diff --git a/shared/stack-layout.css b/shared/stack-layout.css
index 1a74614..13c6743 100644
--- a/shared/stack-layout.css
+++ b/shared/stack-layout.css
@@ -1,4 +1,3 @@
-/* Overlapping scroll slots — each layer covers the one below via z-index */
 .scroll-section {
   height: var(--stack-slot);
   position: relative;
@@ -10,7 +9,7 @@
 
 .scroll-section--final {
   height: var(--stack-slot-last);
-  min-height: 260px;
+  min-height: 280px;
 }
 
 .stack-stop,
@@ -18,18 +17,3 @@
   height: 2rem;
   margin-bottom: 3rem;
 }
-
-/* Body visible only when card is stuck on the stack — next card covers previous */
-.scroll-section:not(.is-stuck) .body,
-.scroll-section:not(.is-stuck) .layer-inner,
-.scroll-section:not(.is-stuck) .frame-body,
-.scroll-section:not(.is-stuck) .unit-body {
-  visibility: hidden;
-  min-height: 0;
-  height: 0;
-  padding-top: 0;
-  padding-bottom: 0;
-  border: none;
-  box-shadow: none;
-  overflow: hidden;
-}
diff --git a/shared/stack-scroll.js b/shared/stack-scroll.js
index 9defb81..33ede73 100644
--- a/shared/stack-scroll.js
+++ b/shared/stack-scroll.js
@@ -1,32 +1,23 @@
-/** Scroll depth + jump + hide upcoming cards until they cover the stack */
+/** Scroll depth + jump-to-layer for stack variants */
 export function initStackScroll(options = {}) {
   const {
     sectionSelector = '.scroll-section',
     depthEl = document.getElementById('depth'),
     depthPrefix = 'L',
     tabSelector = '[data-goto], .jump',
-    panelSelector = '.folder, .layer, .frame, .unit',
   } = options;
 
   const sections = document.querySelectorAll(sectionSelector);
   if (!sections.length) return;
 
-  const reveal = () => {
-    const v = getComputedStyle(document.documentElement).getPropertyValue('--stack-reveal').trim();
-    return parseFloat(v) || 344;
-  };
-
   const mid = () => window.innerHeight * 0.42;
 
   function updateDepth() {
-    const rLine = reveal();
     let active = 0;
-
     sections.forEach((sec) => {
       const r = sec.getBoundingClientRect();
       if (r.top <= mid() && r.bottom > mid()) active = Number(sec.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) => {
@@ -34,21 +25,6 @@ export function initStackScroll(options = {}) {
       if (n === undefined) return;
       el.classList.toggle('active', Number(n) === active);
     });
-
-    sections.forEach((sec) => {
-      const layer = Number(sec.dataset.layer);
-      const panel = sec.querySelector(panelSelector);
-      if (!panel) return;
-
-      const r = sec.getBoundingClientRect();
-      const pr = panel.getBoundingClientRect();
-      const onStack = Math.abs(pr.top - rLine) < 10;
-      const past = r.bottom <= rLine;
-
-      sec.classList.toggle('is-active', layer === active);
-      sec.classList.toggle('is-stuck', onStack);
-      sec.classList.toggle('is-past', past);
-    });
   }
 
   document.querySelectorAll(tabSelector).forEach((tab) => {
@@ -63,6 +39,5 @@ export function initStackScroll(options = {}) {
   });
 
   window.addEventListener('scroll', updateDepth, { passive: true });
-  window.addEventListener('resize', updateDepth, { passive: true });
   updateDepth();
 }
diff --git a/shared/stack-vars.css b/shared/stack-vars.css
index 91d26ae..0e5439c 100644
--- a/shared/stack-vars.css
+++ b/shared/stack-vars.css
@@ -1,13 +1,12 @@
-/* Shared stack scroll — cards share one sticky line and cover via z-index */
+/* Sticky card stack — enough scroll per layer for cover effect */
 :root {
   --stack-nav: 2.5rem;
   --stack-stick: 3rem;
   --stack-step: 2.75rem;
-  --stack-tab-h: 2rem;
-  --stack-reveal: calc(var(--stack-stick) + var(--stack-step) * 6 + var(--stack-tab-h));
   --stack-slot: 100vh;
-  --stack-slot-last: 50vh;
-  /* Scroll one "deck" height before next card covers */
-  --stack-pull: calc(var(--stack-slot) - var(--stack-reveal));
-  --stack-body-h: calc(100dvh - var(--stack-reveal) - 1.25rem);
+  --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);
 }
diff --git a/stack-folder/folder.css b/stack-folder/folder.css
index 4d7cc66..0552425 100644
--- a/stack-folder/folder.css
+++ b/stack-folder/folder.css
@@ -60,18 +60,14 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
   padding: var(--stack-nav) 1rem 0;
 }
 
-/* All folders stick at same line — higher z-index covers previous card */
+/* Card = tab + body; sticky with stepped top; higher z covers previous */
 .folder {
   position: sticky;
-  top: var(--stack-reveal);
   width: 100%;
 }
 
 .tab {
-  position: absolute;
-  left: 0;
-  bottom: 100%;
-  margin-bottom: 0;
+  position: sticky;
   display: block;
   width: fit-content;
   max-width: calc(100% - 1rem);
@@ -85,8 +81,8 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
   border-radius: 8px 8px 0 0;
   cursor: pointer;
   text-align: left;
+  z-index: 60;
   box-shadow: 0 -2px 8px rgba(0,0,0,0.12);
-  transition: filter 0.15s;
 }
 
 .tab:hover { filter: brightness(1.06); }
@@ -94,32 +90,33 @@ body { font-family: var(--sans); background: #2a2824; color: #1a1814; }
 .body {
   background: #e8e2d4;
   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);
   box-shadow: 0 10px 32px rgba(0,0,0,0.25);
 }
 
-.f0 { z-index: 10; }
-.f0 .tab { margin-left: calc(var(--tab-offset) * 0); bottom: calc(100% + var(--stack-step) * 0); background: #c9a86c; color: #2a2824; }
+.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; }
 
-.f1 { z-index: 11; }
-.f1 .tab { margin-left: calc(var(--tab-offset) * 1); bottom: calc(100% + var(--stack-step) * 1); background: #a8c4d4; color: #1a2830; }
+.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; }
 
-.f2 { z-index: 12; }
-.f2 .tab { margin-left: calc(var(--tab-offset) * 2); bottom: calc(100% + var(--stack-step) * 2); background: #b8d4a8; color: #1a2818; }
+.f2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
+.f2 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 2); margin-left: calc(var(--tab-offset) * 2); background: #b8d4a8; color: #1a2818; }
 
-.f3 { z-index: 13; }
-.f3 .tab { margin-left: calc(var(--tab-offset) * 3); bottom: calc(100% + var(--stack-step) * 3); background: #d4b8c4; color: #2a1820; }
+.f3 { top: calc(var(--stack-stick) + var(--stack-step) * 3); z-index: 13; }
+.f3 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 3); margin-left: calc(var(--tab-offset) * 3); background: #d4b8c4; color: #2a1820; }
 
-.f4 { z-index: 14; }
-.f4 .tab { margin-left: calc(var(--tab-offset) * 4); bottom: calc(100% + var(--stack-step) * 4); background: #d4c8a8; color: #2a2418; }
+.f4 { top: calc(var(--stack-stick) + var(--stack-step) * 4); z-index: 14; }
+.f4 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 4); margin-left: calc(var(--tab-offset) * 4); background: #d4c8a8; color: #2a2418; }
 
-.f5 { z-index: 15; }
-.f5 .tab { margin-left: calc(var(--tab-offset) * 5); bottom: calc(100% + var(--stack-step) * 5); background: #c4c4c4; color: #2a2a2a; }
+.f5 { top: calc(var(--stack-stick) + var(--stack-step) * 5); z-index: 15; }
+.f5 .tab { top: calc(var(--stack-stick) + var(--stack-step) * 5); margin-left: calc(var(--tab-offset) * 5); background: #c4c4c4; color: #2a2a2a; }
 
-.f6 { z-index: 16; }
-.f6 .tab { margin-left: calc(var(--tab-offset) * 6); bottom: calc(100% + var(--stack-step) * 6); background: #2a4a6b; color: #e8e2d4; }
+.f6 { top: calc(var(--stack-stick) + var(--stack-step) * 6); z-index: 16; }
+.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; }
 .body h2 { font-size: 1.25rem; margin-bottom: 0.4rem; }
diff --git a/stack-rack/rack.css b/stack-rack/rack.css
index a5f748e..e886e89 100644
--- a/stack-rack/rack.css
+++ b/stack-rack/rack.css
@@ -38,7 +38,6 @@ body {
 
 .unit {
   position: sticky;
-  top: var(--stack-reveal);
   margin: 0;
   border: 1px solid #2a3448;
   background: #161a22;
@@ -47,16 +46,12 @@ body {
 }
 
 .unit-head {
-  position: absolute;
-  left: 0;
-  right: 0;
-  bottom: calc(100% + var(--stack-step) * var(--layer, 0));
+  position: sticky;
   display: flex; align-items: center; gap: 0.5rem;
   padding: 0.4rem 0.65rem;
   background: #1a2030;
-  border: 1px solid #2a3448;
-  border-bottom: none;
-  border-radius: 2px 2px 0 0;
+  border-bottom: 1px solid #2a3448;
+  z-index: 60;
 }
 
 .unit-head button.jump {
@@ -82,13 +77,26 @@ body {
   background: #161a22;
 }
 
-.u0 { z-index: 10; --layer: 0; }
-.u1 { z-index: 11; --layer: 1; }
-.u2 { z-index: 12; --layer: 2; }
-.u3 { z-index: 13; --layer: 3; }
-.u4 { z-index: 14; --layer: 4; }
-.u5 { z-index: 15; --layer: 5; }
-.u6 { z-index: 16; --layer: 6; }
+.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); }
+
+.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); }
+
+.u2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
+.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 .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 .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 .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 .unit-head { top: calc(var(--stack-stick) + var(--stack-step) * 6); }
 
 .unit-body strong { color: #e5e7eb; display: block; margin-bottom: 0.2rem; }
 .unit-body p { color: #6b7280; font-size: 0.7rem; }
diff --git a/stack-trace/trace.css b/stack-trace/trace.css
index 412946b..c3f5e32 100644
--- a/stack-trace/trace.css
+++ b/stack-trace/trace.css
@@ -28,7 +28,6 @@ body {
 
 .frame {
   position: sticky;
-  top: var(--stack-reveal);
   margin: 0 0.5rem;
   border-left: 3px solid #3a3a44;
   background: #141418;
@@ -36,10 +35,7 @@ body {
 }
 
 .frame-line {
-  position: absolute;
-  left: 0;
-  right: 0;
-  bottom: calc(100% + var(--stack-step) * var(--layer, 0));
+  position: sticky;
   display: block;
   font-size: 0.66rem;
   color: #6b9b6b;
@@ -50,6 +46,7 @@ body {
   width: 100%;
   padding: 0.65rem 0 0.35rem 1rem;
   background: #141418;
+  z-index: 60;
 }
 
 .frame-line:hover { color: #9fdf9f; text-decoration: underline; }
@@ -60,13 +57,26 @@ body {
   background: #141418;
 }
 
-.f0 { z-index: 10; border-color: #c4a574; --layer: 0; }
-.f1 { z-index: 11; --layer: 1; }
-.f2 { z-index: 12; --layer: 2; }
-.f3 { z-index: 13; --layer: 3; }
-.f4 { z-index: 14; border-color: #6b8b9b; --layer: 4; }
-.f5 { z-index: 15; --layer: 5; }
-.f6 { z-index: 16; border-color: #7eb87a; --layer: 6; }
+.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); }
+
+.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); }
+
+.f2 { top: calc(var(--stack-stick) + var(--stack-step) * 2); z-index: 12; }
+.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 .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 .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 .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 .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; }
 .frame-body p { color: #6b6966; font-size: 0.74rem; }
diff --git a/stack/stack.css b/stack/stack.css
index 7bc4ba6..b8b5f5d 100644
--- a/stack/stack.css
+++ b/stack/stack.css
@@ -36,7 +36,6 @@ body {
 
 .layer {
   position: sticky;
-  top: var(--stack-reveal);
   margin: 0;
   border-radius: 8px 8px 6px 6px;
   border: 1px solid rgba(255,255,255,0.08);
@@ -45,10 +44,7 @@ body {
 
 .layer-tab {
   position: absolute;
-  left: 10px;
-  right: 10px;
-  bottom: calc(100% + var(--stack-step) * var(--layer, 0));
-  height: 6px;
+  top: -6px; left: 10px; right: 10px; height: 6px;
   border-radius: 5px 5px 0 0;
   background: inherit;
   filter: brightness(1.12);
@@ -62,13 +58,13 @@ body {
   min-height: var(--stack-body-h);
 }
 
-.layer-0 { background: #1c1c20; z-index: 10; --layer: 0; }
-.layer-1 { background: #24242c; z-index: 11; --layer: 1; }
-.layer-2 { background: #2c2c36; z-index: 12; --layer: 2; }
-.layer-3 { background: #343440; z-index: 13; --layer: 3; }
-.layer-4 { background: #3c3c4a; z-index: 14; --layer: 4; }
-.layer-5 { background: #444454; z-index: 15; --layer: 5; }
-.layer-6 { background: #4c4c5e; z-index: 16; --layer: 6; }
+.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-head {
   display: flex; flex-wrap: wrap; align-items: center; gap: 0.35rem 0.65rem;