body,html {
    height: 100vh;
    box-sizing: border-box;
    display: block;
    position: relative;
    margin: 0;
}

.img-fluid {
    max-width: 100%;
    height: auto;
}
.loader {
    width: 100%;
    height: 100vh;
    overflow: hidden;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-flow: column;
    z-index: 1;
}
.loader>div {
    height: 50%;
    width: 100%;
    position: relative;
}
.loader .img-top {
    z-index: 9;
}
.loader-mobile .img-top-mobile {
     z-index: 9;
}
.loader div img {
    height: 100%;
    width: 100%;
    display: block;
    margin: 0 auto;
}
.loader>div:first-child img {
    object-position: bottom;
}
.loader>div:last-child img {
    object-position: top;
    object-fit: cover;
}

.dien-gia {
    position: absolute;
    bottom:0;
    left:50%;
    transform: translateX(-55%) translateY(35%);
    z-index: 99;
    opacity: 1;
}
#block-1.active .loader .img-top {
    transform: translateY(-100%);
    transition:all 1s ease-in-out;
}
#block-1.active .loader .img-bottom {
    transform: translateY(100%);
    transition:all 1s ease-in-out;
}
.thamgia {
    display: block;
    position: absolute;
    bottom:20px;
    left:50%;
    transform: translateX(-50%);
    height: 20vw;
    width: 20vw;
}

/*** Thư Mời ****/
.thu-moi {
    position: absolute;
    top:0;
    left:0;
    right:0;
    bottom:0;
    width: 100%;
    height: 100%;
    z-index: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    background-image: url(../images/background-content.jpg);
    background-position: 100%;
    background-size: cover;
    background-repeat: no-repeat;
}
.thu-moi>div {
    width: 100%;
    padding:0 10vw;
    transform: scale(.5);
    opacity: 0;
}
.thu-moi>div img {
    -webkit-box-shadow: 14px 18px 23px -6px #000000;
    box-shadow: 14px 18px 23px -6px #000000;
}
#block-1.active .thu-moi>div {
    transform: scale(1);
    transition:all 1s ease-in-out 1s;
    opacity: 1;
}

#block-2 {
    display: none;
}