body {
    text-align: center;
    font-family: 'Arial', sans-serif;
    background-color: #f0f0f0;
    margin: 0;
    padding: 2rem;
}

.btn-container {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 2rem;
}

.box {
    height: 150px;
    width: 150px;
    margin: 2rem;
    border: 8px solid rgba(0, 0, 0, 0.7);
    border-radius: 1.5rem;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease, background-color 0.3s ease;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
    cursor: pointer;
}

.box:hover {
    transform: scale(1.05);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.3);
}

.red {
    background: linear-gradient(135deg, #ff6b6b, #d83e3e);
}

.green {
    background: linear-gradient(135deg, #3bbd3b, #428946);
}

.yellow {
    background: linear-gradient(135deg, #f1e65b, #c1c150);
}

.purple {
    background: linear-gradient(135deg, #9b59b6, #803f80);
}

.flash {
    background: #ffffff;
    border-color: #000000;
}

.userFlash {
    background: #000080;
    border-color: #ffffff;
}

@media (max-width: 600px) {
    .box {
        height: 120px;
        width: 120px;
    }
}