html,
body {
    margin: 0;
    padding: 0;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
}

::-webkit-scrollbar {
    display: none;
}

#demo {
    position: absolute;
    left:20px;
    top:20px;
    background-color: rgb(77, 228, 130);
    display: flex;
    justify-content: center;
    align-items: center;
    text-decoration: none;
    width: 50px;
    height: 30px;
    color: rgb(252, 252, 252);
    translate: all ease 0.3s;
}

#demo:hover {
    background-color: blue;
    color: white;
    transform: scale(1.05);
}

#setting {
    width: 50px;
    height: 50px;
    position: fixed;
    right: 10px;
    top: 10px;
    transition: all ease 0.5s;

    z-index: 1;
}

#setting:hover {
    cursor: pointer;
    transform: rotate(180deg);
}

#setting:active {
    transform: scale(0.8);
}

iframe {
    width: 100vw;
    height: 100vh;
    border: 0;
    z-index: 0;
}

#sidebar {
    position: absolute;
    top: 0;
    right: -650px;
    width: 650px;
    height: 100vh;
    z-index: 9;
    display: flex;
    flex-direction: column;

    background-color: white;
    padding-top: 50px;

    transition: 0.8s cubic-bezier(1, -2.02, 0.38, 2.05);

}

#mask {
    width: 100vw;
    height: 100vh;
    position: absolute;
    left: 0;
    top: 0;
    z-index: 2;
    background-color: rgba(100, green, blue, 0);
    display: none;
}

#close {
    width: 35px;
    height: 35px;
    display: flex;
    justify-content: center;
    align-items: center;
    position: absolute;
    left: 2px;
    top: 2px;
    font-size: 20px;
    font-weight: bold;
    transition: all ease 0.5s;
}

#close:hover {
    transform: rotate(90deg);
    cursor: pointer;
}

#bg-list {
    width: 100%;
    display: flex;
    flex-wrap: wrap;
    overflow: auto;
    padding-bottom: 150px;
}

.bg {
    width: 300px;
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    margin: 10px 5px;
}

.bg img {
    width: 280px;
    height: 150px;



}