body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #f4f6f8;
    color: #1f2937;
}

header {
    background: #111827;
    color: white;
    padding: 30px;
    text-align: center;
}

header h1 {
    margin: 0;
    font-size: 32px;
}

header p {
    margin-top: 10px;
    opacity: 0.8;
}

main {
    padding: 30px;
}

.dashboard {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

.card h2 {
    margin-top: 0;
    font-size: 18px;
}

.value {
    font-size: 42px;
    font-weight: bold;
    margin: 15px 0;
}

.status {
    margin-top: 30px;
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

.online {
    display: inline-block;
    margin-top: 10px;
    padding: 8px 18px;
    border-radius: 20px;
    background: #16a34a;
    color: white;
}

@media (max-width: 900px) {
    .dashboard {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .dashboard {
        grid-template-columns: 1fr;
    }
}