diff --git a/docs/AGENTS.md b/docs/AGENTS.md
index fa6b2d8135..a578059bc9 100644
--- a/docs/AGENTS.md
+++ b/docs/AGENTS.md
@@ -20,8 +20,9 @@ These rules are persistent and apply to every documentation session:
 - A page should answer a real question or help complete a real task.
 - Keep ordinary top-level groups inside each tab, with no nested `root`, `directory`, `expanded`, or drilldown behavior.
 - Match the deployed main docs' sidebar rhythm: 14px medium group headings, square links, no horizontal group dividers, and a segmented vertical rail whose active segment follows the current page. Groups remain open and non-collapsible.
+- Keep the Aspen sidebar aligned to the 56px header and disable its early scroll-fade mask.
 - Keep Mintlify's right-side **On this page** behavior and styling unchanged.
-- Keep Aspen's desktop header on one row: logo, tabs, search, actions, and theme toggle.
+- Keep Aspen's desktop header on one row: logo, tabs, search, compact GitHub link with its star count, Playground action, and theme toggle.
 - Record important findings, uncertainties, and decisions in `../research/docs-refactor/NOTES.md`.
 - Update progress and changed decisions in `../research/docs-refactor/PLAN.md`.
 
diff --git a/docs/custom.css b/docs/custom.css
index ad7a2f784d..8fe6a7fec8 100644
--- a/docs/custom.css
+++ b/docs/custom.css
@@ -57,8 +57,10 @@
   --hf-text-tertiary: #999999;
   --hf-heading: #0a0a0a;
   --hf-code-bg: #ffffff;
+  --hf-ui-border: #eeeeee;
   --hf-sidebar-rail: #eeeeee;
   --hf-sidebar-text: #707070;
+  --mintlify-slot-header-height: 3.5rem;
 
   --hf-accent-green: #1a7a0a;
   --hf-accent-green-light: rgba(26, 122, 10, 0.07);
@@ -87,6 +89,7 @@
   --hf-text-tertiary: #666666;
   --hf-heading: #f5f5f5;
   --hf-code-bg: #141414;
+  --hf-ui-border: #2a2a2a;
   --hf-sidebar-rail: #2a2a2a;
   --hf-sidebar-text: #a0a0a0;
 
@@ -165,8 +168,8 @@ a:not([class]):hover {
 
   #navbar > div:has(.nav-tabs) {
     display: grid;
-    grid-template-columns: max-content max-content minmax(12rem, 1fr) max-content;
-    column-gap: 1.25rem;
+    grid-template-columns: max-content max-content minmax(10.25rem, 1fr) max-content;
+    column-gap: 1rem;
     align-items: center;
     height: 3.5rem;
   }
@@ -205,19 +208,31 @@ a:not([class]):hover {
     grid-row: 1;
   }
 
-  /* The repository remains available as a familiar GitHub icon. */
+  #sidebar-content {
+    top: 3.5rem !important;
+    height: calc(100vh - 3.5rem) !important;
+  }
+
+  /* Keep the repository compact, but retain its useful live star count. */
   #navbar a[title="heygen-com/hyperframes"] {
-    width: 2.25rem;
+    width: auto;
+    min-width: 2.25rem;
     height: 2.25rem;
-    padding: 0;
+    padding: 0 0.75rem;
     justify-content: center;
   }
 
-  #navbar a[title="heygen-com/hyperframes"] > span {
+  #navbar a[title="heygen-com/hyperframes"] > span.truncate {
     display: none;
   }
 }
 
+/* Use main's quieter structural border color across Aspen surfaces. */
+#body-content [class*="border-gray-200"],
+#body-content [class*="border-gray-100"] {
+  border-color: var(--hf-ui-border) !important;
+}
+
 /*
  * Match the navigation rhythm and active-page rail used on the main docs.
  * Each link owns one rail segment, so the current page can highlight only
@@ -278,6 +293,17 @@ a:not([class]):hover {
   display: none;
 }
 
+/*
+ * Aspen assumes a 96px header and fades scrolled navigation before it reaches
+ * that boundary. Our header is 56px; align the sticky sidebar to it and let
+ * links clip exactly at the header instead of disappearing early.
+ */
+#navigation-items,
+#navigation-items [data-id] {
+  -webkit-mask-image: none !important;
+  mask-image: none !important;
+}
+
 /* Catalog texture examples */
 
 .hf-texture-preview-panel {
diff --git a/research/docs-refactor/NOTES.md b/research/docs-refactor/NOTES.md
index c9904e166b..b8faa4ff62 100644
--- a/research/docs-refactor/NOTES.md
+++ b/research/docs-refactor/NOTES.md
@@ -203,6 +203,9 @@ New navigation should be task-shaped:
 - Matched the deployed main docs' sidebar treatment: 14px medium group headings, square links, no horizontal dividers, and one border segment per page so the active segment tracks the current page. Groups remain open and non-collapsible.
 - Kept Mintlify's right-side **On this page** surface completely unchanged.
 - Fit the Aspen desktop header into one row, with the GitHub destination shown as a compact icon.
+- Corrected Aspen's stale 96px sticky-sidebar offset to the actual 56px header height and removed its early scroll-fade mask.
+- Restored the GitHub star count while keeping the repository name hidden, and normalized Aspen's darker surface borders to main's quieter border color.
+- Verified that the documentation font did not change: both main and the refactor use the same TT Norms Pro files and the same body and heading typography.
 
 ## Maintenance issue
 
diff --git a/research/docs-refactor/PLAN.md b/research/docs-refactor/PLAN.md
index fce5c53847..3bd921e787 100644
--- a/research/docs-refactor/PLAN.md
+++ b/research/docs-refactor/PLAN.md
@@ -42,6 +42,7 @@ Global header:
 - Keep Aspen’s full-width top navigation. Use the small desktop-only layout override needed to fit the logo, tabs, search, actions, and theme toggle on one row.
 - Keep every left-sidebar group open and non-collapsible. Match the deployed main docs' spacing, group-heading scale, square link treatment, and segmented active-page rail.
 - Keep Mintlify’s default right-side **On this page** behavior and styling.
+- Align Aspen's sticky sidebar to the actual 56px header, remove its premature scroll fade, keep the GitHub star count, and use main's quieter structural border color.
 
 Navigation behavior: