition-colors`, `px-4 py-1.5 rounded-full text-sm font-medium`).
- **Right (desktop)**: `hidden md:block bg-white text-gray-900 text-sm font-semibold px-6 py-2.5 rounded-full hover:bg-gray-100` — **Sign Up**.

### Animations (premium, on load)
Add to `index.css`:
```css
@keyframes heroReveal { 0%{opacity:0;transform:translateY(28px);filter:blur(12px)} 100%{opacity:1;transform:translateY(0);filter:blur(0)} }
@keyframes heroFadeUp { 0%{opacity:0;transform:translateY(20px)} 100%{opacity:1;transform:translateY(0)} }
@keyframes heroZoom { 0%{transform:scale(1.12)} 100%{transform:scale(1)} }
.hero-anim { opacity:0; animation-fill-mode:forwards; animation-timing-function:cubic-bezier(0.16,1,0.3,1); }
.hero-reveal { animation-name:heroReveal; animation-duration:1.1s; }
.hero-fade { animation-name:heroFadeUp; animation-duration:1s; }
.hero-zoom { animation:heroZoom 1.8s cubic-bezier(0.16,1,0.3,1) forwards; }
@media (prefers-reduced-motion: reduce){ .hero-anim,.hero-zoom{ animation:none; opacity:1; } }
```
Apply:
- Base image div → add `hero-zoom` (slow Ken Burns zoom-out).
- Heading line 1 → `hero-anim hero-reveal`, inline `animationDelay: '0.25s'`; line 2 → same with `'0.42s'` (blur-rise, staggered).
- Bottom-left paragraph wrapper → `hero-anim hero-fade`, `animationDelay: '0.7s'`.
- Bottom-right wrapper → `hero-anim hero-fade`, `animationDelay: '0.85s'`.

### Responsiveness
- Heading scales `text-5xl` → `sm:text-7xl` → `md:text-8xl`.
- Center nav pill and desktop Sign Up are `hidden` below `md`; the mobile hamburger is `md:hidden`.
- Bottom-left paragraph is `hidden sm:block`; bottom-right block is full-width on mobile (`left-5 right-5`) and right-anchored from `sm`.
- Use `100dvh` so mobile browser chrome doesn't clip the section.