.top_of_the_page {
    position: absolute;
    top: 0;
}
.back_to_top {
    position: fixed;
    bottom: 2em;
    right: 2em;
    z-index: 100;
}
.back_to_top {
    width: 40px;
    height: 40px;
}
.back_to_top {
    background-color: var(--color__1);
    border: 1px solid var(--color__2);
    border-radius: 50%;
    box-shadow: 0 0 10px #00000080;
}
.back_to_top {
    display: flex;
    align-items: center;
    justify-content: center;
}
.back_to_top {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(20px) scale(.85);
}
.back_to_top svg {
    width: auto;
    height: 60%;
}
.back_to_top svg {
    color: #fff;
}

@keyframes backtopIn {
    0% {
        opacity: 0;
        transform: translateY(24px) scale(.75) rotate(-12deg);
        filter: blur(4px);
    }

    60% {
        opacity: 1;
        transform: translateY(-4px) scale(1.08) rotate(4deg);
        filter: blur(0);
    }

    100% {
        opacity: 1;
        transform: translateY(0) scale(1) rotate(0);
        filter: blur(0);
    }
}

@keyframes backtotopOut {
    0% {
        opacity: 1;
        transform: translateY(0) scale(1);
        filter: blur(0);
    }

    100% {
        opacity: 0;
        transform: translateY(18px) scale(.85);
        filter: blur(3px);
    }
}

.back_to_top.BackToTop {
    visibility: visible;
    pointer-events: auto;
}

.back_to_top.backtopIn {
    animation: backtopIn .45s cubic-bezier(.2,.9,.25,1.25) forwards;
}

.back_to_top.backtotopOut {
    animation: backtotopOut .3s ease-in forwards;
}

.back_to_top:hover {
    background-color: #111;
    transform: translateY(-4px) scale(1.08);
    box-shadow:
        0 12px 28px #00000035,
        0 0 0 6px #ffffff10;
    border-color: #ffffff80;
    transition: 
        transform .35s cubic-bezier(.22,1,.36,1),
        box-shadow .35s ease,
        border-color .35s ease;
}

.back_to_top:hover svg {
    transform: translateY(-2px);
    transition: transform .35s cubic-bezier(.22,1,.36,1);
}