body{
    background-image: url("../images/bgimage.jpg");
    background-size: cover;
}

/* for animation of an element */

.error {
    position: relative;
    animation: shake .1s linear;
    animation-iteration-count: 3;
}

@keyframes shake {
    0% { left: -5px; }
    100% { right: -5px; }
}