diff --git a/layouts/index.html b/layouts/index.html
index 7809021..53ae3c9 100644
--- a/layouts/index.html
+++ b/layouts/index.html
@@ -21,7 +21,7 @@
       <h1 class="head">NumPy-style n-dimensional arrays in pure Go.<br><span class="accent">float64, multicore + SIMD.</span></h1>
       <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/">Read the documentation →</a>
+        <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>5</b> SIMD targets</span><span><b>CGO=0</b> no BLAS shim</span></div>
diff --git a/layouts/partials/icons/book.html b/layouts/partials/icons/book.html
new file mode 100644
index 0000000..cf1e882
--- /dev/null
+++ b/layouts/partials/icons/book.html
@@ -0,0 +1,5 @@
+{{- /* Octicons "book" (16 px), primer/octicons @primer/octicons-react@19.40.0, copied verbatim, MIT,
+     (c) GitHub Inc.: the licence is OCTICONS-LICENSE beside this file.
+     currentColor follows the button in light and dark; aria-hidden, since
+     the button's text already says where it leads. */ -}}
+<svg class="icon" xmlns="http://www.w3.org/2000/svg" width="16" height="16" viewBox="0 0 16 16" fill="currentColor" aria-hidden="true" focusable="false"><path d="M0 1.75A.75.75 0 0 1 .75 1h4.253c1.227 0 2.317.59 3 1.501A3.743 3.743 0 0 1 11.006 1h4.245a.75.75 0 0 1 .75.75v10.5a.75.75 0 0 1-.75.75h-4.507a2.25 2.25 0 0 0-1.591.659l-.622.621a.75.75 0 0 1-1.06 0l-.622-.621A2.25 2.25 0 0 0 5.258 13H.75a.75.75 0 0 1-.75-.75Zm7.251 10.324.004-5.073-.002-2.253A2.25 2.25 0 0 0 5.003 2.5H1.5v9h3.757a3.75 3.75 0 0 1 1.994.574ZM8.755 4.75l-.004 7.322a3.752 3.752 0 0 1 1.992-.572H14.5v-9h-3.495a2.25 2.25 0 0 0-2.25 2.25Z"/></svg>
\ No newline at end of file
diff --git a/layouts/partials/styles.html b/layouts/partials/styles.html
index d50c2a8..3499b6a 100644
--- a/layouts/partials/styles.html
+++ b/layouts/partials/styles.html
@@ -104,6 +104,7 @@
   .theme-toggle:hover{border-color:var(--ghost-border-hover)}
   .btn{display:inline-flex;align-items:center;gap:8px;font-weight:700;font-size:14px;padding:11px 18px;
     border-radius:12px;border:1px solid transparent;transition:.15s}
+  .btn .icon{flex:none}
   {{/* ⛔ `.btn.btn-primary`, not `.btn-primary`. Further down this file sits
        `.lm a{color:inherit}`, and `.lm a` is a class AND an element -- (0,1,1)
        -- which BEATS a single class. So the primary button, which is an <a>,