body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

header {
    background: #333;
    color: #fff;
    text-align: center;
    padding: 1rem;
}

nav {
    background: #444;
    padding: 0.5rem;
}

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

nav ul li {
    display: inline;
    margin-right: 10px;
}

nav ul li a {
    color: #fff;
    text-decoration: none;
}

main {
    padding: 20px;
}

section {
    margin-bottom: 20px;
}

form {
    display: flex;
    flex-direction: column;
    max-width: 500px;
    margin-bottom: 20px;
}

input, textarea {
    margin-bottom: 10px;
    padding: 5px;
}

button {
    background: #333;
    color: #fff;
    padding: 10px;
    border: none;
    cursor: pointer;
}

button:hover {
    background: #555;
}

table {
    width: 100%;
    border-collapse: collapse;
}

table, th, td {
    border: 1px solid #ddd;
}

th, td {
    text-align: left;
    padding: 8px;
}

tr:nth-child(even) {
    background-color: #f2f2f2;
}

#test-result {
    margin-top: 20px;
}

#test-result img {
    max-width: 100%;
    height: auto;
}