.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.card {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    padding: 30px;
    text-decoration: none;
    color: inherit;
    transition: all 0.3s;
    text-align: center;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.1);
    border-color: #667eea;
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.card-title {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: #1e293b;
}

.card-description {
    color: #64748b;
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Leaderboard Card - Special Styling */
.card-leaderboard {
    background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
    border: 2px solid #f59e0b;
    position: relative;
    overflow: hidden;
}

.card-leaderboard::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    animation: shine 3s infinite;
}

@keyframes shine {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    50% { transform: translate(10px, 10px) rotate(5deg); }
}

.card-leaderboard .card-title {
    color: white;
    font-weight: 700;
}

.card-leaderboard .card-description {
    color: rgba(255, 255, 255, 0.95);
}

.card-leaderboard:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 12px 30px rgba(251, 191, 36, 0.4);
    border-color: #fbbf24;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.stat-card {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 25px;
    text-align: center;
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 8px;
}

.stat-label {
    color: #64748b;
    font-size: 0.9rem;
}

.chart-container {
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 30px;
    margin-top: 30px;
}

.chart-container h3 {
    margin-bottom: 20px;
    color: #1e293b;
}