.qd-red-arrow {
    display:inline-block;
    color:red;
    font-size:24px;
    animation: arrow-slide 1s infinite;
}
@keyframes arrow-slide {
    0% { transform: translateX(0); opacity: 1; }
    50% { transform: translateX(5px); opacity: 0.7; }
    100% { transform: translateX(0); opacity: 1; }
}