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

.modal {
    display: none;
    position: fixed;
    z-index: 1;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.7);
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #fefefe;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 800px;
}

.close {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: black;
}


header {
    background-color: #333;
    color: #fff;
    padding: 10px;
    text-align: center;
}

h1 {
    margin: 0;
}

nav ul {
    list-style: none;
    padding: 0;
}

nav ul li {
    display: inline;
    margin-right: 20px;
}

nav a {
    text-decoration: none;
    color: #fff;
    font-weight: bold;
}