* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
    background: white;
    min-height: 100vh;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
}

header {
    text-align: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid #e0e0e0;
}

header h1 {
    color: #2c3e50;
    margin-bottom: 0.5rem;
    font-size: 2.5rem;
}

header p {
    color: #7f8c8d;
    font-size: 1.1rem;
}

main {
    display: grid;
    gap: 1.5rem;
}

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

label {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #2c3e50;
    font-size: 1.1rem;
}

textarea {
    width: 100%;
    padding: 15px;
    border: 2px solid #bdc3c7;
    border-radius: 8px;
    font-size: 14px;
    font-family: 'Courier New', monospace;
    line-height: 1.5;
    resize: vertical;
    transition: border-color 0.3s ease;
}

textarea:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

textarea#output-text {
    background-color: #f8f9fa;
}

.controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin: 1rem 0;
}

.primary-btn,
.secondary-btn,
.copy-btn {
    padding: 12px 24px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.primary-btn {
    background-color: #3498db;
    color: white;
}

.primary-btn:hover {
    background-color: #2980b9;
    transform: translateY(-1px);
}

.secondary-btn {
    background-color: #95a5a6;
    color: white;
}

.secondary-btn:hover {
    background-color: #7f8c8d;
    transform: translateY(-1px);
}

.output-container {
    position: relative;
}

.copy-btn {
    position: absolute;
    top: 10px;
    right: 10px;
    background-color: #27ae60;
    color: white;
    padding: 8px 16px;
    font-size: 14px;
    z-index: 1;
}

.copy-btn:hover:not(:disabled) {
    background-color: #219a52;
    transform: translateY(-1px);
}

.copy-btn:disabled {
    background-color: #bdc3c7;
    cursor: not-allowed;
    transform: none;
}

.copy-btn.copied {
    background-color: #e67e22;
}

footer {
    text-align: center;
    margin-top: 2rem;
    padding-top: 1rem;
    border-top: 1px solid #e0e0e0;
    color: #7f8c8d;
    font-size: 0.9rem;
}

.repo-info {
    margin-top: 0.8rem;
    padding-top: 0.8rem;
    border-top: 1px solid #f0f0f0;
}

.repo-info p {
    margin: 0;
    font-size: 0.85rem;
    color: #95a5a6;
}

.repo-info a {
    color: #3498db;
    text-decoration: none;
    transition: color 0.2s ease;
}

.repo-info a:hover {
    color: #2980b9;
    text-decoration: underline;
}

/* Responsive design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .controls {
        flex-direction: column;
        align-items: center;
    }
    
    .primary-btn,
    .secondary-btn {
        width: 200px;
    }
}