.container { max-width: 1200px; margin: 2rem auto; padding: 0 2rem; }
    .header { margin-bottom: 3rem; }
    .header h1 { font-size: 2rem; font-weight: 700; color: #0a66c2; margin-bottom: 0.5rem; }
    .header p { color: #666; font-size: 1rem; }

    .filters { display: flex; gap: 1rem; margin-bottom: 2rem; }
    .filter-btn { padding: 0.5rem 1rem; border: 1px solid #d1d5db; background: white; border-radius: 20px; cursor: pointer; font-weight: 500; color: #666; }
    .filter-btn.active { background: #0a66c2; color: white; border-color: #0a66c2; }

    .leaderboard-table { background: white; border-radius: 8px; box-shadow: 0 1px 3px rgba(0,0,0,0.1); overflow: hidden; }
    .leaderboard-header { display: grid; grid-template-columns: 50px 1fr 150px 150px 150px; gap: 1rem; padding: 1.5rem; background: #f3f5f7; font-weight: 600; color: #0a66c2; border-bottom: 1px solid #e5e7eb; }
    .leaderboard-row { display: grid; grid-template-columns: 50px 1fr 150px 150px 150px; gap: 1rem; padding: 1.5rem; border-bottom: 1px solid #e5e7eb; align-items: center; }
    .leaderboard-row:hover { background: #f9fafb; }

    .rank { text-align: center; font-weight: 700; font-size: 1.2rem; color: #0a66c2; }
    .rank.top1 { font-size: 1.5rem; }
    .rank.top2 { color: #c0c0c0; }
    .rank.top3 { color: #cd7f32; }

    .user-info { display: flex; align-items: center; gap: 1rem; }
    .user-avatar { width: 48px; height: 48px; border-radius: 50%; background: #0a66c2; color: white; display: flex; align-items: center; justify-content: center; font-weight: 700; }
    .user-details h3 { font-weight: 600; color: #0a66c2; margin: 0; }
    .user-details p { color: #666; font-size: 0.9rem; margin: 0.25rem 0 0; }

    .stat { text-align: center; }
    .stat-value { font-weight: 700; color: #0a66c2; font-size: 1.1rem; }
    .stat-label { color: #666; font-size: 0.85rem; margin-top: 0.25rem; }

    .badge { display: inline-block; background: #f3f5f7; padding: 0.25rem 0.75rem; border-radius: 12px; font-size: 0.85rem; color: #0a66c2; font-weight: 500; }

    .tabs { display: flex; gap: 2rem; border-bottom: 1px solid #e5e7eb; margin-bottom: 2rem; }
    .tab { padding-bottom: 1rem; font-weight: 600; color: #666; cursor: pointer; border-bottom: 2px solid transparent; }
    .tab.active { color: #0a66c2; border-bottom-color: #0a66c2; }