.scroll-top-button {
    position: fixed;
    right: max(20px, env(safe-area-inset-right));
    bottom: max(20px, env(safe-area-inset-bottom));
    z-index: 9999;
    width: 50px;
    height: 50px;
    display: grid;
    place-items: center;
    padding: 0 0 4px;
    border: 2px solid #ffffff;
    border-radius: 50%;
    background: #c71920;
    color: #ffffff;
    box-shadow: 0 10px 26px rgba(23, 32, 51, 0.24);
    font: 900 25px/1 Arial, sans-serif;
    cursor: pointer;
    transition: transform 0.2s ease, background-color 0.2s ease, box-shadow 0.2s ease;
}

.scroll-top-button:hover,
.scroll-top-button:focus-visible {
    background: #a82429;
    box-shadow: 0 13px 30px rgba(23, 32, 51, 0.3);
    transform: translateY(-3px);
}

.scroll-top-button:focus-visible {
    outline: 3px solid rgba(199, 25, 32, 0.3);
    outline-offset: 3px;
}

@media (max-width: 600px) {
    .scroll-top-button {
        right: max(14px, env(safe-area-inset-right));
        bottom: max(14px, env(safe-area-inset-bottom));
        width: 46px;
        height: 46px;
        font-size: 22px;
    }
}