body {
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
}

.wrapper {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 30px;
}

.grid-container {
    width: 300px;
    aspect-ratio: 4 / 3;
    margin: 30px 10px 0px 10px; /*top,left,bottom,right*/
    padding: 40px;
    background: url('../images/folder_background.jpg') no-repeat center center;
    background-size: cover;
    border-radius: 12px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    box-sizing: border-box;
}

@media (max-width: 500px) {
    .wrapper {
        gap: 5px;
    }

    .grid-container {
        width: 96vw;
        margin: 10px 0px 0px 0px;
        border-radius: 0;
    }
}

.thumbnail-grid {
    margin-top: 20px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: repeat(2, 1fr);
    gap: 5px;
    flex-grow: 1;
}

    .thumbnail-grid img {
        width: 100%;
        height: 100%;
        object-fit: cover;
        border: 2px solid #ccc;
        border-radius: 6px;
        background: white;
        aspect-ratio: 2 / 1;
    }

.grid-container a {
    margin-top: 10px;
    text-align: center;
    font-size: 14px;
    text-decoration: none;
    color: #004080;
    background-color: rgba(255, 255, 255, 0.7);
    padding: 6px;
    border-radius: 6px;
}

    .grid-container a:hover {
        background-color: #ddeeff;
    }