diff --git a/templates/reports.html b/templates/reports.html
index 7c683b1..6d60350 100644
--- a/templates/reports.html
+++ b/templates/reports.html
@@ -24,9 +24,9 @@
             box-sizing: border-box;
         }
         .chart-container.large-chart canvas {
-            max-width: 100%;
-            height: 370px !important;
-            width: 100% !important;
+            display: block;
+            margin: 0 auto;
+            /* Remove forced width: 100% to preserve aspect ratio */
         }
         h2 { color: #948979; font-size: 1.1em; margin-bottom: 0.5em; }
         a, button { color: #222831; background: #948979; border: none; padding: 0.7em 1.5em; border-radius: 4px; font-weight: bold; font-size: 1em; transition: background 0.2s; cursor: pointer; text-decoration: none; }