Build a React application called "Posthumentor", an AI mentorship platform that lets users get advice from historically accurate AI versions of great minds (like Steve Jobs, Marcus Aurelius, etc.).

Design System & Aesthetic (CRITICAL)

Use an "Editorial Aesthetic" (think high-end print magazine or newspaper).

• Colors: Use a light, paper-like background (bg-[#F8F5F1]) and dark ink text (text-[#1A1A1A]). Use a muted gray for secondary text/borders (#E5E5E5 or black with low opacity).
• Typography: Heavily mix Serif and Sans-Serif. Use a classic Serif font (like Playfair Display or Georgia) for all large headings, quotes, and titles. Use a clean Sans-Serif (like Inter or Helvetica) for body text, buttons, and UI elements.
• Styling Details: Use sharp corners (no rounded borders). Use thin, 1px borders for separation. For small labels, use very small text (10px-12px), uppercase, with wide letter spacing (e.g., tracking-[2px]).
• Animations: Use Framer Motion for smooth, subtle fade-ins and slide-ups.

App Flow & State

The app should have 3 main views managed by state: landing, dashboard, and chat. Include a hardcoded default user profile object: { goals: 'Scale to $1M ARR', challenges: 'Hiring', businessStage: 'Early Traction', personalityType: 'Analytical' }.

View 1: Landing Page

• Nav: Logo "Posthumentor" (serif, italic) on the left. "Try Demo" button on the right (thin border, hover inverts colors).
• Hero:
  • Small uppercase label: "THE ULTIMATE BOARD OF ADVISORS".
  • Massive serif headline: "Mentorship from [line break] history's greatest [line break] minds." (Make "history's greatest" italic).
  • Subheadline: "Get 1-on-1 coaching from historically accurate AI versions of Jobs, Buffett, Aurelius, and more."
  • CTA Button: "TRY THE DEMO" with a right arrow icon. Clicking this changes the state to dashboard.
• Features Grid: 3 columns below the hero. "01. Context Aware", "02. Live Sessions", "03. Accountability" with short descriptions.

View 2: Dashboard

A two-column layout (Sidebar + Main Content).

• Sidebar (Left, fixed width):
  • Logo at the top.
  • Navigation links: "Hall of Mentors", "Active Sessions", "Your Evolution". The active link should be Serif, italic, and larger. Inactive links should be Sans-serif and smaller.
  • Bottom of sidebar: Display the user's "Founder Profile" stage.
• Main Content (Right, scrollable):
  • Mentors Tab: A grid of mentor cards. Mock up 3 mentors (e.g., Steve Jobs, Marcus Aurelius, Warren Buffett). Cards should have a thin border, the mentor's name (serif), title (small uppercase), a short quote, and an "Enter the Studio" button at the bottom. Clicking a card changes the state to chat and sets the active mentor.
  • History Tab: A list of past sessions with date, topic, and an action item.
  • Evolution Tab: Display the user's hardcoded profile data (Goals, Challenges, etc.) in a clean, editorial layout.

View 3: Chat Session

A full-screen chat interface.

• Header: Sticky top. "Back to Academy" button on the left. Mentor's name (serif) and title (small uppercase) on the right.