html, body {
    height: 100%;
    margin: 0;    
}
html {
	scroll-behavior: smooth;
}
*{
    font-family:  "Source Sans Pro", Arial,OpenSans, "Hiragino Sans GB", "Microsoft JhengHei", STHeiti, 华文黑体, SimHei, 黑体, sans-serif;
    box-sizing: border-box;
    transition: all 0.3s;
}
body{
    display: flex;
    flex-direction: column;
    flex-wrap: nowrap;
    align-content: center;
    justify-content: flex-start;
    align-items: center;
    background: linear-gradient(to right, rgba(230, 240, 255, 0.96) 0, rgba(255, 255, 255, 0.96) 25%);
}
#container{
    width: 100%;
    max-width: 1600px;
    margin: 0 auto;
    margin-bottom: 120px;
}
header{
    display: flex;
    align-content: center;
    justify-content: flex-start;
    align-items: flex-start;
    flex-wrap: wrap;
    margin-top: 20px;
    margin-bottom: 20px;
}
header>a{
    padding: 10px;
    height: 60px;
    margin: 5px;
    text-align: center;
    color:#337ab7;
    font-weight: bold;
    text-decoration: none;
}
header>a>img{
    height: 100%;
}

header>a.menuitem{
    border-top:8px solid #ddd;
    padding-left: 40px;
    padding-right: 40px;
    padding-top: 5px;
}
header>a.menuitem:hover{
    border-top:8px solid #A8E8FF;
    color:#234767;
}
content{
    position: relative;
    width: 100%;
    display: flex;
    flex-direction: column;
    flex-wrap: nowrap;
    align-content: center;
    justify-content: center;
    align-items: center;
}
content>img{
    width: 100%;
}
/* Programme */
nav{
    display: flex;
    align-content: center;
    justify-content: flex-start;
    align-items: flex-start;
    flex-wrap: nowrap;
}
nav>div.menuitem{
    border-bottom:12px solid #ddd;
    padding-left: 40px;
    padding-right: 40px;
    padding-bottom: 5px;
    margin: 5px;
    font-weight: bold;
    font-family: "Arial Black",sans-serif;
    font-size: 20pt;
    color:#337ab7;
    cursor: pointer;
}
nav>div.menuitem:hover{
    border-bottom:12px solid #A8E8FF;
    color:#234767;
}
.image-container {
    position: relative;
    width: 100%; /* Adjust to your image width */
    overflow: hidden;
}
.image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover; /* Ensures images fill the container */
    transition: transform 0.5s ease-in-out, opacity 0.5s ease-in-out;
    opacity: 0;
    transform: scale(0,1); /* Start off-screen below */
    will-change: transform;
}

.image.active {
    position: relative;
    opacity: 1;
    transform: scale(1,1); /* Visible, in place */
}


video{
    width: 100%;
}
#backtoup{
    position: fixed;
    background-image: url("../images/sidebar.png");
    background-position: right;
    background-size: contain;
    background-repeat: no-repeat;
    width: 120px;
    height: 120px;
    right: -120px;
    bottom: 25%;
    display: flex;
    justify-content: center;
    align-items: center;
}
#backtoup.visible {
    right: 0; /* Visible when scrolling */
}
#backtoup a{
    width: 55%;
    height: 55%;
    position: absolute;
    right: 15px;
}
#backtoup a img{
    width: 100%;
    height: 100%;
}

/* Footer */
footer{
	line-height: 1.5em;
    padding: 25px;
    width: 100%;
    position: relative;
    background-color:  rgb(230,230,230);
    color:rgb(20, 20, 20);
    z-index: 10;
}
footer a{
    color:#444;
    transition: all 0.5s;
}
footer a:hover{
	color:#666;
}
footer img#memberOfVTC{
	position: absolute;
	bottom: 0;
	right: 0;
}

@media (max-width: 1000px){
    header {
        align-items: stretch;
        flex-direction: column;
    }
    #backtoup{
        display: none;
    }
    nav>div.menuitem{
        border-bottom:10px solid #ddd;
        padding-left: 30px;
        padding-right: 30px;
        font-size: 16pt;
    }
    header a.menuitem div{
        font-size: 10pt;
    }
}
@media (max-width: 800px){
    footer{
        line-height: 1.5em;
        font-size: 10pt;
    }

}