body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f7fa;
    margin: 0;
    padding: 0;
}

main {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem;
}

h1 {
    text-align: center;
    color: #4a6bff;
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.subtitle {
    text-align: center;
    color: #666;
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 3rem;
}

.input-section, .output-section {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

textarea {
    height: 300px;
    padding: 1rem;
    border: 1px solid #ddd;
    border-radius: 8px;
    resize: none;
    font-size: 1rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

textarea:focus {
    outline: none;
    border-color: #4a6bff;
}

button {
    padding: 0.8rem 1.5rem;
    background-color: #4a6bff;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #3a5bef;
}

#copyBtn {
    background-color: #28a745;
}

#copyBtn:hover {
    background-color: #218838;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 3rem;
}

.feature-card {
    background: white;
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

.feature-card h3 {
    margin-top: 0;
    color: #4a6bff;
}

@media (max-width: 768px) {
    .container {
        grid-template-columns: 1fr;
    }
}