.tuner-box {
    display: grid;
    grid-template-columns: repeat(6, minmax(90px, 1fr));
    gap: 12px;
    margin-top: 25px;
}

.tuner-string {
    border: 1px solid #d5d5d5;
    border-radius: 12px;
    background: #ffffff;
    padding: 18px 10px;
    cursor: pointer;
    transition: 0.2s ease;
    text-align: center;
}

.tuner-string:hover {
    transform: translateY(-2px);
    border-color: #e53935;
}

.tuner-string.is-playing {
    background: #e53935 !important;
    color: #ffffff !important;
    border-color: #e53935 !important;
    box-shadow: 0 0 0 2px rgba(229, 57, 53, 0.15) !important;
}

.tuner-string.is-playing strong,
.tuner-string.is-playing small,
.tuner-string.is-playing .string-number {
    color: #ffffff !important;
}

.tuner-string strong {
    display: block;
    font-size: 32px;
    margin: 5px 0;
}

.tuner-string small {
    display: block;
    opacity: 0.75;
}

.string-number {
    display: block;
    font-size: 18px;
    font-weight: 700;
    color: #666666;
    opacity: 1;
}

#tuner-status {
    margin-top: 20px;
    text-align: center;
    font-weight: 600;
}

@media (max-width: 700px) {
    .tuner-box {
        grid-template-columns: repeat(3, 1fr);
    }
}