Specimen Flip Card

Build a "Specimen Flip Card" React component.

CONCEPT: A type-foundry specimen card: front shows a single huge glyph 'Ag' and font name; clicking flips the card 180° on the Y axis to reveal weights, sizes and a pangram on the back.

LAYOUT & CONTENT:
- Card 260x320, cream front with charcoal border; back in cobalt with cream text.
- Front: 'Ag' at 9rem, font name 'Norm Grotesk', a small 'Flip ↻' hint. Back: list of weights (Light 300 → Black 900) with 1px rules and the pangram 'Sphinx of black quartz, judge my vow.'

INTERACTIONS & MOTION:
- Container perspective 1000px; inner wrapper animates rotateY 0 ↔ 180 with spring stiffness 260 damping 20 (visible overshoot).
- Both faces use backface-visibility hidden; back face pre-rotated 180deg.
- Hover (not flipped): lift with rotateX 4deg. The card is a <button> with aria-pressed.

DESIGN SYSTEM (non-negotiable):
- Palette: paper background #FAF9F6, deep charcoal #121212 for text and 1px borders, ONE warm accent: cobalt #1D4ED8 or terracotta #D9534F. Secondary surface #F2EFE8.
- Typography: Swiss / editorial. A tight grotesk for UI (Instrument Sans, Inter Tight or similar) with negative tracking on display sizes; an italic serif (Instrument Serif) used sparingly for one emphasized word.
- NO dark-mode neon, NO glow, NO glassmorphism, NO backdrop blur, NO purple-to-blue gradients, NO emoji icons. Solid fills, hairline rules, honest shadows (hard offset or none).
- Motion: Framer Motion with spring physics (type: "spring", stiffness 300-500, damping 20-35). Animate transform and opacity only. Respect prefers-reduced-motion via useReducedMotion().
- Icons: lucide-react, 1.5px stroke.
- Accessibility: real <button>/<a>/<label> elements, visible focus ring (2px cobalt, 3px offset), keyboard operable, aria attributes where state changes.

OUTPUT: one self-contained React component file (Tailwind CSS v4 utility classes, framer-motion, lucide-react), no external images, default export, ready to paste into a Next.js App Router page with "use client".