html, body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    background-color: #000000;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.slideshow-container {
    width: 100vw;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.sponsor-text {
    width: 40%; /* 左側のエリア */
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 5rem;
    font-weight: bold;
    color: #ffffff;
    background-color: #000000;
    text-align: center;
    white-space: nowrap;
}

.slideshow {
    width: 50%; /* 画像のエリア */
    height: 99%;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    position: relative;
}

.slideshow img {
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
    opacity: 0;
    transition: opacity 1.5s ease-in-out;
    position: absolute;
}

.slideshow img.active {
    opacity: 1;
}