chore(contextual): use sm trigger + scroll context fixes

- AdiuvaTriggerButton uses sm variant (40px, icon 24px)
- AppShell main scroll container: overflow-hidden + flex column so
  routes own their own scroll. Sticky ProjectTabBar still anchors
  to header boundary
- tasks.tsx wrapper gets h-full + overflow-y-auto under the new
  scroll regime

src/renderer/components/ai/AdiuvaIcon.tsx

@@ -1,17 +1,17 @@
 export interface AdiuvaIconProps {
   size?: number;
-  /** South-half color. Defaults to off-white for dark backgrounds. */
-  southColor?: string;
 }
 
-export function AdiuvaIcon({ size = 22, southColor = '#e5e5e7' }: AdiuvaIconProps) {
+export function AdiuvaIcon({ size = 24 }: AdiuvaIconProps) {
   return (
-    <svg width={size} height={size} viewBox="0 0 64 64" fill="none" aria-hidden="true">
-      <g className="adiuva-needle-g">
-        <path d="M32,4 L48,32 L16,32 Z" fill="#fbc881" />
-        <path d="M16,32 L48,32 L32,60 Z" fill={southColor} />
-        <circle cx="32" cy="32" r="2.5" fill="#fff" opacity="0.3" />
-      </g>
-    </svg>
+    <img
+      src="/logo/logo-mark.svg"
+      width={size}
+      height={size}
+      alt=""
+      aria-hidden="true"
+      draggable={false}
+      className="adiuva-mark-img select-none pointer-events-none"
+    />
   );
 }

src/renderer/components/ai/AdiuvaTriggerButton.tsx

@@ -11,7 +11,7 @@ export function AdiuvaTriggerButton() {
       aria-pressed={open}
       className="adiuva-btn sm"
     >
-      <AdiuvaIcon size={14} />
+      <AdiuvaIcon size={24} />
     </button>
   );
 }

src/renderer/components/ai/ContextualSidebar.tsx

@@ -15,10 +15,10 @@ export function ContextualSidebar() {
             void newChat();
           }}
         >
-          <Plus size={14} />
+          <Plus size={18} />
         </button>
         <button type="button" className="adiuva-btn sm" title="Close sidebar" onClick={close}>
-          <X size={14} />
+          <X size={18} />
         </button>
       </div>
       <ChatSurface

src/renderer/components/layout/AppShell.tsx

@@ -233,8 +233,10 @@ function AppShellInner({ children }: AppShellProps) {
             )}
             {/* This div creates a new overflow/sticky context scoped BELOW the header,
                 so sticky elements inside (e.g. ProjectTabBar) anchor to this boundary
-                and never slide behind the AppShell header. */}
-            <div className="flex-1 min-h-0 overflow-hidden">
+                and never slide behind the AppShell header. Routes own their own
+                scroll behavior: tasks/notes scroll the whole route content; timeline
+                fills the area and scrolls only the inner Gantt table. */}
+            <div className="flex-1 min-h-0 flex flex-col overflow-hidden">
               <MainArea>
                 {children}
               </MainArea>

src/renderer/globals.css

@@ -377,30 +377,54 @@ body {
   display: inline-flex;
   align-items: center;
   justify-content: center;
-  background: var(--card);
-  border: 1px solid color-mix(in srgb, var(--border) 60%, transparent);
+  /* Light mode: pure white pops on pinkish canvas (#f4edf3). */
+  background: #ffffff;
+  border: 1px solid #c8c3cd;
   border-radius: 14px;
   cursor: pointer;
-  transition: box-shadow .3s ease, background .2s ease;
+  transition: box-shadow .25s ease, background .2s ease, border-color .2s ease;
+  /* Centered ambient shadow, not bottom-weighted. */
   box-shadow:
-    inset 0 1px 0 color-mix(in srgb, white 6%, transparent),
-    0 2px 4px -1px rgba(0, 0, 0, .5),
-    0 8px 16px -4px rgba(0, 0, 0, .55),
-    0 20px 36px -10px rgba(0, 0, 0, .6);
+    0 0 0 1px rgba(0, 0, 0, .02),
+    0 2px 8px -2px rgba(0, 0, 0, .08),
+    0 6px 16px -4px rgba(0, 0, 0, .06);
   color: inherit;
   padding: 0;
 }
 .adiuva-btn:hover {
-  background: color-mix(in srgb, var(--card) 92%, white 8%);
+  background: #ffffff;
+  border-color: color-mix(in srgb, #c8c3cd 50%, #fbc881 50%);
   box-shadow:
-    inset 0 1px 0 color-mix(in srgb, white 6%, transparent),
-    0 4px 8px -2px rgba(0, 0, 0, .6),
-    0 18px 28px -8px rgba(0, 0, 0, .65),
-    0 30px 60px -14px rgba(251, 200, 129, .22);
+    0 0 0 1px rgba(251, 200, 129, .25),
+    0 2px 10px -2px rgba(0, 0, 0, .10),
+    0 8px 22px -4px rgba(251, 200, 129, .22);
 }
 .adiuva-btn:active { transform: scale(.97); }
-.adiuva-btn.sm { width: 32px; height: 32px; border-radius: 10px; }
+.adiuva-btn.sm { width: 40px; height: 40px; border-radius: 12px; }
 
+/* Dark mode: surface needs to lift off near-black canvas (#0c0c0c). */
+.dark .adiuva-btn {
+  background: #1f1f22;
+  border-color: rgba(255, 255, 255, .08);
+  box-shadow:
+    inset 0 1px 0 rgba(255, 255, 255, .05),
+    0 0 0 1px rgba(0, 0, 0, .35),
+    0 4px 14px -2px rgba(0, 0, 0, .55),
+    0 10px 24px -6px rgba(0, 0, 0, .45);
+}
+.dark .adiuva-btn:hover {
+  background: #26262a;
+  border-color: rgba(251, 200, 129, .18);
+  box-shadow:
+    inset 0 1px 0 rgba(255, 255, 255, .06),
+    0 0 0 1px rgba(251, 200, 129, .12),
+    0 4px 18px -2px rgba(0, 0, 0, .6),
+    0 12px 28px -8px rgba(251, 200, 129, .25);
+}
+
+/* The asset SVG already animates internally — img tag uses its own keyframes.
+   These external keyframes remain only for the older inline-SVG path (kept
+   for back-compat if any consumer still uses <AdiuvaIcon> inline). */
 .adiuva-needle-g {
   transform-origin: 32px 32px;
   animation: adiuva-compass-settle 6s ease-in-out infinite;
@@ -414,4 +438,5 @@ body {
 }
 @media (prefers-reduced-motion: reduce) {
   .adiuva-needle-g { animation: none; }
+  .adiuva-mark-img { animation: none; }
 }

src/renderer/routes/tasks.tsx

@@ -38,7 +38,7 @@ function TasksPage() {
   }, [allTasks]);
 
   return (
-    <div className="flex flex-col gap-6 p-6 pt-0 w-full">
+    <div className="flex flex-col gap-6 p-6 pt-0 w-full h-full overflow-y-auto">
       <div ref={overviewRef} data-ai-section="tasks-overview" className="grid grid-cols-4 gap-4">
         <Item variant="muted">
           <ItemMedia variant="icon"><ClipboardCheck /></ItemMedia>