#cf-sticky-btn {
    position: fixed;
    left: 0;
    top: 50%;
    z-index: 999999;
    background-color: #364f59;
    color: #fff;
    font-family: inherit;
    font-weight: 700;
    font-size: 16px;
    letter-spacing: .5px;
    padding: 15px 8px;
    cursor: pointer;
    display: none;
    border-radius: 4px 0px 0px 4px;
    box-shadow: 2px 0 5px rgba(0,0,0,.2);
    writing-mode: vertical-rl;
    transform: translateY(-50%) rotate(180deg);
    text-align: center;
    transition: background-color .2s ease;
}
#cf-sticky-btn:hover {
    background-color: #24353d;
}