.tfb-button {
    position: fixed;
    z-index: 9999;
    background: url('https://cdn-icons-png.flaticon.com/512/2111/2111646.png') no-repeat center center;
    background-size: contain;
    cursor: pointer;
}

/* Position */
.tfb-bottom-right { bottom: 20px; right: 20px; }
.tfb-bottom-left  { bottom: 20px; left: 20px; }
.tfb-top-right    { top: 20px; right: 20px; }
.tfb-top-left     { top: 20px; left: 20px; }

/* Animations */
.tfb-pulse:hover {
    animation: tfbPulse 1.5s infinite;
}
.tfb-bounce:hover {
    animation: tfbBounce 1s;
}
.tfb-shake:hover {
    animation: tfbShake 0.6s;
}
@keyframes tfbPulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}
@keyframes tfbBounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}
@keyframes tfbShake {
    0% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    50% { transform: translateX(5px); }
    75% { transform: translateX(-5px); }
    100% { transform: translateX(0); }
}