ball.css

body {
    margin: 0;
    font-size: 16px;
    font-family: Avenir, "Helvetica Neue", arial, sans-serif;
}

* {
    box-sizing: border-box;
}

.ball {
    height: 40px;
    width: 40px;
    border-radius: 50%;
    background: #ebebeb;
    position: absolute;
    transform-origin: center;
    transition: transform 0.3s;
}

.ball.highlighted:hover {
    border: 2px solid salmon;
}

.icon {
    background: #fff;
    border-radius: 50%;
    height: 44px;
    width: 44px;
}

.title {

}

.subtitle {
    font-size: 0.8rem;
}

.info {
    display: flex;
    align-items: center;
}

.info > *:not(:last-child) {
    margin-right: 8px;
}

.toolbar {
    background: #18b4f6;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px;
    color: #fff;
}

.toolbar > *:not(:last-child) {
    margin-right: 8px;
}

button {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background: transparent;
    outline: none;
    border: none;
    height: 44px;
    width: 44px;
    border-radius: 50%;
    padding: 4px;
    cursor: pointer;
}

button:hover {
    background: rgba(0,0,0,0.2);
}

button:active {
    background: rgba(0,0,0,0.5);
}