feat: 로또 백테스트 탭 UI 폴리시 (1·2등 컬럼·빈 상태·차트 박스 CSS)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/pages/lotto/evolver/WinnerAnalysisCard.jsx

@@ -25,7 +25,7 @@ export default function WinnerAnalysisCard({ analysis }) {
                 이번 당첨조합 분석치
                 <span className="badge">무작위 상위 {pct}</span>
             </h2>
-            <div className="winner-chart">
+            <div className="backtest-winner-chart">
                 <ResponsiveContainer width="100%" height={240}>
                     <RadarChart data={data}>
                         <PolarGrid stroke="rgba(255,255,255,0.12)" />