.scrollbar {
    position: fixed;
    bottom: 2.8rem;
    left: 4.8rem;
    width: 1rem;
    height: 8rem;
    /* background-color: rgba(255, 255, 255, 0.2); */
    background-color: rgba(255, 255, 255, 0.1);
    z-index: 9999;
    opacity: 0;
    transition: opacity 0.3s ease;
    overflow: hidden;
}

.scrollbar.visible {
    opacity: 1;
}

.scrollbar__thumb {
    width: 100%;
    height: 30px;
    background-color: var(--color-text-w);
    transform: translateY(0);
    will-change: transform;
    transition: transform 0.6s ease-out, opacity 0.6s ease-out, height 0.6s ease-out; /* 전환 속도 증가 */
}