html {
    scroll-behavior: smooth;
}

.header-container {
    position: relative;
}

.header-container img.header-img {
    width: 100%;
    height: auto;
    display: block;
}

        .btn-nav {
            position: absolute;
            bottom: -5%;
            left: 50%;
            transform: translateX(-50%);
            display: flex;
            gap: 0px;
            width: 100%;
            justify-content: center;
            box-sizing: border-box;
        }
        .btn-nav a {
            display: block;
            width: 40%;
            max-width: 260px;
        }
        .btn-nav img {
            width: 100%;
            height: auto;
            display: block;
            cursor: pointer;
        }

        @media (max-width: 820px) {
            .btn-nav a {
                width: 30%;
            }
        }
        @media (max-width: 767px) {
            .btn-nav a {
                width: 32%;
            }
        }


.video-container {
    position: relative;
    height: 0;
    padding-bottom: 55.8%;
}
.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
.exhibition-intro .ch {
    font-size: 1.15em;
    text-align: center;
    margin: 25px 4%;
}
.exhibition-intro .en {
    font-size: 1.15em;
    text-align: center;
    margin: 25px 10%;
}
.exhibition-details-bg {
	background-image: url(images/exhibition-details-bg.jpg);
	background-repeat: repeat-y;
}