/* ============================================
   Global Styles & Reset
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Color Palette */
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --success-gradient: linear-gradient(135deg, #2ed573 0%, #1abc9c 100%);
    --danger-gradient: linear-gradient(135deg, #ff6b6b 0%, #feca57 100%);
    --info-gradient: linear-gradient(135deg, #5f27cd 0%, #341f97 100%);
    
    /* Colors */
    --primary-color: #4facfe;
    --secondary-color: #667eea;
    --success-color: #2ed573;
    --danger-color: #ff6b6b;
    --info-color: #5f27cd;
    --warning-color: #feca57;
    
    /* Neutrals */
    --text-primary: #2c3e50;
    --text-secondary: #666;
    --text-muted: #999;
    --background: #f5f7fa;
    --card-background: #ffffff;
    --border-color: #e1e5e9;
    --hover-background: #f8f9ff;
    
    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 20px;
    --spacing-lg: 30px;
    --spacing-xl: 40px;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-pill: 50px;
    
    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 5px 15px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Helvetica Neue", Arial, sans-serif;
    background: var(--primary-gradient);
    min-height: 100vh;
    padding: var(--spacing-md);
    line-height: 1.6;
    color: var(--text-primary);
    overflow-x: hidden;
}

/* ============================================
   Container & Layout
   ============================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    background: var(--card-background);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ============================================
   Header
   ============================================ */
.header {
    background: var(--secondary-gradient);
    color: white;
    padding: var(--spacing-xl);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.header::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: headerPulse 15s ease-in-out infinite;
}

@keyframes headerPulse {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(10%, 10%); }
}

.header-content {
    position: relative;
    z-index: 1;
}

.header h1 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
    font-weight: 700;
}

.header p {
    font-size: 1.1rem;
    opacity: 0.95;
    margin-bottom: 0;
}

.github-link {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: rgba(255, 255, 255, 0.2);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-pill);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all var(--transition-base);
    backdrop-filter: blur(10px);
    font-weight: 600;
    z-index: 2;
}

.github-link:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.github-link svg {
    width: 24px;
    height: 24px;
}

/* ============================================
   Content Area
   ============================================ */
.content {
    padding: var(--spacing-xl);
}

.card {
    background: var(--card-background);
    border-radius: var(--radius-md);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
    border: 2px solid var(--border-color);
    transition: all var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--primary-color);
}

.card h2 {
    color: var(--text-primary);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-weight: 600;
}

.card h2 .icon {
    width: 28px;
    height: 28px;
    color: var(--primary-color);
}

.section-description {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    font-size: 0.95rem;
}

/* ============================================
   Configuration Section
   ============================================ */
.config-section {
    background: linear-gradient(135deg, #f8f9ff 0%, #f0f4ff 100%);
    border: 2px dashed var(--primary-color);
}

.config-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.config-item {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.config-item label {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.config-item input[type="text"],
.config-item input[type="number"] {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    transition: all var(--transition-base);
    background: white;
}

.config-item input[type="text"]:focus,
.config-item input[type="number"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 172, 254, 0.1);
}

.config-item input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

.help-text {
    color: var(--text-muted);
    font-size: 0.85rem;
    font-style: italic;
}

/* Accordion */
.config-advanced {
    margin-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
    padding-top: var(--spacing-md);
}

.accordion-btn {
    width: 100%;
    background: transparent;
    border: none;
    padding: var(--spacing-sm) 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    color: var(--primary-color);
    transition: all var(--transition-base);
}

.accordion-btn:hover {
    color: var(--secondary-color);
}

.accordion-btn .chevron {
    width: 20px;
    height: 20px;
    transition: transform var(--transition-base);
}

.accordion-btn[aria-expanded="true"] .chevron {
    transform: rotate(180deg);
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-base);
}

.accordion-content.open {
    max-height: 500px;
    padding-top: var(--spacing-md);
}

/* ============================================
   Input Section
   ============================================ */
.input-section {
    background: linear-gradient(135deg, #fff8f0 0%, #fff4e6 100%);
    border: 2px dashed var(--warning-color);
}

.file-upload-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    padding: var(--spacing-md);
    background: white;
    border-radius: var(--radius-sm);
    border: 2px dashed var(--border-color);
}

.upload-btn {
    background: var(--secondary-gradient);
    color: white;
    border: none;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-pill);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.upload-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.upload-btn .icon {
    width: 20px;
    height: 20px;
}

.or-divider {
    color: var(--text-muted);
    font-size: 0.9rem;
    font-style: italic;
}

textarea {
    width: 100%;
    min-height: 250px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: var(--spacing-md);
    font-size: 0.95rem;
    font-family: "Courier New", "Consolas", monospace;
    line-height: 1.6;
    resize: vertical;
    transition: all var(--transition-base);
    background: white;
}

textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 172, 254, 0.1);
}

.data-preview {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    background: white;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    display: none;
}

.data-preview.visible {
    display: block;
}

/* ============================================
   Buttons
   ============================================ */
.button-group {
    display: flex;
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
    flex-wrap: wrap;
}

.btn {
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-pill);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
    min-width: 160px;
    justify-content: center;
}

.btn .icon {
    width: 20px;
    height: 20px;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background: var(--secondary-gradient);
    color: white;
}

.btn-secondary {
    background: linear-gradient(135deg, #95a5a6 0%, #7f8c8d 100%);
    color: white;
}

.btn-success {
    background: var(--success-gradient);
    color: white;
}

.btn-danger {
    background: var(--danger-gradient);
    color: white;
}

.btn-info {
    background: var(--info-gradient);
    color: white;
}

/* ============================================
   Results Section
   ============================================ */
.result-section {
    background: linear-gradient(135deg, #f0fff4 0%, #e6f9f0 100%);
    border: 2px solid var(--success-color);
}

.result-section.hidden {
    display: none;
}

.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.stat-card {
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: all var(--transition-base);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.stat-card h3 {
    color: var(--primary-color);
    font-size: 2.5rem;
    margin-bottom: var(--spacing-xs);
    font-weight: 700;
}

.stat-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin: 0;
}

.result-actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.result-actions .btn {
    min-width: auto;
    flex: 1;
}

/* ============================================
   Table
   ============================================ */
.table-container {
    background: white;
    border-radius: var(--radius-sm);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    overflow-x: auto;
}

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

th, td {
    padding: var(--spacing-sm) var(--spacing-md);
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

th {
    background: var(--secondary-gradient);
    color: white;
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    position: sticky;
    top: 0;
    z-index: 10;
}

tbody tr {
    transition: background var(--transition-fast);
}

tbody tr:hover {
    background: var(--hover-background);
}

tbody tr:nth-child(even) {
    background: #fafafa;
}

tbody tr:nth-child(even):hover {
    background: #f0f5ff;
}

td {
    font-size: 0.95rem;
}

/* ============================================
   Footer
   ============================================ */
.footer {
    background: #f8f9fa;
    padding: var(--spacing-lg);
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.footer p {
    margin: var(--spacing-xs) 0;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer a:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

/* ============================================
   Notification Toast
   ============================================ */
.notification {
    position: fixed;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: var(--success-color);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-pill);
    font-weight: 600;
    box-shadow: var(--shadow-lg);
    transform: translateX(400px);
    transition: transform var(--transition-base);
    z-index: 1000;
    max-width: 350px;
}

.notification.show {
    transform: translateX(0);
}

.notification.error {
    background: var(--danger-color);
}

.notification.info {
    background: var(--info-color);
}

.notification.warning {
    background: var(--warning-color);
    color: var(--text-primary);
}

/* ============================================
   Utility Classes
   ============================================ */
.hidden {
    display: none !important;
}

.icon {
    flex-shrink: 0;
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 768px) {
    body {
        padding: var(--spacing-xs);
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .header p {
        font-size: 1rem;
    }
    
    .github-link {
        position: static;
        margin-top: var(--spacing-md);
        display: inline-flex;
    }
    
    .content {
        padding: var(--spacing-md);
    }
    
    .card {
        padding: var(--spacing-md);
    }
    
    .config-grid {
        grid-template-columns: 1fr;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
    
    .result-actions {
        flex-direction: column;
    }
    
    .stats {
        grid-template-columns: 1fr;
    }
    
    .notification {
        right: var(--spacing-xs);
        left: var(--spacing-xs);
        max-width: none;
    }
}

@media (max-width: 480px) {
    .header h1 {
        font-size: 1.5rem;
    }
    
    table {
        font-size: 0.85rem;
    }
    
    th, td {
        padding: var(--spacing-xs) var(--spacing-sm);
    }
}

/* ============================================
   Print Styles
   ============================================ */
@media print {
    body {
        background: white;
        padding: 0;
    }
    
    .container {
        box-shadow: none;
    }
    
    .header,
    .config-section,
    .input-section,
    .button-group,
    .result-actions,
    .footer,
    .notification {
        display: none !important;
    }
    
    .result-section {
        border: 1px solid #000;
        page-break-inside: avoid;
    }
    
    table {
        page-break-inside: auto;
    }
    
    tr {
        page-break-inside: avoid;
        page-break-after: auto;
    }
}