#chart-container {
    width: 600px;
    height: 400px;
    max-width: 100%;
    background-color: var(--bg-medium);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.5);
    position: relative;
    z-index: 1;
}

#chart-container::before {
    content: '';
    background-image: url('../img/bk_chart.jpg');
    background-size: cover;
    background-position: center;
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    border-radius: 10px;
    opacity: 0.3;
    z-index: -1;
}

#chart-container h2 {
    text-align: center;
    color: var(--neon-cyan);
    text-shadow: 0 0 8px var(--neon-cyan);
    margin-bottom: 20px;
}

.select-wrapper {
    position: relative;
    display: inline-block;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    border-radius: 6px;
    background-color: #ffffff;
}

#month-select {
    appearance: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-family: 'Segoe UI', Arial, sans-serif;
    color: #333;
    padding: 12px 40px 12px 15px;
    background-color: transparent;
    cursor: pointer;
    outline: none;
    width: 250px;
}

#month-select:focus {
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.25);
}