Add CSS styles for DOM optimization and adjust sidebar layout

- Widen sidebar from 340px to 400px for better readability
- Increase player item gap and padding for improved spacing
- Add .grid-content and .buttons-container styles for element pooling

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

static/style.css

@@ -6,7 +6,7 @@
  */
 /* CSS Custom Properties for theme colors and sizing */
 :root {
-  --sidebar-width: 340px;
+  --sidebar-width: 400px;
   --bg-main: #111;
   --bg-side: #1a1a1a;
   --card:    #222;
@@ -441,9 +441,9 @@ body {
     "kills totalkills kph kph kph kph"
     "rares kpr meta meta meta meta"
     "onlinetime deaths tapers tapers tapers tapers";
-  gap: 4px 8px;
+  gap: 6px 12px;
   margin: 6px 0;
-  padding: 8px 10px;
+  padding: 10px 15px;
   background: var(--card);
   border-left: 4px solid transparent;
   transition: none;
@@ -514,6 +514,17 @@ body {
   cursor: pointer;
 }
 
+/* Element pooling optimization containers */
+.grid-content {
+  display: contents; /* Makes container invisible to CSS Grid */
+}
+
+.buttons-container {
+  display: flex;
+  gap: 4px;
+  margin-top: 4px;
+}
+
 .chat-window, .stats-window, .inventory-window {
   position: absolute;
   top: 10px;