Replace hero card logo with the inheritance-tree illustration

The BAL logo now sits at the base of the circuit tree (in place of the
generic Bitcoin coin), the art fills the card width, and the card's lower
edge lines up with the text column.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

index.html

@@ -99,7 +99,8 @@ section{scroll-margin-top:72px}
 /* ---------- Hero ---------- */
 header.hero{padding:56px 0 40px;border-bottom:1px solid var(--line);background:
   radial-gradient(900px 300px at 80% -40%,var(--accent-soft),transparent 70%);}
-.hero .wrap{display:grid;grid-template-columns:1.4fr .9fr;gap:40px;align-items:center}
+/* stretch (not center) so the card's lower edge lines up with the text column */
+.hero .wrap{display:grid;grid-template-columns:1.4fr .9fr;gap:40px;align-items:stretch}
 .hero .badge{
   display:inline-flex;align-items:center;gap:8px;font-size:12px;font-weight:600;
   color:var(--accent);background:var(--accent-soft);border:1px solid #cfe0fb;
@@ -137,14 +138,21 @@ header.hero{padding:56px 0 40px;border-bottom:1px solid var(--line);background:
 .fiat-bar.latest-post{margin-top:11px}
 .fiat-bar.latest-post .btc{font-size:17px;color:var(--accent)}
 
+/*
+  Flex column so the stats pin to the bottom (margin-top:auto), keeping the
+  card's lower edge level with the text column whatever height the art takes.
+*/
 .hero-card{
   background:var(--panel);border:1px solid var(--line);border-radius:14px;
-  box-shadow:var(--shadow-lg);padding:30px 28px;text-align:center;
+  box-shadow:var(--shadow-lg);padding:28px;text-align:center;
+  display:flex;flex-direction:column;
+}
+.hero-card .hero-art{
+  width:100%;height:auto;margin:0 auto 16px;display:block;border-radius:12px;
 }
-.hero-card img{width:138px;height:138px;margin:0 auto 14px;display:block}
 .hero-card .name{font-family:var(--display);font-weight:600;font-size:18px}
 .hero-card .tag{color:var(--muted);font-size:13px;margin-top:2px}
-.hero-card .stats{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:20px}
+.hero-card .stats{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:auto;padding-top:20px}
 .hero-card .stat{background:var(--bg);border:1px solid var(--line);border-radius:10px;padding:12px 8px}
 .hero-card .stat .n{font-family:var(--display);font-weight:600;font-size:20px;line-height:1}
 .hero-card .stat .l{font-size:10px;letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin-top:6px}
@@ -531,7 +539,8 @@ footer .built{font-size:13px;color:var(--muted);margin-top:8px}
     </div>
 
     <aside class="hero-card">
-      <img src="/pitura/logo/Logo_nero.svg" alt="Bitcoin After Life Protocol logo" width="138" height="138">
+      <img class="hero-art" src="/pitura/bal-hero-tree.webp" width="981" height="688"
+           alt="A tree of circuit branches growing from the Bitcoin After Life logo, with padlocks and an envelope at its tips and a clock behind it">
       <div class="name">BAL Protocol</div>
       <div class="tag">Electrum plugin + Will-Executor</div>
       <div class="stats">