* {
    padding: 0;
    margin: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, Helvetica, sans-serif;
}

main {
    max-width: 600px;
    margin: 50px auto;
    text-align: center;
    line-height: 3;
}

.color-box {
    font-size: 2rem;
    font-weight: bold;
}

button {
    padding: 15px 30px;
    border: none;
    border-radius: 5px;
    background-color: green;
    color: white;
}

footer {
    background-color: black;
    color: white;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;

}