#toTopBtn {
    opacity: 0;
    position: fixed;
    bottom: 80px;
    right: 32px; 
    z-index: 999;
    padding: 0;
    border: 2px solid rgba(193, 193, 193, 0.5);
    background-color: rgba(0, 0, 0, 0.2);
    width: 46px;
    height: 46px;
    border-radius: 50px;
    overflow: hidden;
    text-indent: 100px;
    display: flex;
    transition: all 0.5s ease;
    justify-content: center;
}
#toTopBtn:hover{
    background-color: rgba(0, 0, 0, 1);
}
#toTopBtn span{
    display: block;
    width: 16px;
    height: 10px;    
    transition: all 0.5s ease;
    top: 16px;
    position: absolute;   
}
#toTopBtn span::before{
    position: absolute;
    content: "";
    width: 16px;
    height: 10px;
    background-image: url(//www-asia.nissan-cdn.net/content/dam/Nissan/th/BackToTop/arrow-up.svg);
    top: 0;
    left: 0;
}
#toTopBtn span::after{
    position: absolute;
    content: "";
    width: 2px;
    height: 0;
    background-color: #fff;
    transition: all 0.5s ease;
    top: 2px;
    left: 7px;
}
#toTopBtn.up{
    height: 80px;
    align-items: flex-start;
}
#toTopBtn.up span:after{
    height: 40px;
}
@media (max-width: 767px) {
    #toTopBtn {
        width: 36px;
        height: 36px;
    }

    #toTopBtn.up {
        width: 36px;
        height: 62px;
    }
    #toTopBtn span{
        width: 12px;
        height: 8px;
        top: 12px;
    }
    #toTopBtn span::before{
        width: 12px;
        height: 8px;
        background-image: url(//www-asia.nissan-cdn.net/content/dam/Nissan/th/BackToTop/arrow-up_sp.svg);
    }
    #toTopBtn span:after {
        left: 5px;
        width: 1.5px;
    }
    #toTopBtn.up span:after {
        height: 32px;     
    }
}