.contents-main {
    position: relative;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    min-height: 450px !important;
    max-height: 700px;
}

.contents-main > .centerd {
    display: inline-block;
    position: relative;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    border: none;
    background-color: #fff;
    border-radius: 0.6rem;
}