body {
    font-family: 'Georgia', serif;
    line-height: 1.6;
    color: #333;
    max-width: 800px;
    margin: 40px auto;
    padding: 0 20px;
    background-color: #fff;
}

header {
    margin-bottom: 40px;
    border-bottom: 1px solid #eee;
    padding-bottom: 20px;
}

h1 {
    font-size: 2.5rem;
    font-weight: normal;
    margin: 0;
    color: #000;
}

.subtitle {
    font-style: italic;
    color: #666;
    margin-top: 5px;
}

.container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

label {
    font-weight: bold;
    font-size: 1.1rem;
}

input[type="text"] {
    font-family: 'Courier New', Courier, monospace;
    font-size: 1.2rem;
    padding: 12px;
    border: 1px solid #ccc;
    border-radius: 4px;
    width: 100%;
    box-sizing: border-box;
}

button {
    background-color: #004499;
    color: white;
    padding: 12px 24px;
    border: none;
    border-radius: 4px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background-color 0.2s;
    align-self: flex-start;
}

button:hover {
    background-color: #003377;
}

#result {
    margin-top: 30px;
    padding: 20px;
    border-radius: 4px;
    display: none;
    font-size: 1.5rem;
    text-align: center;
    border: 1px solid transparent;
}

#result.safe {
    display: block;
    background-color: #e6f4ea;
    color: #1e7e34;
    border-color: #c3e6cb;
}

#result.dangerous {
    display: block;
    background-color: #fce8e6;
    color: #d93025;
    border-color: #f5c6cb;
}

#result.error {
    display: block;
    background-color: #fff3cd;
    color: #856404;
    border-color: #ffeeba;
}

.examples {
    margin-top: 50px;
}

.examples h3 {
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
    font-weight: normal;
}

.example-list {
    list-style: none;
    padding: 0;
}

.example-list li {
    margin-bottom: 15px;
}

.example-link {
    color: #004499;
    text-decoration: none;
    font-family: 'Courier New', Courier, monospace;
    border-bottom: 1px dotted #004499;
    cursor: pointer;
}

.example-link:hover {
    color: #002266;
    border-bottom-style: solid;
}

.example-desc {
    display: block;
    font-size: 0.9rem;
    color: #666;
    margin-top: 2px;
}

footer {
    margin-top: 80px;
    font-size: 0.8rem;
    color: #999;
    text-align: center;
    border-top: 1px solid #eee;
    padding-top: 20px;
}