.progress-box {
    border: 1px solid gray;
    width: 200px;
    height: 40px;
}

#progress-indicator {
    width: 0%;
    background-color: blueviolet;
    height: 40px;
    transition-property: width;
    transition-duration: 0.2s;
}

button {
    margin: 5px;
    width: 60px;
    height: 30px;
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    font-weight: bold;
}