body.open_popup {
    overflow: hidden;
}

.bg_onetime_popup {
    position: fixed;
    top: 0px;
    left: 0px;
    z-index: 9999;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    transition: 0.5s;
}

body.open_popup .bg_onetime_popup {
    opacity: 1;
    visibility: visible;
}

.onetime_popup {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
    width: 50%;
    min-width: 500px;
    background-color: #fff;
}

.onetime_popup_title {
    position: relative;
    padding: 1em 80px;
    margin: 0px;
    background-color: #3388dd;
    color: #fff;
    font-size: 32px;
    text-align: center;
    line-height: 1.5;
}

.onetime_popup_title_close {
    position: absolute;
    top: 4%;
    right: 30px;
    width: 30px;
    height: 30px;
    transform: translateY(-50%);
    cursor: pointer;
}
.onetime_popup_title_close::before,
.onetime_popup_title_close::after {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateX(-50%) translateY(-50%);
    width: 100%;
    height: 4px;
    background-color: rgba(0, 0, 0, 0.8);
    content: "";
}
.onetime_popup_title_close::before {
    transform: translateX(-50%) translateY(-50%) rotate(45deg);
}
.onetime_popup_title_close::after {
    transform: translateX(-50%) translateY(-50%) rotate(-45deg);
}

.onetime_popup_content {
    padding: 60px 30px;
    text-align: center;
}