.subscribe-button {
    position: fixed;
    right: clamp(1rem, 2vw, 1.875rem);
    bottom: clamp(1rem, 2vw, 1.875rem);
    z-index: 1040;
}

.subscribe-button > .button {
    display: inline-flex;
    width: 4rem;
    height: 4rem;
    align-items: center;
    justify-content: center;
    border: 1px solid rgba(255, 255, 255, .72);
    border-radius: 50%;
    color: #25d366;
    background: #fff;
    box-shadow: 0 .5rem 1.5rem rgba(0, 0, 0, .22);
    text-decoration: none;
    transition: transform .2s ease, box-shadow .2s ease;
}

.subscribe-button > .button:hover,
.subscribe-button > .button:focus-visible {
    transform: translateY(-3px);
    box-shadow: 0 .75rem 1.75rem rgba(0, 0, 0, .28);
}

.subscribe-button > .button:focus-visible {
    outline: 3px solid rgba(37, 211, 102, .4);
    outline-offset: 3px;
}

@media (max-width: 575.98px) {
    .subscribe-button > .button {
        width: 3.5rem;
        height: 3.5rem;
    }

    .subscribe-button > .button i {
        font-size: 2.25rem;
    }
}