diff --git a/src/components/usage/TokenBreakdownChart.tsx b/src/components/usage/TokenBreakdownChart.tsx
index 05498ac..7b1084a 100644
--- a/src/components/usage/TokenBreakdownChart.tsx
+++ b/src/components/usage/TokenBreakdownChart.tsx
@@ -1,7 +1,6 @@
 import { useState, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
-import type { ChartData, ChartOptions } from 'chart.js';
-import { Bar } from 'react-chartjs-2';
+import { Line } from 'react-chartjs-2';
 import { Card } from '@/components/ui/Card';
 import { Button } from '@/components/ui/Button';
 import {
@@ -13,21 +12,15 @@ import { buildChartOptions, getHourChartMinWidth } from '@/utils/usage/chartConf
 import type { UsagePayload } from './hooks/useUsageData';
 import styles from '@/pages/UsagePage.module.scss';
 
-const TOKEN_COLORS: Record<TokenCategory, string> = {
-  input: '#8CC21F',
-  output: '#FA6450',
-  cached: '#F5ED58',
-  reasoning: '#00ABA5'
+const TOKEN_COLORS: Record<TokenCategory, { border: string; bg: string }> = {
+  input: { border: '#8b8680', bg: 'rgba(139, 134, 128, 0.25)' },
+  output: { border: '#22c55e', bg: 'rgba(34, 197, 94, 0.25)' },
+  cached: { border: '#f59e0b', bg: 'rgba(245, 158, 11, 0.25)' },
+  reasoning: { border: '#8b5cf6', bg: 'rgba(139, 92, 246, 0.25)' }
 };
 
 const CATEGORIES: TokenCategory[] = ['input', 'output', 'cached', 'reasoning'];
 
-function formatTokens(num: number): string {
-  if (num >= 1e6) return (num / 1e6).toFixed(2) + 'M';
-  if (num >= 1e3) return (num / 1e3).toFixed(2) + 'K';
-  return num.toString();
-}
-
 export interface TokenBreakdownChartProps {
   usage: UsagePayload | null;
   loading: boolean;
@@ -58,94 +51,38 @@ export function TokenBreakdownChart({
       reasoning: t('usage_stats.reasoning_tokens')
     };
 
-    const categoryTotals: Record<TokenCategory, number> = {
-      input: 0,
-      output: 0,
-      cached: 0,
-      reasoning: 0
-    };
-
-    CATEGORIES.forEach((cat) => {
-      categoryTotals[cat] = series.dataByCategory[cat].reduce(
-        (sum, val) => sum + (Number(val) || 0),
-        0,
-      );
-    });
-
-    const data: ChartData<'bar'> = {
+    const data = {
       labels: series.labels,
       datasets: CATEGORIES.map((cat) => ({
         label: categoryLabels[cat],
-        categoryId: cat,
         data: series.dataByCategory[cat],
-        backgroundColor: TOKEN_COLORS[cat],
-        borderColor: isDark ? '#0f172a' : '#ffffff',
-        borderWidth: 1,
-        borderSkipped: false,
-        grouped: false,
-        // Higher order is drawn earlier by Chart.js, so larger series stay behind smaller ones.
-        order: categoryTotals[cat],
-        categoryPercentage: 0.78,
-        barPercentage: 0.82
+        borderColor: TOKEN_COLORS[cat].border,
+        backgroundColor: TOKEN_COLORS[cat].bg,
+        pointBackgroundColor: TOKEN_COLORS[cat].border,
+        pointBorderColor: TOKEN_COLORS[cat].border,
+        fill: true,
+        tension: 0.35
       }))
     };
 
-    const baseOptions = buildChartOptions({ period, labels: series.labels, isDark, isMobile }) as ChartOptions<'bar'>;
-    const options: ChartOptions<'bar'> = {
+    const baseOptions = buildChartOptions({ period, labels: series.labels, isDark, isMobile });
+    const options = {
       ...baseOptions,
       scales: {
         ...baseOptions.scales,
         y: {
           ...baseOptions.scales?.y,
-          stacked: false
+          stacked: true
         },
         x: {
           ...baseOptions.scales?.x,
-          stacked: false
-        }
-      },
-      plugins: {
-        ...baseOptions.plugins,
-        tooltip: {
-          ...baseOptions.plugins?.tooltip,
-          itemSort: (a, b) => a.datasetIndex - b.datasetIndex,
-          callbacks: {
-            ...baseOptions.plugins?.tooltip?.callbacks,
-            // eslint-disable-next-line @typescript-eslint/no-explicit-any
-            label: function (context: any) {
-              const val = Number(context.raw) || 0;
-              const cat = context.dataset.categoryId;
-              let text = `${context.dataset.label}: ${formatTokens(val)}`;
-              
-              if (cat === 'cached') {
-                // eslint-disable-next-line @typescript-eslint/no-explicit-any
-                const inputDs = context.chart.data.datasets.find((ds: any) => ds.categoryId === 'input');
-                const inputVal = inputDs ? (Number(inputDs.data[context.dataIndex]) || 0) : 0;
-                if (inputVal > 0) {
-                  const perc = ((val / inputVal) * 100).toFixed(2);
-                  text += ` (${perc}%)`;
-                }
-              }
-              return text;
-            },
-            // eslint-disable-next-line @typescript-eslint/no-explicit-any
-            footer: function (tooltipItems: any[]) {
-              let total = 0;
-              const dataIndex = tooltipItems[0].dataIndex;
-              // eslint-disable-next-line @typescript-eslint/no-explicit-any
-              tooltipItems[0].chart.data.datasets.forEach((ds: any) => {
-                total += Number(ds.data[dataIndex]) || 0;
-              });
-              return `Total: ${formatTokens(total)}`;
-            }
-          }
+          stacked: true
         }
       }
     };
 
     return { chartData: data, chartOptions: options };
   }, [usage, period, isDark, isMobile, hourWindowHours, t]);
-  const labels = chartData.labels ?? [];
 
   return (
     <Card
@@ -171,7 +108,7 @@ export function TokenBreakdownChart({
     >
       {loading ? (
         <div className={styles.hint}>{t('common.loading')}</div>
-      ) : labels.length > 0 ? (
+      ) : chartData.labels.length > 0 ? (
         <div className={styles.chartWrapper}>
           <div className={styles.chartLegend} aria-label="Chart legend">
             {chartData.datasets.map((dataset, index) => (
@@ -180,7 +117,7 @@ export function TokenBreakdownChart({
                 className={styles.legendItem}
                 title={dataset.label}
               >
-                <span className={styles.legendDot} style={{ backgroundColor: TOKEN_COLORS[CATEGORIES[index]] }} />
+                <span className={styles.legendDot} style={{ backgroundColor: dataset.borderColor }} />
                 <span className={styles.legendLabel}>{dataset.label}</span>
               </div>
             ))}
@@ -191,11 +128,11 @@ export function TokenBreakdownChart({
                 className={styles.chartCanvas}
                 style={
                   period === 'hour'
-                    ? { minWidth: getHourChartMinWidth(labels.length, isMobile) }
+                    ? { minWidth: getHourChartMinWidth(chartData.labels.length, isMobile) }
                     : undefined
                 }
               >
-                <Bar data={chartData} options={chartOptions} />
+                <Line data={chartData} options={chartOptions} />
               </div>
             </div>
           </div>
diff --git a/src/pages/UsagePage.tsx b/src/pages/UsagePage.tsx
index a64bef8..0ee7f79 100644
--- a/src/pages/UsagePage.tsx
+++ b/src/pages/UsagePage.tsx
@@ -2,7 +2,6 @@ import { useState, useMemo, useCallback, useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
   Chart as ChartJS,
-  BarElement,
   CategoryScale,
   LinearScale,
   PointElement,
@@ -47,7 +46,6 @@ import styles from './UsagePage.module.scss';
 
 // Register Chart.js components
 ChartJS.register(
-  BarElement,
   CategoryScale,
   LinearScale,
   PointElement,