Hide center label on mobile and enlarge chart

- Hide center label on screens ≤500px (redundant with details box)
- Increase chart height to 95vw (500px) and 98vw (400px)
- Reduce container padding to minimize white space
- Adjust details box margin and max-height calculation

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

styles.css

@@ -350,8 +350,8 @@ body {
         top: 0;
         right: 0;
         width: 100%;
-        margin-top: 20px;
-        max-height: calc(100vh - 90lvw - 140px);
+        margin-top: 15px;
+        max-height: calc(100vh - 90vw - 130px);
         min-width: 100%;
         overflow-y: auto;
     }
@@ -395,23 +395,15 @@ body {
     }
 
     .center-label {
-        text-align: center;
+        display: none;
     }
 
-    .center-month {
-        font-size: 14px;
+    .container {
+        padding: 15px 10px;
     }
 
-    .center-category {
-        font-size: 14px;
-    }
-
-    .center-amount {
-        font-size: 18px;
-    }
-
-    .center-rub {
-        font-size: 16px;
+    .chart-wrapper {
+        height: 95vw;
     }
 }
 
@@ -421,7 +413,7 @@ body {
     }
 
     .container {
-        padding: 15px;
+        padding: 12px 8px;
     }
 
     .month-btn {
@@ -439,20 +431,8 @@ body {
         font-size: 16px;
     }
 
-    .center-month {
-        font-size: 12px;
-    }
-
-    .center-category {
-        font-size: 12px;
-    }
-
-    .center-amount {
-        font-size: 16px;
-    }
-
-    .center-rub {
-        font-size: 14px;
+    .chart-wrapper {
+        height: 98vw;
     }
 
     .details-header {