diff --git a/shared/stack-layout.css b/shared/stack-layout.css
index 13c6743..e67d41f 100644
--- a/shared/stack-layout.css
+++ b/shared/stack-layout.css
@@ -1,19 +1,6 @@
-.scroll-section {
-  height: var(--stack-slot);
-  position: relative;
-}
-
-.scroll-section + .scroll-section {
-  margin-top: calc(-1 * var(--stack-pull));
-}
-
-.scroll-section--final {
-  height: var(--stack-slot-last);
-  min-height: 280px;
-}
-
+/* Spacer after L6 so scroll can stop */
 .stack-stop,
 .stop {
-  height: 2rem;
-  margin-bottom: 3rem;
+  height: 1px;
+  margin-bottom: 4rem;
 }
diff --git a/shared/stack-scroll.js b/shared/stack-scroll.js
index 33ede73..85dba7d 100644
--- a/shared/stack-scroll.js
+++ b/shared/stack-scroll.js
@@ -1,7 +1,7 @@
-/** Scroll depth + jump-to-layer for stack variants */
+/** Scroll depth + jump — panels are [data-layer] sticky cards */
 export function initStackScroll(options = {}) {
   const {
-    sectionSelector = '.scroll-section',
+    sectionSelector = '.layer[data-layer], .folder[data-layer], .frame[data-layer], .unit[data-layer]',
     depthEl = document.getElementById('depth'),
     depthPrefix = 'L',
     tabSelector = '[data-goto], .jump',
@@ -10,30 +10,30 @@ export function initStackScroll(options = {}) {
   const sections = document.querySelectorAll(sectionSelector);
   if (!sections.length) return;
 
-  const mid = () => window.innerHeight * 0.42;
+  const mid = () => window.innerHeight * 0.45;
 
   function updateDepth() {
     let active = 0;
-    sections.forEach((sec) => {
-      const r = sec.getBoundingClientRect();
-      if (r.top <= mid() && r.bottom > mid()) active = Number(sec.dataset.layer);
+    sections.forEach((el) => {
+      const r = el.getBoundingClientRect();
+      if (r.top <= mid() && r.bottom > mid()) active = Number(el.dataset.layer);
     });
     if (depthEl) depthEl.textContent = `${depthPrefix}${active}`;
 
-    document.querySelectorAll('.stack-ruler button, .stack-ruler [data-goto], .tab-rail button, .tab[data-goto]').forEach((el) => {
-      const n = el.dataset.layer ?? el.dataset.goto;
+    document.querySelectorAll('.stack-ruler button, .stack-ruler [data-goto], .tab-rail button, .tab[data-goto]').forEach((tab) => {
+      const n = tab.dataset.layer ?? tab.dataset.goto;
       if (n === undefined) return;
-      el.classList.toggle('active', Number(n) === active);
+      tab.classList.toggle('active', Number(n) === active);
     });
   }
 
   document.querySelectorAll(tabSelector).forEach((tab) => {
     tab.addEventListener('click', (e) => {
       e.preventDefault();
-      const layer = tab.dataset.goto;
+      const layer = tab.dataset.goto ?? tab.dataset.layer;
       const target = document.querySelector(`${sectionSelector}[data-layer="${layer}"]`);
       if (!target) return;
-      const y = target.getBoundingClientRect().top + window.scrollY - 48;
+      const y = target.getBoundingClientRect().top + window.scrollY - 56;
       window.scrollTo({ top: Math.max(0, y), behavior: 'smooth' });
     });
   });
diff --git a/shared/stack-vars.css b/shared/stack-vars.css
index 0e5439c..ea6bb6e 100644
--- a/shared/stack-vars.css
+++ b/shared/stack-vars.css
@@ -1,12 +1,7 @@
-/* Sticky card stack — enough scroll per layer for cover effect */
+/* Original working sticky stack (cfca7aa) */
 :root {
   --stack-nav: 2.5rem;
-  --stack-stick: 3rem;
+  --stack-stick: 3.5rem;
   --stack-step: 2.75rem;
-  --stack-slot: 100vh;
-  --stack-slot-last: 55vh;
-  /* ~70vh scroll per layer before the next card slides over */
-  --stack-scroll-step: 70vh;
-  --stack-pull: calc(var(--stack-slot) - var(--stack-scroll-step));
-  --stack-body-h: calc(100dvh - var(--stack-stick) - var(--stack-step) * 6 - 3rem);
+  --stack-card-min: 52vh;
 }
diff --git a/stack-folder/folder.css b/stack-folder/folder.css
index 0552425..39d3ff6 100644
--- a/stack-folder/folder.css
+++ b/stack-folder/folder.css
@@ -49,10 +49,7 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
 }
 
 .rail-tab:hover,
-.rail-tab.active {
-  background: #c9a86c;
-  color: #2a2824;
-}
+.rail-tab.active { background: #c9a86c; color: #2a2824; }
 
 .mount {
   width: min(640px, 100%);
@@ -60,9 +57,11 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
   padding: var(--stack-nav) 1rem 0;
 }
 
-/* Card = tab + body; sticky with stepped top; higher z covers previous */
+/* Same pattern as /stack/ — one sticky card, next covers previous */
 .folder {
   position: sticky;
+  min-height: var(--stack-card-min);
+  margin-bottom: 1.25rem;
   width: 100%;
 }
 
@@ -81,7 +80,7 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
   border-radius: 8px 8px 0 0;
   cursor: pointer;
   text-align: left;
-  z-index: 60;
+  z-index: 80;
   box-shadow: 0 -2px 8px rgba(0,0,0,0.12);
 }
 
@@ -92,30 +91,29 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
   border: 1px solid #c4b8a8;
   border-top: none;
   border-radius: 0 10px 10px 10px;
-  padding: 1.25rem 1.4rem 2rem;
-  min-height: var(--stack-body-h);
+  padding: 1.25rem 1.4rem 1.5rem;
   box-shadow: 0 10px 32px rgba(0,0,0,0.25);
 }
 
-.f0 { top: calc(var(--stack-stick) + var(--stack-step) * 0); z-index: 10; }
-.f0 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 0); margin-left: calc(var(--tab-offset) * 0); background: #c9a86c; color: #2a2824; }
+.f0 { top: var(--stack-stick); z-index: 1; }
+.f0 .tab { top: var(--stack-stick); margin-left: calc(var(--tab-offset) * 0); background: #c9a86c; color: #2a2824; }
 
-.f1 { top: calc(var(--stack-stick) + var(--stack-step) * 1); z-index: 11; }
-.f1 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 1); margin-left: calc(var(--tab-offset) * 1); background: #a8c4d4; color: #1a2830; }
+.f1 { top: calc(var(--stack-stick) + var(--stack-step)); z-index: 2; }
+.f1 .tab { top: calc(var(--stack-stick) + var(--stack-step)); margin-left: calc(var(--tab-offset) * 1); background: #a8c4d4; color: #1a2830; }
 
-.f2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
+.f2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 3; }
 .f2 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 2); margin-left: calc(var(--tab-offset) * 2); background: #b8d4a8; color: #1a2818; }
 
-.f3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 13; }
+.f3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 4; }
 .f3 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 3); margin-left: calc(var(--tab-offset) * 3); background: #d4b8c4; color: #2a1820; }
 
-.f4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 14; }
+.f4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 5; }
 .f4 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 4); margin-left: calc(var(--tab-offset) * 4); background: #d4c8a8; color: #2a2418; }
 
-.f5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 15; }
+.f5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 6; }
 .f5 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 5); margin-left: calc(var(--tab-offset) * 5); background: #c4c4c4; color: #2a2a2a; }
 
-.f6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 16; }
+.f6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 7; margin-bottom: 4rem; }
 .f6 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 6); margin-left: calc(var(--tab-offset) * 6); background: #2a4a6b; color: #e8e2d4; }
 
 .body h1 { font-size: 1.65rem; margin-bottom: 0.35rem; }
@@ -139,7 +137,7 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
 
 @media (max-width: 720px) {
   .tab-rail { display: none; }
-  :root { --tab-offset: 1.4rem; --stack-step: 2.25rem; }
+  :root { --stack-step: 1.75rem; --tab-offset: 1.4rem; --stack-card-min: 48vh; }
   .f5 .tab { margin-left: calc(var(--tab-offset) * 4); }
   .f6 .tab { margin-left: calc(var(--tab-offset) * 3); }
 }
diff --git a/stack-folder/index.html b/stack-folder/index.html
index b51554c..3fab136 100644
--- a/stack-folder/index.html
+++ b/stack-folder/index.html
@@ -28,71 +28,64 @@
   </div>
 
   <main class="mount">
-    <div class="scroll-section" data-layer="0">
-      <article class="folder f0" id="layer-0">
-        <button type="button" class="tab" data-goto="0">L0 · foundation</button>
-        <div class="body">
-          <h1>Levkin</h1>
-          <p>Software development · Canada · remote</p>
-          <p class="avail">Taking new engagements · 15+ yrs · 8h→2m</p>
-        </div>
-      </article>
-    </div>
-    <div class="scroll-section" data-layer="1">
-      <article class="folder f1" id="layer-1">
-        <button type="button" class="tab" data-goto="1">L1 · application</button>
-        <div class="body">
-          <h2>Custom software</h2>
-          <p>Web apps, APIs, tools — TypeScript · Python · .NET · PostgreSQL</p>
-        </div>
-      </article>
-    </div>
-    <div class="scroll-section" data-layer="2">
-      <article class="folder f2" id="layer-2">
-        <button type="button" class="tab" data-goto="2">L2 · automation</button>
-        <div class="body">
-          <h2>Automation</h2>
-          <p>n8n · Zapier · CI/CD · LLMs · <a href="https://auto.levkin.ca">auto.levkin.ca</a></p>
-        </div>
-      </article>
-    </div>
-    <div class="scroll-section" data-layer="3">
-      <article class="folder f3" id="layer-3">
-        <button type="button" class="tab" data-goto="3">L3 · enterprise</button>
-        <div class="body">
-          <h2>CaseWare &amp; CaseView</h2>
-          <p>15+ years · CaseWare Intl, MNP, JazzIt · <a href="https://caseware.levkin.ca">caseware.levkin.ca</a></p>
-        </div>
-      </article>
-    </div>
-    <div class="scroll-section" data-layer="4">
-      <article class="folder f4" id="layer-4">
-        <button type="button" class="tab" data-goto="4">L4 · quality</button>
-        <div class="body">
-          <h2>Quality engineering</h2>
-          <p>Senior SDET · <a href="https://iliadobkin.com">iliadobkin.com</a></p>
-        </div>
-      </article>
-    </div>
-    <div class="scroll-section" data-layer="5">
-      <article class="folder f5" id="layer-5">
-        <button type="button" class="tab" data-goto="5">L5 · operations</button>
-        <div class="body">
-          <h2>Job Ops</h2>
-          <p>Internal hiring orchestrator · <a href="https://jobs.levkin.ca">jobs.levkin.ca</a></p>
-        </div>
-      </article>
-    </div>
-    <div class="scroll-section scroll-section--final" data-layer="6">
-      <article class="folder f6" id="layer-6">
-        <button type="button" class="tab" data-goto="6">L6 · interface</button>
-        <div class="body">
-          <h2>Engage</h2>
-          <p>Discover → Proposal → Ship → Maintain</p>
-          <p><a class="btn" href="https://cal.levkin.ca/ilia/consult">Book 15 min</a> <a class="btn ghost" href="mailto:hello@levkine.ca">hello@levkine.ca</a></p>
-        </div>
-      </article>
-    </div>
+    <article class="folder f0" data-layer="0" id="layer-0">
+      <button type="button" class="tab" data-goto="0">L0 · foundation</button>
+      <div class="body">
+        <h1>Levkin</h1>
+        <p>Software development · Canada · remote</p>
+        <p class="avail">Taking new engagements · 15+ yrs · 8h→2m</p>
+      </div>
+    </article>
+
+    <article class="folder f1" data-layer="1" id="layer-1">
+      <button type="button" class="tab" data-goto="1">L1 · application</button>
+      <div class="body">
+        <h2>Custom software</h2>
+        <p>Web apps, APIs, tools — TypeScript · Python · .NET · PostgreSQL</p>
+      </div>
+    </article>
+
+    <article class="folder f2" data-layer="2" id="layer-2">
+      <button type="button" class="tab" data-goto="2">L2 · automation</button>
+      <div class="body">
+        <h2>Automation</h2>
+        <p>n8n · Zapier · CI/CD · LLMs · <a href="https://auto.levkin.ca">auto.levkin.ca</a></p>
+      </div>
+    </article>
+
+    <article class="folder f3" data-layer="3" id="layer-3">
+      <button type="button" class="tab" data-goto="3">L3 · enterprise</button>
+      <div class="body">
+        <h2>CaseWare &amp; CaseView</h2>
+        <p>15+ years · CaseWare Intl, MNP, JazzIt · <a href="https://caseware.levkin.ca">caseware.levkin.ca</a></p>
+      </div>
+    </article>
+
+    <article class="folder f4" data-layer="4" id="layer-4">
+      <button type="button" class="tab" data-goto="4">L4 · quality</button>
+      <div class="body">
+        <h2>Quality engineering</h2>
+        <p>Senior SDET · <a href="https://iliadobkin.com">iliadobkin.com</a></p>
+      </div>
+    </article>
+
+    <article class="folder f5" data-layer="5" id="layer-5">
+      <button type="button" class="tab" data-goto="5">L5 · operations</button>
+      <div class="body">
+        <h2>Job Ops</h2>
+        <p>Internal hiring orchestrator · <a href="https://jobs.levkin.ca">jobs.levkin.ca</a></p>
+      </div>
+    </article>
+
+    <article class="folder f6" data-layer="6" id="layer-6">
+      <button type="button" class="tab" data-goto="6">L6 · interface</button>
+      <div class="body">
+        <h2>Engage</h2>
+        <p>Discover → Proposal → Ship → Maintain</p>
+        <p><a class="btn" href="https://cal.levkin.ca/ilia/consult">Book 15 min</a> <a class="btn ghost" href="mailto:hello@levkine.ca">hello@levkine.ca</a></p>
+      </div>
+    </article>
+
     <div class="stack-stop"></div>
   </main>
 
diff --git a/stack-rack/index.html b/stack-rack/index.html
index dd1cb4d..0f00e9d 100644
--- a/stack-rack/index.html
+++ b/stack-rack/index.html
@@ -13,13 +13,34 @@
   <div class="rack-frame">
     <div class="rack-label">LEV-RACK-01</div>
     <main class="mount">
-      <div class="scroll-section" data-layer="0"><article class="unit u0"><header class="unit-head"><button type="button" class="jump" data-goto="0"><span class="led on"></span><span class="uid">U0</span><span class="svc">foundation</span></button></header><div class="unit-body"><strong>Levkin</strong><p>Software dev · CA · 15+ yrs</p></div></article></div>
-      <div class="scroll-section" data-layer="1"><article class="unit u1"><header class="unit-head"><button type="button" class="jump" data-goto="1"><span class="led on"></span><span class="uid">U1</span><span class="svc">application</span></button></header><div class="unit-body"><strong>custom_software</strong><p>TS · Python · .NET</p></div></article></div>
-      <div class="scroll-section" data-layer="2"><article class="unit u2"><header class="unit-head"><button type="button" class="jump" data-goto="2"><span class="led on"></span><span class="uid">U2</span><span class="svc">automation</span></button><a class="ext" href="https://auto.levkin.ca">auto↗</a></header><div class="unit-body"><strong>pipeline</strong><p>n8n · CI/CD</p></div></article></div>
-      <div class="scroll-section" data-layer="3"><article class="unit u3"><header class="unit-head"><button type="button" class="jump" data-goto="3"><span class="led on"></span><span class="uid">U3</span><span class="svc">enterprise</span></button><a class="ext" href="https://caseware.levkin.ca">case↗</a></header><div class="unit-body"><strong>caseware</strong><p>MNP · JazzIt</p></div></article></div>
-      <div class="scroll-section" data-layer="4"><article class="unit u4"><header class="unit-head"><button type="button" class="jump" data-goto="4"><span class="led blink"></span><span class="uid">U4</span><span class="svc">quality</span></button><a class="ext" href="https://iliadobkin.com">sdet↗</a></header><div class="unit-body"><strong>sdet_suite</strong><p>iliadobkin.com</p></div></article></div>
-      <div class="scroll-section" data-layer="5"><article class="unit u5"><header class="unit-head"><button type="button" class="jump" data-goto="5"><span class="led"></span><span class="uid">U5</span><span class="svc">ops</span></button><a class="ext" href="https://jobs.levkin.ca">jobs↗</a></header><div class="unit-body"><strong>job_ops</strong><p>auth</p></div></article></div>
-      <div class="scroll-section scroll-section--final" data-layer="6"><article class="unit u6"><header class="unit-head"><button type="button" class="jump" data-goto="6"><span class="led on"></span><span class="uid">U6</span><span class="svc">interface</span></button></header><div class="unit-body"><strong>engage()</strong><p><a href="https://cal.levkin.ca/ilia/consult">book</a> · <a href="mailto:hello@levkine.ca">mail</a></p></div></article></div>
+      <article class="unit u0" data-layer="0">
+        <header class="unit-head"><button type="button" class="jump" data-goto="0"><span class="led on"></span><span class="uid">U0</span><span class="svc">foundation</span></button></header>
+        <div class="unit-body"><strong>Levkin</strong><p>Software dev · CA · 15+ yrs</p></div>
+      </article>
+      <article class="unit u1" data-layer="1">
+        <header class="unit-head"><button type="button" class="jump" data-goto="1"><span class="led on"></span><span class="uid">U1</span><span class="svc">application</span></button></header>
+        <div class="unit-body"><strong>custom_software</strong><p>TS · Python · .NET</p></div>
+      </article>
+      <article class="unit u2" data-layer="2">
+        <header class="unit-head"><button type="button" class="jump" data-goto="2"><span class="led on"></span><span class="uid">U2</span><span class="svc">automation</span></button><a class="ext" href="https://auto.levkin.ca">auto↗</a></header>
+        <div class="unit-body"><strong>pipeline</strong><p>n8n · CI/CD</p></div>
+      </article>
+      <article class="unit u3" data-layer="3">
+        <header class="unit-head"><button type="button" class="jump" data-goto="3"><span class="led on"></span><span class="uid">U3</span><span class="svc">enterprise</span></button><a class="ext" href="https://caseware.levkin.ca">case↗</a></header>
+        <div class="unit-body"><strong>caseware</strong><p>MNP · JazzIt</p></div>
+      </article>
+      <article class="unit u4" data-layer="4">
+        <header class="unit-head"><button type="button" class="jump" data-goto="4"><span class="led blink"></span><span class="uid">U4</span><span class="svc">quality</span></button><a class="ext" href="https://iliadobkin.com">sdet↗</a></header>
+        <div class="unit-body"><strong>sdet_suite</strong><p>iliadobkin.com</p></div>
+      </article>
+      <article class="unit u5" data-layer="5">
+        <header class="unit-head"><button type="button" class="jump" data-goto="5"><span class="led"></span><span class="uid">U5</span><span class="svc">ops</span></button><a class="ext" href="https://jobs.levkin.ca">jobs↗</a></header>
+        <div class="unit-body"><strong>job_ops</strong><p>auth</p></div>
+      </article>
+      <article class="unit u6" data-layer="6">
+        <header class="unit-head"><button type="button" class="jump" data-goto="6"><span class="led on"></span><span class="uid">U6</span><span class="svc">interface</span></button></header>
+        <div class="unit-body"><strong>engage()</strong><p><a href="https://cal.levkin.ca/ilia/consult">book</a> · <a href="mailto:hello@levkine.ca">mail</a></p></div>
+      </article>
       <div class="stop"></div>
     </main>
   </div>
diff --git a/stack-rack/rack.css b/stack-rack/rack.css
index e886e89..7d6a083 100644
--- a/stack-rack/rack.css
+++ b/stack-rack/rack.css
@@ -38,7 +38,8 @@ body {
 
 .unit {
   position: sticky;
-  margin: 0;
+  min-height: var(--stack-card-min);
+  margin-bottom: 1.25rem;
   border: 1px solid #2a3448;
   background: #161a22;
   border-radius: 2px;
@@ -51,7 +52,7 @@ body {
   padding: 0.4rem 0.65rem;
   background: #1a2030;
   border-bottom: 1px solid #2a3448;
-  z-index: 60;
+  z-index: 80;
 }
 
 .unit-head button.jump {
@@ -72,30 +73,29 @@ body {
 .unit-head a.ext { color: #60a5fa; text-decoration: none; font-size: 0.58rem; }
 
 .unit-body {
-  padding: 0.6rem 0.7rem 2rem;
-  min-height: var(--stack-body-h);
+  padding: 0.6rem 0.7rem 1.5rem;
   background: #161a22;
 }
 
-.u0 { top: calc(var(--stack-stick) + var(--stack-step) * 0); z-index: 10; }
-.u0 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 0); }
+.u0 { top: var(--stack-stick); z-index: 1; }
+.u0 .unit-head { top: var(--stack-stick); }
 
-.u1 { top: calc(var(--stack-stick) + var(--stack-step) * 1); z-index: 11; }
-.u1 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 1); }
+.u1 { top: calc(var(--stack-stick) + var(--stack-step)); z-index: 2; }
+.u1 .unit-head { top: calc(var(--stack-stick) + var(--stack-step)); }
 
-.u2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
+.u2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 3; }
 .u2 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 2); }
 
-.u3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 13; }
+.u3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 4; }
 .u3 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 3); }
 
-.u4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 14; }
+.u4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 5; }
 .u4 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 4); }
 
-.u5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 15; }
+.u5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 6; }
 .u5 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 5); }
 
-.u6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 16; }
+.u6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 7; margin-bottom: 4rem; }
 .u6 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 6); }
 
 .unit-body strong { color: #e5e7eb; display: block; margin-bottom: 0.2rem; }
diff --git a/stack-trace/index.html b/stack-trace/index.html
index ef3d037..e3240b8 100644
--- a/stack-trace/index.html
+++ b/stack-trace/index.html
@@ -11,13 +11,34 @@
 <body>
   <nav class="nav"><a href="/">← options</a><a href="/stack/">cards</a><a href="/stack-folder/">folder</a><a href="/stack-rack/">rack</a><span id="depth">#0</span></nav>
   <main class="mount">
-    <div class="scroll-section" data-layer="0"><article class="frame f0"><button type="button" class="frame-line" data-goto="0">at Levkin.foundation (levkin.ca:0)</button><div class="frame-body"><strong>Levkin</strong><p>Canadian software practice · 15+ yrs · remote</p></div></article></div>
-    <div class="scroll-section" data-layer="1"><article class="frame f1"><button type="button" class="frame-line" data-goto="1">at Levkin.application (levkin.ca:1)</button><div class="frame-body"><strong>custom_software()</strong><p>TS · Python · .NET · APIs</p></div></article></div>
-    <div class="scroll-section" data-layer="2"><article class="frame f2"><button type="button" class="frame-line" data-goto="2">at Levkin.automation (auto.levkin.ca:2)</button><div class="frame-body"><strong>automation_pipeline()</strong><p>n8n · CI/CD · LLMs</p></div></article></div>
-    <div class="scroll-section" data-layer="3"><article class="frame f3"><button type="button" class="frame-line" data-goto="3">at Levkin.caseware (caseware.levkin.ca:3)</button><div class="frame-body"><strong>enterprise_module()</strong><p>CaseWare · MNP · JazzIt</p></div></article></div>
-    <div class="scroll-section" data-layer="4"><article class="frame f4"><button type="button" class="frame-line" data-goto="4">at Levkin.quality (iliadobkin.com:4)</button><div class="frame-body"><strong>sdet_suite()</strong><p><a href="https://iliadobkin.com">iliadobkin.com</a> — traces · Playwright</p></div></article></div>
-    <div class="scroll-section" data-layer="5"><article class="frame f5"><button type="button" class="frame-line" data-goto="5">at Levkin.operations (jobs.levkin.ca:5)</button><div class="frame-body"><strong>job_ops()</strong><p>internal · auth required</p></div></article></div>
-    <div class="scroll-section scroll-section--final" data-layer="6"><article class="frame f6"><button type="button" class="frame-line" data-goto="6">at Levkin.engage (interface:6)</button><div class="frame-body"><strong>main()</strong><p><a href="https://cal.levkin.ca/ilia/consult">book_consult()</a> · <a href="mailto:hello@levkine.ca">send_mail()</a></p></div></article></div>
+    <article class="frame f0" data-layer="0">
+      <button type="button" class="frame-line" data-goto="0">at Levkin.foundation (levkin.ca:0)</button>
+      <div class="frame-body"><strong>Levkin</strong><p>Canadian software practice · 15+ yrs · remote</p></div>
+    </article>
+    <article class="frame f1" data-layer="1">
+      <button type="button" class="frame-line" data-goto="1">at Levkin.application (levkin.ca:1)</button>
+      <div class="frame-body"><strong>custom_software()</strong><p>TS · Python · .NET · APIs</p></div>
+    </article>
+    <article class="frame f2" data-layer="2">
+      <button type="button" class="frame-line" data-goto="2">at Levkin.automation (auto.levkin.ca:2)</button>
+      <div class="frame-body"><strong>automation_pipeline()</strong><p>n8n · CI/CD · LLMs</p></div>
+    </article>
+    <article class="frame f3" data-layer="3">
+      <button type="button" class="frame-line" data-goto="3">at Levkin.caseware (caseware.levkin.ca:3)</button>
+      <div class="frame-body"><strong>enterprise_module()</strong><p>CaseWare · MNP · JazzIt</p></div>
+    </article>
+    <article class="frame f4" data-layer="4">
+      <button type="button" class="frame-line" data-goto="4">at Levkin.quality (iliadobkin.com:4)</button>
+      <div class="frame-body"><strong>sdet_suite()</strong><p><a href="https://iliadobkin.com">iliadobkin.com</a> — traces · Playwright</p></div>
+    </article>
+    <article class="frame f5" data-layer="5">
+      <button type="button" class="frame-line" data-goto="5">at Levkin.operations (jobs.levkin.ca:5)</button>
+      <div class="frame-body"><strong>job_ops()</strong><p>internal · auth required</p></div>
+    </article>
+    <article class="frame f6" data-layer="6">
+      <button type="button" class="frame-line" data-goto="6">at Levkin.engage (interface:6)</button>
+      <div class="frame-body"><strong>main()</strong><p><a href="https://cal.levkin.ca/ilia/consult">book_consult()</a> · <a href="mailto:hello@levkine.ca">send_mail()</a></p></div>
+    </article>
     <div class="stop"></div>
   </main>
   <footer class="foot"><span>// end of stack</span><a href="https://git.levkin.ca">git.levkin.ca</a></footer>
diff --git a/stack-trace/trace.css b/stack-trace/trace.css
index c3f5e32..25e7f45 100644
--- a/stack-trace/trace.css
+++ b/stack-trace/trace.css
@@ -28,7 +28,8 @@ body {
 
 .frame {
   position: sticky;
-  margin: 0 0.5rem;
+  min-height: var(--stack-card-min);
+  margin: 0 0.5rem 1.25rem;
   border-left: 3px solid #3a3a44;
   background: #141418;
   box-shadow: 0 8px 0 #0a0a0c, 0 14px 28px rgba(0,0,0,0.45);
@@ -46,36 +47,35 @@ body {
   width: 100%;
   padding: 0.65rem 0 0.35rem 1rem;
   background: #141418;
-  z-index: 60;
+  z-index: 80;
 }
 
 .frame-line:hover { color: #9fdf9f; text-decoration: underline; }
 
 .frame-body {
-  padding: 0 0 2rem 1rem;
-  min-height: var(--stack-body-h);
+  padding: 0 0 1.5rem 1rem;
   background: #141418;
 }
 
-.f0 { top: calc(var(--stack-stick) + var(--stack-step) * 0); z-index: 10; border-color: #c4a574; }
-.f0 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 0); }
+.f0 { top: var(--stack-stick); z-index: 1; border-color: #c4a574; }
+.f0 .frame-line { top: var(--stack-stick); }
 
-.f1 { top: calc(var(--stack-stick) + var(--stack-step) * 1); z-index: 11; }
-.f1 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 1); }
+.f1 { top: calc(var(--stack-stick) + var(--stack-step)); z-index: 2; }
+.f1 .frame-line { top: calc(var(--stack-stick) + var(--stack-step)); }
 
-.f2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
+.f2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 3; }
 .f2 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 2); }
 
-.f3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 13; }
+.f3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 4; }
 .f3 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 3); }
 
-.f4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 14; border-color: #6b8b9b; }
+.f4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 5; border-color: #6b8b9b; }
 .f4 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 4); }
 
-.f5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 15; }
+.f5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 6; }
 .f5 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 5); }
 
-.f6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 16; border-color: #7eb87a; }
+.f6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 7; border-color: #7eb87a; margin-bottom: 4rem; }
 .f6 .frame-line { top: calc(var(--stack-stick) + var(--stack-step) * 6); }
 
 .frame-body strong { color: #e8e6e3; font-weight: 500; display: block; margin-bottom: 0.2rem; }
diff --git a/stack/index.html b/stack/index.html
index 9d41c74..8df7548 100644
--- a/stack/index.html
+++ b/stack/index.html
@@ -19,55 +19,69 @@
   </nav>
 
   <main class="stack-mount">
-    <div class="scroll-section" data-layer="0"><section class="layer layer-0"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="0">L0</button><span class="layer-name">foundation</span></header>
-      <h1>Levkin</h1>
-      <p class="tagline">Software · Canada · remote</p>
-      <p class="layer-copy">Boutique engineering — production systems, automation, enterprise.</p>
-      <div class="chips"><span>15+ yrs</span><span>8h→2m</span><span>24/7</span></div>
-      <p class="avail">Taking new engagements</p>
-    </div></section></div>
-
-    <div class="scroll-section" data-layer="1"><section class="layer layer-1"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="1">L1</button><span class="layer-name">application</span></header>
-      <h2>Custom software</h2>
-      <p class="layer-copy">Web apps, APIs, internal tools — TS · Python · .NET</p>
-    </div></section></div>
-
-    <div class="scroll-section" data-layer="2"><section class="layer layer-2"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="2">L2</button><span class="layer-name">automation</span><a href="https://auto.levkin.ca" class="layer-link">auto.levkin.ca ↗</a></header>
-      <h2>Automation</h2>
-      <p class="layer-copy">n8n · Zapier · CI/CD · webhooks · LLMs</p>
-    </div></section></div>
-
-    <div class="scroll-section" data-layer="3"><section class="layer layer-3"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="3">L3</button><span class="layer-name">enterprise</span><a href="https://caseware.levkin.ca" class="layer-link">caseware.levkin.ca ↗</a></header>
-      <h2>CaseWare &amp; CaseView</h2>
-      <p class="layer-copy">15+ years · CaseWare Intl, MNP, JazzIt</p>
-    </div></section></div>
-
-    <div class="scroll-section" data-layer="4"><section class="layer layer-4"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="4">L4</button><span class="layer-name">quality</span><a href="https://iliadobkin.com" class="layer-link">iliadobkin.com ↗</a></header>
-      <h2>Quality engineering</h2>
-      <p class="layer-copy">Senior SDET · test automation · CI/CD · trace-driven QA</p>
-    </div></section></div>
-
-    <div class="scroll-section" data-layer="5"><section class="layer layer-5"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="5">L5</button><span class="layer-name">operations</span><a href="https://jobs.levkin.ca" class="layer-link">jobs.levkin.ca ↗</a></header>
-      <h2>Job Ops</h2>
-      <p class="layer-copy">Internal hiring orchestrator (auth required)</p>
-    </div></section></div>
-
-    <div class="scroll-section scroll-section--final" data-layer="6"><section class="layer layer-6"><div class="layer-tab" aria-hidden="true"></div><div class="layer-inner">
-      <header class="layer-head"><button type="button" class="layer-id" data-goto="6">L6</button><span class="layer-name">interface</span></header>
-      <h2>Engage</h2>
-      <p class="layer-copy">Discover → Proposal → Ship → Maintain</p>
-      <div class="contact-row">
-        <a class="btn" href="https://cal.levkin.ca/ilia/consult">Book 15 min</a>
-        <a class="btn btn-ghost" href="mailto:hello@levkine.ca">hello@levkine.ca</a>
+    <section class="layer layer-0" data-layer="0">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="0">L0</button><span class="layer-name">foundation</span></header>
+        <h1>Levkin</h1>
+        <p class="tagline">Software · Canada · remote</p>
+        <p class="layer-copy">Boutique engineering — production systems, automation, enterprise.</p>
+        <div class="chips"><span>15+ yrs</span><span>8h→2m</span><span>24/7</span></div>
+        <p class="avail">Taking new engagements</p>
       </div>
-      <p class="guarantees">Retries · docs · tests first</p>
-    </div></section></div>
+    </section>
+
+    <section class="layer layer-1" data-layer="1">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="1">L1</button><span class="layer-name">application</span></header>
+        <h2>Custom software</h2>
+        <p class="layer-copy">Web apps, APIs, internal tools — TS · Python · .NET</p>
+      </div>
+    </section>
+
+    <section class="layer layer-2" data-layer="2">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="2">L2</button><span class="layer-name">automation</span><a href="https://auto.levkin.ca" class="layer-link">auto.levkin.ca ↗</a></header>
+        <h2>Automation</h2>
+        <p class="layer-copy">n8n · Zapier · CI/CD · webhooks · LLMs</p>
+      </div>
+    </section>
+
+    <section class="layer layer-3" data-layer="3">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="3">L3</button><span class="layer-name">enterprise</span><a href="https://caseware.levkin.ca" class="layer-link">caseware.levkin.ca ↗</a></header>
+        <h2>CaseWare &amp; CaseView</h2>
+        <p class="layer-copy">15+ years · CaseWare Intl, MNP, JazzIt</p>
+      </div>
+    </section>
+
+    <section class="layer layer-4" data-layer="4">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="4">L4</button><span class="layer-name">quality</span><a href="https://iliadobkin.com" class="layer-link">iliadobkin.com ↗</a></header>
+        <h2>Quality engineering</h2>
+        <p class="layer-copy">Senior SDET · test automation · CI/CD · trace-driven QA</p>
+      </div>
+    </section>
+
+    <section class="layer layer-5" data-layer="5">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="5">L5</button><span class="layer-name">operations</span><a href="https://jobs.levkin.ca" class="layer-link">jobs.levkin.ca ↗</a></header>
+        <h2>Job Ops</h2>
+        <p class="layer-copy">Internal hiring orchestrator (auth required)</p>
+      </div>
+    </section>
+
+    <section class="layer layer-6" data-layer="6">
+      <div class="layer-inner">
+        <header class="layer-head"><button type="button" class="layer-id" data-goto="6">L6</button><span class="layer-name">interface</span></header>
+        <h2>Engage</h2>
+        <p class="layer-copy">Discover → Proposal → Ship → Maintain</p>
+        <div class="contact-row">
+          <a class="btn" href="https://cal.levkin.ca/ilia/consult">Book 15 min</a>
+          <a class="btn btn-ghost" href="mailto:hello@levkine.ca">hello@levkine.ca</a>
+        </div>
+        <p class="guarantees">Retries · docs · tests first</p>
+      </div>
+    </section>
 
     <div class="stack-stop" aria-hidden="true"></div>
   </main>
diff --git a/stack/stack.css b/stack/stack.css
index b8b5f5d..9eb614e 100644
--- a/stack/stack.css
+++ b/stack/stack.css
@@ -8,6 +8,8 @@
 
 * { box-sizing: border-box; margin: 0; padding: 0; }
 
+html { scroll-behavior: smooth; }
+
 body {
   font-family: var(--sans);
   background: #0e0e10;
@@ -16,7 +18,7 @@ body {
 }
 
 .nav {
-  position: fixed; top: 0; left: 0; right: 0; z-index: 200;
+  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
   display: flex; align-items: center; gap: 1rem;
   padding: 0.55rem 1rem; font-family: var(--mono); font-size: 0.62rem;
   background: rgba(14, 14, 16, 0.92); backdrop-filter: blur(8px);
@@ -29,42 +31,30 @@ body {
 .depth { color: #c4a574; font-weight: 600; }
 
 .stack-mount {
-  width: min(560px, 100%);
-  margin: 0 auto;
   padding: var(--stack-nav) 1rem 0;
+  max-width: 560px;
+  margin: 0 auto;
 }
 
+/* Each card sticks; next scrolls over previous */
 .layer {
   position: sticky;
-  margin: 0;
-  border-radius: 8px 8px 6px 6px;
+  min-height: var(--stack-card-min);
+  margin-bottom: 1.25rem;
+  border-radius: 8px;
   border: 1px solid rgba(255,255,255,0.08);
   box-shadow: 0 12px 36px rgba(0,0,0,0.5);
 }
 
-.layer-tab {
-  position: absolute;
-  top: -6px; left: 10px; right: 10px; height: 6px;
-  border-radius: 5px 5px 0 0;
-  background: inherit;
-  filter: brightness(1.12);
-  border: 1px solid rgba(255,255,255,0.07);
-  border-bottom: none;
-  pointer-events: none;
-}
+.layer-0 { top: var(--stack-stick); z-index: 1; background: #1c1c20; }
+.layer-1 { top: calc(var(--stack-stick) + var(--stack-step)); z-index: 2; background: #24242c; }
+.layer-2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 3; background: #2c2c36; }
+.layer-3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 4; background: #343440; }
+.layer-4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 5; background: #3c3c4a; }
+.layer-5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 6; background: #444454; }
+.layer-6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 7; background: #4c4c5e; margin-bottom: 4rem; }
 
-.layer-inner {
-  padding: 1.2rem 1.35rem 2rem;
-  min-height: var(--stack-body-h);
-}
-
-.layer-0 { background: #1c1c20; top: calc(var(--stack-stick) + var(--stack-step) * 0); z-index: 10; }
-.layer-1 { background: #24242c; top: calc(var(--stack-stick) + var(--stack-step) * 1); z-index: 11; }
-.layer-2 { background: #2c2c36; top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
-.layer-3 { background: #343440; top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 13; }
-.layer-4 { background: #3c3c4a; top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 14; }
-.layer-5 { background: #444454; top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 15; }
-.layer-6 { background: #4c4c5e; top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 16; }
+.layer-inner { padding: 1.2rem 1.35rem 1.5rem; }
 
 .layer-head {
   display: flex; flex-wrap: wrap; align-items: center; gap: 0.35rem 0.65rem;
@@ -99,7 +89,7 @@ body {
 .guarantees { font-family: var(--mono); font-size: 0.58rem; color: #5a5854; }
 .site-foot {
   display: flex; justify-content: space-between;
-  width: min(560px, 100%); margin: 0 auto;
+  max-width: 560px; margin: 0 auto;
   padding: 0 1.5rem 2.5rem; font-family: var(--mono); font-size: 0.6rem; color: #4a4844;
 }
 .site-foot a { color: #4a4844; text-decoration: none; }
@@ -114,4 +104,7 @@ body {
 .stack-ruler button:hover,
 .stack-ruler button.active { color: #c4a574; }
 
-@media (max-width: 700px) { .variants { display: none; } }
+@media (max-width: 700px) {
+  :root { --stack-step: 1.75rem; --stack-card-min: 48vh; }
+  .variants { display: none; }
+}