jointrashposs/app/spa-loading-template.html

<div id="splash">
    <img id="splashIcon" src="/public/img/icons/icon-128x128.png">
    <div id="splashSpinner"><svg class="spinner bg" viewBox="0 0 152 152" xmlns="http://www.w3.org/2000/svg">
            <g transform="matrix(1,0,0,1,12,12)">
                <circle cx="64" cy="64" r="64" style="fill:none;stroke:currentColor;stroke-width:24px;" />
            </g>
        </svg>
        <svg class="spinner fg" viewBox="0 0 152 152" xmlns="http://www.w3.org/2000/svg">
            <g transform="matrix(1,0,0,1,12,12)">
                <path d="M128,64C128,28.654 99.346,0 64,0C99.346,0 128,28.654 128,64Z" style="fill:none;stroke:currentColor;stroke-width:24px;" />
            </g>
        </svg>
    </div>
</div>

<style>
    #splash {
        background-color: #f9f9f9;
        cursor: wait;
        height: 100vh;
        left: 0;
        opacity: 1;
        position: fixed;
        top: 0;
        transition: opacity .5s ease;
        width: 100vw;
        z-index: 10000
    }

    #splashIcon {
        height: 64px;
        pointer-events: none;
        width: 64px
    }

    #splashIcon,
    #splashSpinner {
        bottom: 0;
        left: 0;
        margin: auto;
        position: absolute;
        right: 0;
        top: 0
    }

    #splashSpinner {
        color: #86b300;
        display: inline-block;
        height: 28px;
        transform: translateY(70px);
        width: 28px
    }

    #splashSpinner>.spinner {
        height: 28px;
        left: 0;
        position: absolute;
        top: 0;
        width: 28px;
        fill-rule: evenodd;
        clip-rule: evenodd;
        stroke-linecap: round;
        stroke-linejoin: round;
        stroke-miterlimit: 1.5
    }

    #splashSpinner>.spinner.bg {
        opacity: .275
    }

    #splashSpinner>.spinner.fg {
        animation: splashSpinner .5s linear infinite
    }

    @keyframes splashSpinner {
        0% {
            transform: rotate(0deg)
        }

        to {
            transform: rotate(1turn)
        }
    }
</style>