feat: launch LLM Atlas research course

src/components/SiteHeader.astro

@@ -0,0 +1,50 @@
+---
+interface Props {
+  active?: string;
+}
+
+const { active = "" } = Astro.props;
+const items = [
+  { id: "home", href: "/", label: "首页" },
+  { id: "roadmap", href: "/roadmap/", label: "学习地图" },
+  { id: "k3", href: "/k3/", label: "K3 解剖" },
+  { id: "deepseek", href: "/deepseek/", label: "DeepSeek" },
+  { id: "foundations", href: "/foundations/", label: "基础原理" },
+  { id: "papers", href: "/papers/", label: "论文库" },
+  { id: "progress", href: "/progress/", label: "进度" },
+];
+---
+
+<header class="site-header" id="top">
+  <a class="wordmark" href="/" aria-label="LLM Atlas 首页">
+    <span class="wordmark-mark">L/A</span>
+    <span class="wordmark-copy">
+      <b>LLM ATLAS</b>
+      <small>FROM FIRST PRINCIPLES TO KIMI K3</small>
+    </span>
+  </a>
+  <nav class="top-nav" aria-label="主要导航">
+    {items.map((item) => (
+      <a href={item.href} aria-current={active === item.id ? "page" : undefined}>{item.label}</a>
+    ))}
+  </nav>
+  <div class="header-meta">
+    <span>RESEARCH · 2026</span>
+    <button id="menu-toggle" class="menu-toggle" type="button" aria-expanded="false" aria-controls="mobile-nav">目录</button>
+  </div>
+  <nav id="mobile-nav" class="mobile-nav" aria-label="移动导航">
+    {items.map((item) => (
+      <a href={item.href} aria-current={active === item.id ? "page" : undefined}>{item.label}</a>
+    ))}
+  </nav>
+</header>
+
+<script>
+  const toggle = document.querySelector<HTMLButtonElement>("#menu-toggle");
+  const nav = document.querySelector<HTMLElement>("#mobile-nav");
+  toggle?.addEventListener("click", () => {
+    const open = toggle.getAttribute("aria-expanded") === "true";
+    toggle.setAttribute("aria-expanded", String(!open));
+    nav?.toggleAttribute("data-open", !open);
+  });
+</script>