body {
    margin: 0;
    font-family: Arial, sans-serif;
    color: white;
    text-align: center;
    overflow: visible;
    background-color: #1a1a1a;
}

#background {
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    object-fit: cover;
}

#background::after {
    content: "";
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.3);
    z-index: 1;
}

.overlay {
    position: relative;
    z-index: 2;
    background: rgba(0, 0, 0, 0.4);
    padding: 2rem;
    min-height: 100vh;
}

.controls {
    margin: 1rem 0;
}

button {
    margin: 0.3rem;
    padding: 1rem;
    border: none;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

button:hover {
    background: rgba(255, 255, 255, 0.4);
        outline: 2px solid #ffffff;
    outline-offset: 2px;
}

.lang-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.lang-btn img {
    width: 24px;
    height: 16px;
    object-fit: cover;
    border: 1px solid white;
    border-radius: 2px;
}

.card-number,
table td.number {
    font-variant-numeric: tabular-nums;
    text-shadow: 0 0 4px rgba(0, 0, 0, 0.5);
}

table {
    width: 100%;
    border-collapse: collapse;
}

table th,
table td {
    padding: 0.5rem;
    text-align: center;
    border: 1px solid #4b5563;
}

table td.number {
    word-break: break-word;
    white-space: normal;
}

@media (max-width: 640px) {
    table {
        font-size: 0.75rem;
    }

    table th,
    table td {
        padding: 0.25rem;
    }

    table td.number {
        min-width: 60px;
    }
}

@keyframes flashGreen {
    0% {
        background-color: rgba(34, 197, 94, 0.3);
    }

    100% {
        background-color: transparent;
    }
}

@keyframes flashRed {
    0% {
        background-color: rgba(239, 68, 68, 0.3);
    }

    100% {
        background-color: transparent;
    }
}

.table-flash-green {
    animation: flashGreen 0.8s ease-out;
}

.table-flash-red {
    animation: flashRed 0.8s ease-out;
}