diff --git a/layouts/index.html b/layouts/index.html
index ecdf8ed..ba34514 100644
--- a/layouts/index.html
+++ b/layouts/index.html
@@ -13,8 +13,8 @@
     <a class="brand" href="/"><img class="glyph" src="/img/logo.svg" width="32" height="32" alt="go-ndarray logo"> go-ndarray</a>
     <nav><a href="#features">Why</a><a href="#check">Example</a><a href="#api">API</a><a href="#repos">Repositories</a><a href="/playground/">Playground</a></nav>
     {{ partial "theme-toggle.html" . }}
-    <a class="btn btn-ghost" href="https://github.com/go-ndarray">{{ partial "icons/github.html" . }}GitHub</a>
   </div></header>
+  {{ partial "fork-ribbon.html" "https://github.com/go-ndarray/ndarray" }}
 
   <div class="hero"><div class="wrap">
     <div>
@@ -22,7 +22,6 @@ <h1 class="head">NumPy-style n-dimensional arrays in pure Go.<br><span class="ac
       <p class="sub"><b>go-ndarray</b> is the <code>numpy</code> equivalent for Go: a float64 n-dimensional array with creation routines, <b>strided views that share data</b>, broadcasting elementwise ops and ufuncs, reductions (incl. arg / cumulative / clip / where), manipulation, and linear algebra (a panel-packed, cache-blocked GEMM) — all in <b>pure Go, with cgo disabled</b>.</p>
       <div class="cta">
         <a class="btn btn-primary" href="https://go-ndarray.github.io/docs/">{{ partial "icons/book.html" . }}Read the documentation →</a>
-        <a class="btn btn-ghost" href="https://github.com/go-ndarray/ndarray">{{ partial "icons/github.html" . }}Browse the source</a>
       </div>
       <div class="trust"><span><b>{{ len .Site.Params.families }}</b> API families, NumPy's names</span><span><b>6</b> SIMD targets</span><span><b>CGO=0</b> no BLAS shim</span></div>
     </div>
diff --git a/layouts/partials/fork-ribbon.html b/layouts/partials/fork-ribbon.html
new file mode 100644
index 0000000..3ef81c6
--- /dev/null
+++ b/layouts/partials/fork-ribbon.html
@@ -0,0 +1,5 @@
+{{/* The "Fork me on GitHub" corner ribbon (github.blog, 2008), drawn in CSS
+     with the brand gradient instead of the original PNGs, so it follows the
+     theme. It replaces the nav bar's GitHub button. Called with the
+     repository URL: {{ partial "fork-ribbon.html" "https://github.com/o/r" }} */}}
+<div class="fork-ribbon"><a href="{{ . }}" aria-label="Fork me on GitHub">Fork me on GitHub</a></div>
diff --git a/layouts/partials/styles.html b/layouts/partials/styles.html
index 3499b6a..becc672 100644
--- a/layouts/partials/styles.html
+++ b/layouts/partials/styles.html
@@ -115,6 +115,17 @@
   .btn-primary:hover{transform:translateY(-1px)}
   .btn.btn-ghost{border-color:var(--line);color:var(--ink);background:var(--surface-2)}
   .btn-ghost:hover{border-color:var(--ghost-border-hover)}
+  {{/* The fork ribbon sits over the page's top-right corner and scrolls away
+       with the page; the nav bar keeps clear of it until the window is wide
+       enough for the 1120px column to stop short of the corner. */}}
+  .fork-ribbon{position:absolute;top:0;right:0;width:150px;height:150px;overflow:hidden;z-index:30;pointer-events:none}
+  .fork-ribbon a{position:absolute;top:48px;right:-36px;width:200px;padding:7px 0;transform:rotate(45deg);
+    background:var(--grad);color:#fff;text-align:center;font-weight:700;font-size:13px;letter-spacing:.02em;
+    box-shadow:0 4px 12px -4px rgba(0,0,0,.45);outline:1px dashed rgba(255,255,255,.55);outline-offset:-4px;pointer-events:auto}
+  .fork-ribbon a:hover{filter:brightness(1.08)}
+  .fork-ribbon a:focus-visible{outline:2px solid #fff;outline-offset:-4px}
+  @media(max-width:1420px){.nav .wrap{padding-right:112px}}
+  @media(max-width:600px){.fork-ribbon{width:112px;height:112px}.fork-ribbon a{top:34px;right:-52px;font-size:11px;padding:5px 0}.nav .wrap{padding-right:84px}}
   /* hero */
   .hero{padding:74px 0 30px;background:
     radial-gradient(900px 380px at 78% -8%,{{ $wash | safeCSS }},transparent 60%),