<html>
<head>
    <style>
        .spinner {
            width: 100px;
            height: 100px;
            position: relative;
            margin: 100px auto;
        }
        .double-bounce1,
        .double-bounce2 {
            width: 100%;
            height: 100%;
            border-radius: 50%;
            background-color: #42a5f5;
            opacity: 0.6;
            position: absolute;
            top: 0;
            left: 0;
            -webkit-animation: sk-bounce 2.0s infinite ease-in-out;
            animation: sk-bounce 2.0s infinite ease-in-out;
        }
        .double-bounce2 {
            -webkit-animation-delay: -1.0s;
            animation-delay: -1.0s;
        }
        @keyframes sk-bounce {
            0%, 100% {
                transform: scale(0.0);
                -webkit-transform: scale(0.0);
            }
            50% {
                transform: scale(1.0);
                -webkit-transform: scale(1.0);
                background-color: #ec407a;
            }
        }
    </style>
</head>

<body>
    <div class="spinner">
        <div class="double-bounce1"></div>
        <div class="double-bounce2"></div>
    </div>
</body>

</html>

External CSS

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External JavaScript

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