.tutorial-modal {
    display: none; /* Hidden by default */
    position: fixed; /* Stay in place */
    z-index: 1000; /* Sit on top */
    left: 0;
    top: 0;
    width: 100%; /* Full width */
    height: 100%; /* Full height */
    overflow: auto; /* Enable scroll if needed */
    background-color: rgba(0,0,0,0.4); /* Black w/ opacity */
}

.tutorial-content {
    position: relative;
    margin: auto;
    padding: 20px;
    width: 80%;
    max-width: 800px;
    top: 50%;
    transform: translateY(-50%);
}

.tutorial-content img {
    width: 100%;
    height: auto;
}

.close-tutorial {
    color: red;
    float: right;
    font-size: 28px;
    font-weight: bold;
    position: absolute;
    top: 20px;
    right: 25px;
    background: none;
    border: none;
}

.close-tutorial:hover,
.close-tutorial:focus {
    color: darkred;
    text-decoration: none;
    cursor: pointer;
}