diff --git a/src/chat/utils/report_generator.py b/src/chat/utils/report_generator.py
index 3bc974757..e23a1d75e 100644
--- a/src/chat/utils/report_generator.py
+++ b/src/chat/utils/report_generator.py
@@ -2,12 +2,13 @@
 该模块用于生成HTML格式的统计报告。
 """
 
-from datetime import datetime, timedelta
-from typing import Any
 import json
 import os
-from jinja2 import Environment, FileSystemLoader
+from datetime import datetime, timedelta
+from typing import Any
+
 import aiofiles
+from jinja2 import Environment, FileSystemLoader
 
 from .statistic_keys import *  # noqa: F403
 
diff --git a/src/chat/utils/statistic.py b/src/chat/utils/statistic.py
index ea89700c6..5b1ce7826 100644
--- a/src/chat/utils/statistic.py
+++ b/src/chat/utils/statistic.py
@@ -412,9 +412,9 @@ class StatisticOutputTask(AsyncTask):
                 (REQ_CNT_BY_MODEL, "model"),
                 (REQ_CNT_BY_MODULE, "module"),
             ]:
-                time_cost_key = f"time_costs_by_{items}"
-                avg_key = f"avg_time_costs_by_{items}"
-                std_key = f"std_time_costs_by_{items}"
+                time_cost_key = f"TIME_COST_BY_{items.upper()}"
+                avg_key = f"AVG_TIME_COST_BY_{items.upper()}"
+                std_key = f"STD_TIME_COST_BY_{items.upper()}"
 
                 for item_name in period_stats[category_key]:
                     time_costs = period_stats[time_cost_key].get(item_name, [])
diff --git a/src/chat/utils/templates/report.css b/src/chat/utils/templates/report.css
index 05a9c3ceb..2229be785 100644
--- a/src/chat/utils/templates/report.css
+++ b/src/chat/utils/templates/report.css
@@ -3,22 +3,20 @@ body {
     font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
     margin: 0;
     padding: 20px;
-    background-color: #F8F9FA; /* Light grey background */
-    color: #495057; /* Softer text color */
+    background-color: #f0f4f8; /* Light blue-gray background */
+    color: #333; /* Darker text for better contrast */
     line-height: 1.6;
 }
 
 /* Main Container */
 .container {
-    max-width: 1200px;
+    max-width: 95%; /* Make container almost full-width */
     margin: 20px auto;
     background-color: #FFFFFF; /* Pure white background */
     padding: 30px;
-    border-radius: 8px;
-    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
-    border: 1px solid #EAEAEA;
+    border-radius: 12px; /* Slightly more rounded corners */
+    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.07); /* Softer, deeper shadow */
 }
-
 /* Dashboard Layout */
 .dashboard-layout {
     display: flex;
@@ -56,28 +54,28 @@ h1 {
     text-align: center;
     font-size: 2.2em;
     margin-bottom: 20px;
-    color: #4A90E2; /* Main blue for title */
+    color: #2A6CB5; /* A deeper, more professional blue */
 }
 
 h2 {
     font-size: 1.5em;
     margin-top: 40px;
     margin-bottom: 15px;
-    border-bottom: 2px solid #EAEAEA;
+    border-bottom: 2px solid #DDE6ED; /* Lighter border color */
 }
 
 /* Info Banners */
 .info-item {
-    background-color: #E9ECEF;
-    padding: 10px 15px;
-    border-radius: 6px;
+    background-color: #E9F2FA; /* Light blue background */
+    padding: 12px 18px;
+    border-radius: 8px;
     margin-bottom: 20px;
     font-size: 0.95em;
-    border: 1px solid #DEE2E6;
+    border: 1px solid #D1E3F4; /* Light blue border */
 }
 
 .info-item strong {
-    color: #4A90E2;
+    color: #2A6CB5; /* Deeper blue for emphasis */
 }
 
 /* Tabs */
@@ -101,12 +99,13 @@ h2 {
 }
 
 .tabs button:hover {
-    color: #212529;
+    color: #2A6CB5;
+    background-color: #f0f4f8; /* Subtle hover background */
 }
 
 .tabs button.active {
-    color: #4A90E2;
-    border-bottom-color: #4A90E2;
+    color: #2A6CB5; /* Active tab color */
+    border-bottom-color: #2A6CB5; /* Active tab border color */
 }
 
 .tab-content {
@@ -131,7 +130,7 @@ h2 {
     padding: 20px;
     border-radius: 8px;
     text-align: center;
-    border: 1px solid #EAEAEA;
+    border: 1px solid #DDE6ED; /* Lighter border */
     transition: all 0.3s ease;
 }
 
@@ -166,9 +165,8 @@ th, td {
     text-align: left;
     border-bottom: 1px solid #EAEAEA;
 }
-
 th {
-    background-color: #4A90E2;
+    background-color: #4A90E2; /* Main theme blue */
     color: white;
     font-weight: bold;
     font-size: 0.95em;
@@ -177,11 +175,11 @@ th {
 }
 
 tr:nth-child(even) {
-    background-color: #F8F9FA;
+    background-color: #F7FAFC; /* Very light blue for alternate rows */
 }
 
 tr:hover {
-    background-color: #E9ECEF;
+    background-color: #E9F2FA; /* Light blue for hover */
 }
 
 /* Chart Container in Sidebar */
diff --git a/src/chat/utils/templates/report.html b/src/chat/utils/templates/report.html
index 9ac7d2e3e..b70146063 100644
--- a/src/chat/utils/templates/report.html
+++ b/src/chat/utils/templates/report.html
@@ -14,6 +14,10 @@
         <div class="tabs">{{ tab_list }}</div>
         {{ tab_content }}
     </div>
+    <script>
+        const all_chart_data_json_string = `{{ all_chart_data|safe }}`;
+        const static_chart_data_json_string = `{{ static_chart_data|safe }}`;
+    </script>
     <script>{{ report_js }}</script>
 </body>
 </html>
\ No newline at end of file
diff --git a/src/chat/utils/templates/report.js b/src/chat/utils/templates/report.js
index 7f944cb3a..8cec90b56 100644
--- a/src/chat/utils/templates/report.js
+++ b/src/chat/utils/templates/report.js
@@ -11,9 +11,15 @@ function showTab(evt, tabName) {
 }
 
 document.addEventListener('DOMContentLoaded', function () {
-    // This is a placeholder for chart data which will be injected by python.
-    const allChartData = JSON.parse('{{ all_chart_data }}')
-;
+ // Chart data is injected by python via the HTML template.
+    let allChartData = {};
+    try {
+        allChartData = JSON.parse(all_chart_data_json_string);
+    } catch (e) {
+        console.error("Failed to parse all_chart_data:", e);
+        console.error("Problematic all_chart_data string:", all_chart_data_json_string);
+    }
+
     let currentCharts = {};
     const chartConfigs = {
         totalCost: { id: 'totalCostChart', title: '总花费', yAxisLabel: '花费 (¥)', dataKey: 'total_cost_data', fill: true },
@@ -73,8 +79,14 @@ document.addEventListener('DOMContentLoaded', function () {
     }
 
     // Static charts
-    const staticChartData = JSON.parse('{{ static_chart_data }}')
-;
+    let staticChartData = {};
+    try {
+        staticChartData = JSON.parse(static_chart_data_json_string);
+    } catch (e) {
+        console.error("Failed to parse static_chart_data:", e);
+        console.error("Problematic static_chart_data string:", static_chart_data_json_string);
+    }
+
     Object.keys(staticChartData).forEach(period_id => {
         const providerCostData = staticChartData[period_id].provider_cost_data;
         const modelCostData = staticChartData[period_id].model_cost_data;
@@ -82,7 +94,7 @@ document.addEventListener('DOMContentLoaded', function () {
 
         // Provider Cost Pie Chart
         const providerCtx = document.getElementById(`providerCostPieChart_${period_id}`);
-        if (providerCtx && providerCostData && providerCostData.data.length > 0) {
+        if (providerCtx && providerCostData && providerCostData.data && providerCostData.data.length > 0) {
             new Chart(providerCtx, {
                 type: 'pie',
                 data: {
@@ -106,7 +118,7 @@ document.addEventListener('DOMContentLoaded', function () {
 
         // Model Cost Bar Chart
         const modelCtx = document.getElementById(`modelCostBarChart_${period_id}`);
-        if (modelCtx && modelCostData && modelCostData.data.length > 0) {
+        if (modelCtx && modelCostData && modelCostData.data && modelCostData.data.length > 0) {
             new Chart(modelCtx, {
                 type: 'bar',
                 data: {