diff --git a/index.html b/index.html
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+++ b/index.html
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-Hi World
+<!doctype html>
+<html lang="en">
+<head>
+<meta charset="utf-8"/>
+<meta name="viewport" content="width=device-width,initial-scale=1,viewport-fit=cover"/>
+<title>Hi Language — Symbolic, World‑First</title>
+
+<!-- Tailwind (for layout/spacing/utility) -->
+<script src="https://cdn.tailwindcss.com"></script>
+
+<!-- GitHub Markdown skin + HLJS GitHub theme -->
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/github-markdown-css@5.8.1/github-markdown-light.min.css"/>
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.11.1/build/styles/github.min.css"/>
+
+<style>
+:root{color-scheme:light}
+html,body{height:100%}
+.no-scrollbar::-webkit-scrollbar{display:none}
+.no-scrollbar{-ms-overflow-style:none;scrollbar-width:none}
+.markdown-body{font-size:16px;line-height:1.65}
+.markdown-body :is(h1,h2,h3){scroll-margin-top:84px}
+.markdown-body pre{overflow:auto}
+.copy-btn{position:absolute;top:.5rem;right:.5rem;font-size:.75rem;padding:.25rem .5rem;border-radius:.5rem;background:#0f172a;color:#fff;opacity:.9}
+.copy-btn:hover{opacity:1}
+.toc-link{display:block;padding:.5rem .75rem;border-radius:.75rem}
+.toc-link:hover{background:#f3f4f6}
+.toc-active{background:#eef2ff}
+.brand-dot{display:inline-flex;align-items:center;justify-content:center;height:28px;width:28px;border-radius:9999px;background:#0f172a;color:#fff}
+header{backdrop-filter:saturate(180%) blur(8px)}
+@media (min-width:1024px){
+  #contentWrap{grid-template-columns: 280px 1fr}
+  #sidebarLeft{position:sticky;top:64px;height:calc(100dvh - 64px);transform:none!important}
+  #sidebarOverlay{display:none!important}
+}
+</style>
+
+<!-- Alpine + Lucide + MarkdownIt + HLJS -->
+<script defer src="https://unpkg.com/alpinejs"></script>
+<script src="https://unpkg.com/lucide@latest"></script>
+<script src="https://cdn.jsdelivr.net/npm/markdown-it@14.1.0/dist/markdown-it.min.js"></script>
+<script src="https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@11.11.1/build/highlight.min.js"></script>
+</head>
+<body class="bg-white text-gray-900 selection:bg-black/10" x-data="{open:false}" @keydown.escape="open=false">
+  <!-- Topbar -->
+  <header class="sticky top-0 z-20 bg-white/85 border-b border-gray-200">
+    <div class="mx-auto max-w-6xl px-4 py-3 grid grid-cols-3 items-center">
+      <button class="h-8 w-8 rounded-xl bg-gray-100 hover:bg-gray-200 active:scale-[.99] transition flex items-center justify-center"
+              title="Menu" @click="open=true">
+        <i data-lucide="panel-left" class="h-5 w-5"></i>
+      </button>
+      <div class="justify-self-center text-base font-semibold tracking-tight select-none pointer-events-none">Hi</div>
+      <div class="justify-self-end"></div>
+    </div>
+  </header>
+
+  <!-- Content -->
+  <div id="contentWrap" class="mx-auto max-w-6xl lg:grid relative">
+    <!-- Left sidebar -->
+    <aside id="sidebarLeft" class="fixed inset-y-0 left-0 z-50 w-72 max-w-[85vw] bg-white border-r border-gray-200 shadow-xl transform -translate-x-full transition-transform duration-200 ease-out lg:static lg:shadow-none lg:w-auto">
+      <div class="p-3 border-b flex items-center gap-3">
+        <span class="brand-dot">✺</span>
+        <div class="min-w-0">
+          <div class="text-sm font-semibold truncate">Hi</div>
+          <div class="text-xs text-gray-500 truncate">A symbolic language for everyone</div>
+        </div>
+      </div>
+      <nav id="toc" class="p-2 overflow-y-auto no-scrollbar space-y-1 text-sm"></nav>
+      <div class="p-3 border-t text-xs text-gray-500">
+        <span>Still in development — more coming soon.</span>
+      </div>
+    </aside>
+    <div id="sidebarOverlay" class="fixed inset-0 z-40 bg-black/20 hidden" :class="open?'':'hidden'" @click="open=false"></div>
+    <script>
+      document.addEventListener('alpine:init',()=>{Alpine.effect(()=>{const a=document.getElementById('sidebarLeft');if(!a)return;a.style.transform=Alpine.store('open')?'translateX(0)':''})})
+    </script>
+
+    <!-- Main -->
+    <main id="main" class="min-h-[calc(100dvh-64px)]">
+      <section id="suneHtml" class="markdown-body px-4 sm:px-6 lg:px-10 py-8"></section>
+    </main>
+  </div>
+
+<script>
+document.addEventListener('DOMContentLoaded',()=>{
+
+  const md = window.markdownit({html:false,linkify:true,typographer:true,breaks:true})
+  const slug = s=>s.toLowerCase().trim()
+    .replace(/["'’]/g,'')
+    .replace(/&/g,' and ')
+    .replace(/[^a-z0-9]+/g,'-')
+    .replace(/^-+|-+$/g,'')||'sec'
+  const $ = s=>document.querySelector(s)
+  const $$ = s=>[...document.querySelectorAll(s)]
+  const icons = ()=>window.lucide&&lucide.createIcons()
+
+  const DOC = String.raw`
+# Hi
+A new, symbolic programming language inspired by JavaScript — but with a "corely" symbolic design. Fewer keywords, more universal symbols. Hi aims to be approachable worldwide.
+
+> Tip: All code snippets below use JavaScript syntax highlighting while Hi is still evolving.
+
+## Hello, world
+\`\`\`js
+// This is hello world in Hi
+_("Hi world")
+\`\`\`
+
+## Symbols you’ll meet first
+- \`: \` declaration
+- \`= \` assignment
+- \`{ ... }\` a Block (both object and function)
+- \`#name\` private field in a Block
+- \`_("...")\` print (show text)
+- \`? :\` conditional (blocks return last value)
+- \`* { ... }\` loop body
+- \`>>\` continue, \`^\` break
+
+Blocks are always both an object and a function. They can hold properties and executable code at once.
+
+## Blocks
+### Function Block
+\`\`\`js
+sayHi: {
+  _("Hi")
+}
+sayHi()       // call the Block like a function
+\`\`\`
+
+### Object Block
+\`\`\`js
+player: {
+  name: "Orion" // public
+  #hp: 100       // private
+}
+_(player.name)   // "Orion"
+\`\`\`
+
+### Hybrid Block
+\`\`\`js
+counter: {
+  #value: 0
+  inc: {
+    value = value + 1
+    _("The count is now: " + value)
+  }
+}
+
+counter.inc()  // The count is now: 1
+counter.inc()  // The count is now: 2
+\`\`\`
+
+### Parameters
+\`\`\`js
+withParams: (str) {
+  _(str)
+}
+withParams("Hola") // prints Hola
+\`\`\`
+
+## Truthiness and equality
+Hi emphasizes clear truthiness:
+\`\`\`js
+0    // falsy (official false)
+!0   // truthy (official true)
+4    // truthy
+""   // falsy  (truthy if non-empty)
+{}   // falsy  (truthy if contains fields or code ran)
+[]   // falsy  (truthy if non-empty)
+-0   // falsy / null / undefined equivalent-ish in Hi's model
+
+// Equality is simple:
+==   // equivalent to JS ===
+\`\`\`
+
+## Conditionals
+Blocks return their last value (like Rust expressions).
+\`\`\`js
+// if
+(cond) ? { _("yes") }
+
+// if / else
+(cond) ? { _("yes") } : { _("no") }
+
+// as an expression
+tern: (cond) ? { "A" } : { "B" }
+_(tern) // prints A or B
+
+// else-if chain
+score: 85
+grade: (score > 90) ? { "A" }
+     : (score > 80) ? { "B" }
+     :                 { "C" }
+_(grade) // "B"
+\`\`\`
+
+## Arrays
+\`\`\`js
+primes: [2, 3, 5, 7]
+
+// Access
+firstPrime: primes[0]
+
+// Mutation
+primes[0] = 1
+_(primes)  // [1, 3, 5, 7]
+\`\`\`
+
+## Loops
+Use \`* { ... }\` after a loop header. \`>>\` continues, \`^\` breaks.
+\`\`\`js
+// for
+(i: 0; i < 5; i = i + 1) * {
+  _(i)
+  (i == 2) ? { >> } // continue at i==2 (skip rest)
+}
+
+// while
+(done: !0) * {
+  // ...
+  ^ // break
+}
+\`\`\`
+
+## Putting it together
+Here are a few small programs that connect the dots.
+
+### FizzBuzz
+\`\`\`js
+fizzbuzz: (n) {
+  (n % 15 == 0) ? { "FizzBuzz" }
+: (n %  3 == 0) ? { "Fizz" }
+: (n %  5 == 0) ? { "Buzz" }
+:                 { n }
+}
+
+(i: 1; i <= 16; i = i + 1) * {
+  _( fizzbuzz(i) )
+}
+\`\`\`
+
+### A tiny accumulator
+\`\`\`js
+acc: {
+  #sum: 0
+  add: (x) { sum = sum + x }
+  get: { sum }
+}
+
+acc.add(6)
+acc.add(7)
+_( acc.get() ) // 13
+\`\`\`
+
+### Recursive example
+\`\`\`js
+fib: (n) {
+  (n < 2) ? { n } : { fib(n-1) + fib(n-2) }
+}
+_( fib(6) ) // 8
+\`\`\`
+
+## Design philosophy
+Hi keeps its core "mostly symbols" to be friendlier across languages and writing systems. Keywords appear where they’re practical; everywhere else, symbols do the heavy lifting. The goal: an approachable, expressive language for the whole world.
+
+—
+
+Hi is in active development. Expect changes, clarifications, and more features, examples, and tooling soon. Stay tuned!
+`
+
+  // Render docs
+  const root = $('#suneHtml')
+  root.innerHTML = md.render(DOC)
+
+  // Add ids to headings + build TOC
+  const heads = $$('h1, h2, h3', root) // query relative later
+  const tocEl = $('#toc')
+  const items=[]
+  $$('#suneHtml h1, #suneHtml h2, #suneHtml h3').forEach(h=>{
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+    const id = h.id || slug(h.textContent||'')
+    h.id = id
+    // small anchor
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+    a.href = '#'+id
+    a.className='ml-2 align-middle text-gray-300 hover:text-gray-500'
+    a.innerHTML = '<svg data-lucide="link-2" class="inline h-3.5 w-3.5"></svg>'
+    h.appendChild(a)
+
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+  })
+
+  tocEl.innerHTML = [
+    '<div class="px-3 py-2 text-xs font-medium text-gray-500 uppercase tracking-wide">Contents</div>',
+    ...items.map(x=>{
+      const pad = x.level===1?'pl-3':x.level===2?'pl-5':'pl-8'
+      return `<a class="toc-link ${pad}" href="#${x.id}" data-id="${x.id}">${x.text}</a>`
+    })
+  ].join('')
+
+  // Scroll handling
+  tocEl.addEventListener('click',e=>{
+    const a=e.target.closest('a[href^="#"]'); if(!a) return
+    e.preventDefault()
+    const id=a.getAttribute('href').slice(1)
+    const el=document.getElementById(id); if(!el) return
+    window.scrollTo({top:el.getBoundingClientRect().top+window.scrollY-72,behavior:'smooth'})
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+  })
+
+  // Scrollspy
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+  const map = Object.fromEntries(links.map(a=>[a.dataset.id,a]))
+  const io = new IntersectionObserver(es=>{
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+        map[id].classList.add('toc-active')
+      }
+    })
+  },{rootMargin:'-60px 0px -70% 0px',threshold:1e-3})
+  $$('#suneHtml h1, #suneHtml h2').forEach(h=>io.observe(h))
+
+  // Highlight + small copy buttons
+  hljs.highlightAll()
+  $$('#suneHtml pre>code').forEach(code=>{
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+    pre.style.position='relative'
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+    btn.className='copy-btn'
+    btn.innerHTML='<svg data-lucide="copy" class="inline h-3.5 w-3.5 mr-1 -mt-0.5"></svg>Copy'
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+        await navigator.clipboard.writeText(code.innerText)
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+  })
+
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+
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+  icons()
+})
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+</body>
+</html>
