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

:root {
    /* Colors */
    --primary: #0ea5a4;
    --primary-dark: #0c8584;
    --primary-light: #10b5b4;
    --accent: #fb923c;
    --accent-dark: #f97316;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-hint: #94a3b8;
    --border: #e2e8f0;
    --border-hover: #cbd5e1;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Typography */
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Poppins', 'Inter', sans-serif;
}

body {
    font-family: var(--font-body);
    background: var(--bg);
    color: var(--text-primary);
    font-size: 14px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Header */
.header {
    background: var(--card-bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo-text {
    font-family: var(--font-heading);
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
}

.header-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.icon-btn {
    background: transparent;
    border: none;
    padding: var(--spacing-sm);
    cursor: pointer;
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.icon-btn:hover {
    background: var(--bg);
    color: var(--primary);
}

.icon-btn:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Main Content */
.main-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-2xl) var(--spacing-xl);
    min-height: calc(100vh - 200px);
}

.container {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: var(--spacing-2xl);
}

/* Hero Section */
.hero-text {
    margin-bottom: var(--spacing-xl);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.hero-subtitle {
    font-size: 16px;
    color: var(--text-secondary);
}

/* Upload Section */
.upload-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.upload-card {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.upload-label {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.label-icon {
    font-size: 20px;
}

.upload-zone {
    background: var(--card-bg);
    border: 2px dashed var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl) var(--spacing-lg);
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.upload-zone:hover {
    border-color: var(--primary);
    background: rgba(14, 165, 164, 0.02);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.upload-zone:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
    border-color: var(--primary);
}

.upload-zone.drag-over {
    border-color: var(--primary);
    background: rgba(14, 165, 164, 0.05);
    transform: scale(1.02);
}

.file-input {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    top: 0;
    left: 0;
}

.upload-content {
    text-align: center;
    pointer-events: none;
}

.upload-icon {
    color: var(--text-hint);
    margin-bottom: var(--spacing-md);
}

.upload-text {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

.upload-link {
    color: var(--primary);
    font-weight: 600;
}

.upload-hint {
    font-size: 12px;
    color: var(--text-hint);
}

/* Preview */
.preview-container {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    animation: fadeIn 0.3s ease;
}

.preview-image {
    width: 100%;
    height: 150px;
    object-fit: cover;
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
}

.preview-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.btn-small {
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: var(--radius-md);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    transition: all 0.2s;
    flex: 1;
    justify-content: center;
}

.btn-secondary {
    background: var(--bg);
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--border);
    color: var(--text-primary);
}

.btn-danger {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

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

/* Tip Box */
.tip-box {
    background: rgba(14, 165, 164, 0.05);
    border: 1px solid rgba(14, 165, 164, 0.2);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
}

.tip-box svg {
    flex-shrink: 0;
    color: var(--primary);
}

/* Controls Section */
.controls-section {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-sm);
}

.control-group {
    margin-bottom: var(--spacing-lg);
}

.control-group:last-child {
    margin-bottom: 0;
}

.control-label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.control-value {
    color: var(--primary);
    font-weight: 700;
}

.select-input {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-family: var(--font-body);
    background: var(--card-bg);
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.2s;
}

.select-input:hover {
    border-color: var(--border-hover);
}

.select-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(14, 165, 164, 0.1);
}

.slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--border);
    outline: none;
    -webkit-appearance: none;
    appearance: none;
    cursor: pointer;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    box-shadow: var(--shadow-md);
    transition: all 0.2s;
}

.slider::-webkit-slider-thumb:hover {
    transform: scale(1.1);
    background: var(--primary-dark);
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-md);
    transition: all 0.2s;
}

.slider::-moz-range-thumb:hover {
    transform: scale(1.1);
    background: var(--primary-dark);
}

/* Generate Button */
.btn-generate {
    width: 100%;
    padding: var(--spacing-lg) var(--spacing-xl);
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: 16px;
    font-weight: 700;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-md);
    margin-bottom: var(--spacing-lg);
}

.btn-generate:not(:disabled):hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-generate:not(:disabled):active {
    transform: translateY(0);
}

.btn-generate:disabled {
    background: var(--border);
    color: var(--text-hint);
    cursor: not-allowed;
    box-shadow: none;
}

.btn-generate:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Advanced Controls */
.advanced-toggle {
    margin-bottom: var(--spacing-md);
}

.toggle-btn {
    width: 100%;
    background: transparent;
    border: none;
    padding: var(--spacing-md) 0;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    transition: color 0.2s;
}

.toggle-btn:hover {
    color: var(--primary);
}

.toggle-btn .chevron {
    transition: transform 0.3s;
}

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

.advanced-panel {
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border);
    animation: slideDown 0.3s ease;
}

.checkbox-group {
    margin-top: var(--spacing-lg);
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    cursor: pointer;
    font-size: 13px;
    color: var(--text-secondary);
}

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

/* Right Panel - Result Section */
.right-panel {
    position: sticky;
    top: 100px;
    height: fit-content;
}

.result-section {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
}

.result-empty {
    padding: var(--spacing-2xl);
    text-align: center;
    min-height: 500px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.result-empty svg {
    margin-bottom: var(--spacing-xl);
}

.result-empty h3 {
    font-family: var(--font-heading);
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.result-empty p {
    font-size: 14px;
    color: var(--text-secondary);
}

.result-content {
    animation: fadeIn 0.5s ease;
}

/* Tabs */
.result-tabs {
    display: flex;
    border-bottom: 1px solid var(--border);
    background: var(--bg);
}

.tab-btn {
    flex: 1;
    padding: var(--spacing-lg);
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    border-bottom: 2px solid transparent;
    transition: all 0.2s;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: rgba(14, 165, 164, 0.03);
}

.tab-btn.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.tab-btn:focus {
    outline: 2px solid var(--primary);
    outline-offset: -2px;
}

/* Result Canvas */
.result-canvas {
    position: relative;
    min-height: 400px;
    background: var(--bg);
}

.tab-content {
    display: none;
    padding: var(--spacing-xl);
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

.result-image {
    width: 100%;
    height: auto;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

/* Comparison Slider */
.comparison-slider {
    position: absolute;
    inset: 0;
    background: white;
    z-index: 10;
}

.slider-container {
    position: relative;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.slider-before,
.slider-after {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.slider-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 50%;
    height: 100%;
    overflow: hidden;
    border-right: 3px solid white;
}

.slider-handle {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 100%;
    cursor: ew-resize;
    z-index: 20;
    display: flex;
    align-items: center;
    justify-content: center;
}

.slider-line {
    position: absolute;
    width: 3px;
    height: 100%;
    background: white;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);
}

.slider-button {
    position: absolute;
    width: 48px;
    height: 48px;
    background: var(--primary);
    border-radius: 50%;
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 2px;
}

.slider-button svg {
    width: 16px;
    height: 16px;
}

.toggle-slider-btn {
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(10px);
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all 0.2s;
    z-index: 30;
}

.toggle-slider-btn:hover {
    background: rgba(0, 0, 0, 0.85);
    transform: scale(1.05);
}

/* Result Actions */
.result-actions {
    padding: var(--spacing-xl);
    border-top: 1px solid var(--border);
    background: var(--bg);
}

.caption-input {
    width: 100%;
    padding: var(--spacing-md);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-family: var(--font-body);
    margin-bottom: var(--spacing-md);
    transition: all 0.2s;
}

.caption-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(14, 165, 164, 0.1);
}

.action-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: var(--spacing-md);
}

.btn-action {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    transition: all 0.2s;
    border: none;
}

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

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

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

.btn-primary:hover {
    background: var(--primary-dark);
}

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

.btn-secondary:hover {
    background: var(--accent-dark);
}

.btn-outline {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    background: var(--bg);
    color: var(--text-primary);
    border-color: var(--border-hover);
}

/* Footer */
.footer {
    background: var(--card-bg);
    border-top: 1px solid var(--border);
    padding: var(--spacing-xl);
    margin-top: var(--spacing-2xl);
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
    text-align: center;
}

.privacy-note {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.privacy-note svg {
    flex-shrink: 0;
    color: var(--primary);
}

.copyright {
    font-size: 12px;
    color: var(--text-hint);
}

/* Progress Modal */
.modal {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background: var(--card-bg);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    width: 90%;
    max-width: 500px;
    animation: slideUp 0.3s ease;
}

.modal-header {
    padding: var(--spacing-xl);
    border-bottom: 1px solid var(--border);
}

.modal-header h3 {
    font-family: var(--font-heading);
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
}

.modal-body {
    padding: var(--spacing-xl);
}

.progress-bar {
    width: 100%;
    height: 12px;
    background: var(--border);
    border-radius: 6px;
    overflow: hidden;
    margin-bottom: var(--spacing-lg);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, var(--accent) 100%);
    border-radius: 6px;
    transition: width 0.5s ease;
    animation: shimmer 2s infinite;
    width: 0%;
}

.progress-text {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.progress-hint {
    font-size: 12px;
    color: var(--text-hint);
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-xl);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    min-width: 300px;
    max-width: 400px;
    z-index: 1001;
    animation: slideInRight 0.3s ease;
}

.toast-icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.toast.success .toast-icon {
    background: var(--success);
}

.toast.error .toast-icon {
    background: var(--error);
}

.toast.warning .toast-icon {
    background: var(--warning);
}

.toast.success .toast-icon::after {
    content: '✓';
    color: white;
    font-size: 14px;
    font-weight: bold;
}

.toast.error .toast-icon::after {
    content: '✕';
    color: white;
    font-size: 14px;
    font-weight: bold;
}

.toast.warning .toast-icon::after {
    content: '!';
    color: white;
    font-size: 14px;
    font-weight: bold;
}

.toast-message {
    font-size: 14px;
    color: var(--text-primary);
    flex: 1;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes shimmer {
    0% {
        background-position: -500px 0;
    }
    100% {
        background-position: 500px 0;
    }
}

/* Mobile Responsive */
@media (max-width: 1024px) {
    .container {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }
    
    .right-panel {
        position: static;
    }
}

@media (max-width: 768px) {
    .main-content {
        padding: var(--spacing-lg) var(--spacing-md);
    }
    
    .header-content {
        padding: var(--spacing-md);
    }
    
    .logo-text {
        font-size: 16px;
    }
    
    .hero-title {
        font-size: 24px;
    }
    
    .hero-subtitle {
        font-size: 14px;
    }
    
    .upload-section {
        grid-template-columns: 1fr;
    }
    
    .upload-zone {
        min-height: 180px;
        padding: var(--spacing-xl) var(--spacing-md);
    }
    
    .action-buttons {
        grid-template-columns: 1fr;
    }
    
    .result-tabs {
        flex-wrap: wrap;
    }
    
    .tab-btn {
        flex: 1 0 33.333%;
        font-size: 13px;
        padding: var(--spacing-md);
    }
    
    .toast {
        bottom: var(--spacing-md);
        right: var(--spacing-md);
        left: var(--spacing-md);
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .preview-actions {
        flex-direction: column;
    }
    
    .btn-small {
        width: 100%;
    }
    
    .result-canvas {
        min-height: 300px;
    }
}

/* Accessibility - High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --border: #000000;
        --text-secondary: #000000;
    }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .controls-section,
    .result-actions {
        display: none;
    }
    
    .result-image {
        max-width: 100%;
        page-break-inside: avoid;
    }
}