body {
    font-family: 'Segoe UI', Arial, sans-serif;
    background-color: #f4f6f8;
    color: #333;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 900px;
    margin: 50px auto;
    padding: 30px;
    background-color: #fff;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    border-radius: 10px;
    text-align: center;
}

h1 {
    margin-bottom: 5px;
}

.subtitle {
    margin-top: 0;
    font-weight: normal;
    color: #666;
}

.input-section, .output-section {
    margin: 20px 0;
    text-align: left;
}

textarea {
    width: 100%;
    height: 120px;
    padding: 12px;
    font-size: 16px;
    margin-top: 5px;
    border-radius: 6px;
    border: 1px solid #ccc;
    resize: vertical;
    box-sizing: border-box;
}

textarea::placeholder {
    color: #888;
    opacity: 0.7;
}

button {
    display: block;
    margin: 15px auto 0 auto;
    padding: 12px 24px;
    font-size: 16px;
    background-color: #4a90e2;
    color: #fff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

button:hover {
    background-color: #357ab8;
}

.output-section pre {
    background-color: #f0f0f0;
    padding: 15px;
    border-radius: 6px;
    min-height: 70px;
    overflow-x: auto;
}

footer {
    margin-top: 40px;
    font-size: 14px;
    color: #999;
}