.spinner {
    margin: 100px auto;
    width: 50px;
    height: 40px;
    text-align: center;
    font-size: 10px;
    background-color: azure;
    box-shadow: 0 0 10px gray;
    border-radius: 6px;
    z-index: 9999;
}

    .spinner.center {
        position: fixed;
        left: 0;
        right: 0;
        top: 0;
        bottom: 0;
        margin: auto;
    }

    .spinner > div {
        background-color: #333;
        height: 100%;
        width: 6px;
        display: inline-block;
        -webkit-animation: sk-stretchdelay 1.2s infinite ease-in-out;
        animation: sk-stretchdelay 1.2s infinite ease-in-out;
    }

    .spinner .rect2 {
        -webkit-animation-delay: -1.1s;
        animation-delay: -1.1s;
    }

    .spinner .rect3 {
        -webkit-animation-delay: -1.0s;
        animation-delay: -1.0s;
    }

    .spinner .rect4 {
        -webkit-animation-delay: -0.9s;
        animation-delay: -0.9s;
    }

    .spinner .rect5 {
        -webkit-animation-delay: -0.8s;
        animation-delay: -0.8s;
    }

@-webkit-keyframes sk-stretchdelay {
    0%, 40%, 100% {
        -webkit-transform: scaleY(0.4)
    }

    20% {
        -webkit-transform: scaleY(1.0)
    }
}

@keyframes sk-stretchdelay {
    0%, 40%, 100% {
        transform: scaleY(0.4);
        -webkit-transform: scaleY(0.4);
    }

    20% {
        transform: scaleY(1.0);
        -webkit-transform: scaleY(1.0);
    }
}

/* HTML:
    <div class="spinner">
      <div class="rect1"></div>
      <div class="rect2"></div>
      <div class="rect3"></div>
      <div class="rect4"></div>
      <div class="rect5"></div>
    </div>
*/