diff --git a/src/components/ArchitectureDiagram.css b/src/components/ArchitectureDiagram.css
index eeea10d..366eb85 100644
--- a/src/components/ArchitectureDiagram.css
+++ b/src/components/ArchitectureDiagram.css
@@ -71,19 +71,13 @@
 .node:focus-visible {
   border-color: var(--accent);
 }
-.node-layer {
-  font-family: var(--mono);
-  font-size: 10.5px;
-  letter-spacing: 0.12em;
-  color: var(--accent);
-  text-transform: uppercase;
-}
 .node-title {
   font-family: var(--display);
   font-weight: 600;
   font-size: clamp(14px, 1.5vw, 17px);
   color: #fff;
   line-height: 1.1;
+  white-space: pre-line;
 }
 .node-sub {
   font-family: var(--mono);
@@ -114,7 +108,7 @@
   background: var(--bg-2);
 }
 .node-obs {
-  background: rgba(255, 255, 255, 0.014);
+  background: var(--surface);
   border-style: dashed;
 }
 
diff --git a/src/components/ArchitectureDiagram.jsx b/src/components/ArchitectureDiagram.jsx
index f795d50..a9fec67 100644
--- a/src/components/ArchitectureDiagram.jsx
+++ b/src/components/ArchitectureDiagram.jsx
@@ -41,10 +41,16 @@ function edgePath(e) {
   }
   // node → observability card
   if (e.route === "tap") {
-    const top = byId.obs.y;
+    const o = byId.obs;
+    const top = o.y;
     const [ax, ay] = a.bottom;
-    if (e.from === "reasoner") return `M 555 ${ay} C 467 300 467 452 525 ${top}`;
-    if (e.from === "safety") return `M ${ax} ${ay} C ${ax} 452 702 472 665 ${top}`;
+    // reasoner sits directly above obs with skills between — bow left around the skills box
+    if (e.from === "reasoner") {
+      const bow = byId.skills.x - 33;
+      return `M ${byId.reasoner.x + 55} ${ay} C ${bow} ${ay + 86} ${bow} ${top - 36} ${o.x + 25} ${top}`;
+    }
+    // safety taps in from the right, curving down past obs's right edge
+    if (e.from === "safety") return `M ${ax} ${ay} C ${ax} ${ay + 118} ${o.x + o.w + 12} ${top - 16} ${o.x + o.w - 25} ${top}`;
     return `M ${ax} ${ay} C ${ax} ${ay + 28} ${ax} ${top - 28} ${ax} ${top}`; // skills
   }
   // vertically stacked (same column)
@@ -76,7 +82,7 @@ export default function ArchitectureDiagram() {
           One typed <em>contract</em>, two coupled <em>systems</em>.
         </h2>
         <p className="band-sub">
-          A slow <strong>S2 reasoner</strong> plans in typed tool-calls; a fast <strong>S1 rSkill</strong> layer
+          A slow <strong>reasoner</strong> plans in typed tool-calls; a fast <strong>rSkill</strong> layer
           executes action chunks. Perception lifts detections into spatial memory; both feed the reasoner and the
           rSkills, and a deny-by-default supervisor gates every command before it reaches the robot — whose new
           state flows straight back into perception and the next decision.
@@ -124,7 +130,6 @@ export default function ArchitectureDiagram() {
               onBlur={() => setHovered(null)}
               tabIndex={0}
             >
-              <span className="node-layer">{n.layer}</span>
               <span className="node-title">{n.title}</span>
               <span className="node-sub">{n.sub}</span>
             </div>
diff --git a/src/data/layers.js b/src/data/layers.js
index 1df3c1e..2c841b5 100644
--- a/src/data/layers.js
+++ b/src/data/layers.js
@@ -1,22 +1,25 @@
 // Architecture-diagram nodes + edges — a closed control loop.
-// Coordinates are in the SVG viewBox space (0 0 1120 620).
+// Coordinates are in the SVG viewBox space (0 0 1120 648).
 // Forward flow reads left→right; the loop closes via two feedback paths
 // (robot → world state over the top, robot → sensors along the bottom).
 
 export const NODES = [
-  { id: "sensors", x: 36, y: 230, w: 152, h: 104, group: "io", layer: "L0–L1", title: "Sensors + HAL", sub: "RGB-D · lidar · tactile" },
-  { id: "world", x: 250, y: 118, w: 184, h: 96, group: "io", layer: "L1–L2", title: "World State", sub: "tf2 · 30 Hz · detections" },
-  { id: "memory", x: 250, y: 330, w: 184, h: 96, group: "io", layer: "L2", title: "Spatial Memory", sub: "advisory scene graph" },
-  { id: "reasoner", x: 500, y: 118, w: 190, h: 96, group: "s2", layer: "L4", title: "S2 · Reasoner", sub: "LLM planner · tool-calls" },
-  { id: "skills", x: 500, y: 330, w: 190, h: 96, group: "s1", layer: "L3", title: "S1 · rSkill", sub: "VLA policy · 30–200 Hz" },
-  { id: "safety", x: 756, y: 230, w: 150, h: 104, group: "safety", layer: "L6", title: "Safety", sub: "C++ · deny-by-default" },
-  { id: "robot", x: 968, y: 230, w: 116, h: 104, group: "robot", layer: "act", title: "Robot", sub: "real · sim" },
-  { id: "obs", x: 500, y: 488, w: 190, h: 84, group: "obs", layer: "L7", title: "Observability", sub: "OTel · Foxglove" },
+  { id: "sensors", x: 36, y: 230, w: 120, h: 104, group: "io", title: "Sensors", sub: "RGB-D · lidar · tactile" },
+  { id: "perception", x: 194, y: 118, w: 132, h: 96, group: "io", title: "Perception AI", sub: "detections → spatial" },
+  { id: "world", x: 364, y: 118, w: 132, h: 96, group: "io", title: "World State", sub: "tf2 · 30 Hz · detections" },
+  { id: "memory", x: 364, y: 330, w: 132, h: 96, group: "io", title: "Spatial Memory", sub: "advisory scene graph" },
+  { id: "reasoner", x: 534, y: 118, w: 190, h: 96, group: "s2", title: "Reasoner", sub: "LLM planner · tool-calls" },
+  { id: "skills", x: 534, y: 330, w: 190, h: 96, group: "s1", title: "rSkills\n(robot skills)", sub: "VLA · VLM · reward · ROS" },
+  { id: "safety", x: 762, y: 230, w: 150, h: 104, group: "safety", title: "Safety", sub: "C++ · deny-by-default" },
+  { id: "robot", x: 950, y: 230, w: 134, h: 104, group: "robot", title: "Robot", sub: "Edge · Fleet · Cloud · Sim" },
+  { id: "obs", x: 534, y: 488, w: 190, h: 96, group: "obs", title: "Observability\nTraceability", sub: "OTel · Foxglove" },
 ];
 
 export const EDGES = [
   // forward path
-  { from: "sensors", to: "world" },
+  { from: "sensors", to: "perception" },
+  { from: "perception", to: "world" },
+  { from: "perception", to: "memory" },
   { from: "world", to: "memory" },
   { from: "world", to: "reasoner" },
   { from: "world", to: "skills" },