fix: align table headers with row data using CSS grid

- Switch FrustrationTable from flex to grid columns so headers
  and row cells share the same column widths
- Replace bar chart with pie chart for frustration trend
- Remove Card wrapper borders, footer line, and total signals text
- Change dead clicks color from yellow to darker orange

components/behavior/FrustrationTable.tsx

@@ -65,6 +65,9 @@ function SelectorCell({ selector }: { selector: string }) {
   )
 }
 
+const GRID_WITH_AVG = 'grid grid-cols-[1fr_60px_50px_64px_64px_40px] items-center gap-2 h-9 px-2 -mx-2'
+const GRID_NO_AVG = 'grid grid-cols-[1fr_60px_64px_64px_40px] items-center gap-2 h-9 px-2 -mx-2'
+
 function Row({
   item,
   showAvgClicks,
@@ -73,32 +76,30 @@ function Row({
   showAvgClicks?: boolean
 }) {
   return (
-    <div className="flex items-center justify-between h-9 group hover:bg-neutral-50 dark:hover:bg-neutral-800 rounded-lg px-2 -mx-2 transition-colors">
-      <div className="flex items-center gap-3 flex-1 min-w-0">
+    <div className={`${showAvgClicks ? GRID_WITH_AVG : GRID_NO_AVG} group hover:bg-neutral-50 dark:hover:bg-neutral-800 rounded-lg transition-colors`}>
+      <div className="flex items-center gap-2 min-w-0">
         <SelectorCell selector={item.selector} />
         <span
-          className="text-xs text-neutral-400 dark:text-neutral-500 truncate max-w-[120px]"
+          className="text-xs text-neutral-400 dark:text-neutral-500 truncate"
           title={item.page_path}
         >
           {item.page_path}
         </span>
       </div>
-      <div className="flex items-center gap-4 ml-4 shrink-0">
-        {showAvgClicks && item.avg_click_count != null && (
-          <span className="text-xs text-neutral-400 dark:text-neutral-500 tabular-nums">
-            avg {item.avg_click_count.toFixed(1)}
-          </span>
-        )}
-        <span className="text-xs text-neutral-400 dark:text-neutral-500 tabular-nums">
-          {item.sessions} {item.sessions === 1 ? 'session' : 'sessions'}
+      {showAvgClicks && (
+        <span className="text-xs text-neutral-400 dark:text-neutral-500 tabular-nums text-right">
+          {item.avg_click_count != null ? item.avg_click_count.toFixed(1) : '–'}
         </span>
-        <span className="text-xs text-neutral-400 dark:text-neutral-500 tabular-nums" title={item.last_seen}>
-          {formatRelativeTime(item.last_seen)}
-        </span>
-        <span className="text-sm font-semibold text-neutral-600 dark:text-neutral-400 tabular-nums">
-          {formatNumber(item.count)}
-        </span>
-      </div>
+      )}
+      <span className="text-xs text-neutral-400 dark:text-neutral-500 tabular-nums text-right">
+        {item.sessions}
+      </span>
+      <span className="text-xs text-neutral-400 dark:text-neutral-500 tabular-nums text-right" title={item.last_seen}>
+        {formatRelativeTime(item.last_seen)}
+      </span>
+      <span className="text-sm font-semibold text-neutral-600 dark:text-neutral-400 tabular-nums text-right">
+        {formatNumber(item.count)}
+      </span>
     </div>
   )
 }
@@ -166,17 +167,12 @@ export default function FrustrationTable({
           ) : hasData ? (
             <div>
               {/* Column headers */}
-              <div className="flex items-center justify-between px-2 -mx-2 mb-2 text-xs font-medium text-neutral-400 dark:text-neutral-500 uppercase tracking-wider">
-                <div className="flex items-center gap-3">
-                  <span>Selector</span>
-                  <span>Page</span>
-                </div>
-                <div className="flex items-center gap-4">
-                  {showAvgClicks && <span>Avg</span>}
-                  <span>Sessions</span>
-                  <span>Last Seen</span>
-                  <span>Count</span>
-                </div>
+              <div className={`${showAvgClicks ? GRID_WITH_AVG : GRID_NO_AVG} mb-2 text-xs font-medium text-neutral-400 dark:text-neutral-500 uppercase tracking-wider !h-auto`}>
+                <span>Selector / Page</span>
+                {showAvgClicks && <span className="text-right">Avg</span>}
+                <span className="text-right">Sessions</span>
+                <span className="text-right">Last Seen</span>
+                <span className="text-right">Count</span>
               </div>
               <div className="space-y-0.5">
                 {items.map((item, i) => (

components/behavior/FrustrationTrend.tsx

@@ -3,14 +3,6 @@
 import { TrendUp } from '@phosphor-icons/react'
 import { Pie, PieChart } from 'recharts'
 
-import {
-  Card,
-  CardContent,
-  CardDescription,
-  CardFooter,
-  CardHeader,
-  CardTitle,
-} from '@/components/ui/card'
 import {
   ChartContainer,
   ChartTooltip,
@@ -48,7 +40,7 @@ const chartConfig = {
   },
   dead_clicks: {
     label: 'Dead Clicks',
-    color: '#F59E0B',
+    color: '#E04E0A',
   },
   prev_rage_clicks: {
     label: 'Prev Rage Clicks',
@@ -106,12 +98,17 @@ export default function FrustrationTrend({ summary, loading }: FrustrationTrendP
   }
 
   return (
-    <Card className="flex flex-col h-full">
-      <CardHeader className="items-center pb-0">
-        <CardTitle>Frustration Trend</CardTitle>
-        <CardDescription>Current vs. previous period</CardDescription>
-      </CardHeader>
-      <CardContent className="flex-1 pb-0">
+    <div className="bg-white dark:bg-neutral-900 border border-neutral-200 dark:border-neutral-800 rounded-2xl p-6 h-full flex flex-col">
+      <div className="flex items-center justify-between mb-1">
+        <h3 className="text-lg font-semibold text-neutral-900 dark:text-white">
+          Frustration Trend
+        </h3>
+      </div>
+      <p className="text-sm text-neutral-500 dark:text-neutral-400 mb-4">
+        Rage and dead clicks split across current and previous period
+      </p>
+
+      <div className="flex-1">
         <ChartContainer
           config={chartConfig}
           className="mx-auto aspect-square max-h-[250px]"
@@ -129,25 +126,21 @@ export default function FrustrationTrend({ summary, loading }: FrustrationTrendP
             />
           </PieChart>
         </ChartContainer>
-      </CardContent>
-      <CardFooter className="flex-col gap-2 text-sm">
-        <div className="flex items-center gap-2 leading-none font-medium">
-          {totalChange !== null ? (
-            <>
-              {totalChange > 0 ? 'Up' : totalChange < 0 ? 'Down' : 'No change'} by {Math.abs(totalChange)}% vs previous period <TrendUp className="h-4 w-4" />
-            </>
-          ) : totalCurrent > 0 ? (
-            <>
-              {totalCurrent.toLocaleString()} new signals this period <TrendUp className="h-4 w-4" />
-            </>
-          ) : (
-            'No frustration signals detected'
-          )}
-        </div>
-        <div className="leading-none text-muted-foreground">
-          {totalCurrent.toLocaleString()} total signals in current period
-        </div>
-      </CardFooter>
-    </Card>
+      </div>
+
+      <div className="flex items-center justify-center gap-2 text-sm font-medium pt-2">
+        {totalChange !== null ? (
+          <>
+            {totalChange > 0 ? 'Up' : totalChange < 0 ? 'Down' : 'No change'} by {Math.abs(totalChange)}% vs previous period <TrendUp className="h-4 w-4" />
+          </>
+        ) : totalCurrent > 0 ? (
+          <>
+            {totalCurrent.toLocaleString()} new signals this period <TrendUp className="h-4 w-4" />
+          </>
+        ) : (
+          'No frustration signals detected'
+        )}
+      </div>
+    </div>
   )
 }