:root {
            --bg-primary: #0a0a0f;
            --bg-secondary: #12121a;
            --bg-tertiary: #1a1a25;
            --accent-primary: #00d4aa;
            --accent-secondary: #00a88a;
            --accent-glow: rgba(0, 212, 170, 0.15);
            --text-primary: #f0f0f5;
            --text-secondary: #8888a0;
            --text-muted: #55556a;
            --border-color: #2a2a3a;
            --danger: #ff6b6b;
            --warning: #ffa94d;
            --success: #00d4aa;
        }

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

        body {
            font-family: 'DM Sans', sans-serif;
            background: var(--bg-primary);
            color: var(--text-primary);
            min-height: 100vh;
            overflow-x: hidden;
        }

        /* Background Pattern */
        body::before {
            content: '';
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: 
                radial-gradient(ellipse at 20% 20%, var(--accent-glow) 0%, transparent 50%),
                radial-gradient(ellipse at 80% 80%, rgba(100, 100, 255, 0.05) 0%, transparent 50%),
                repeating-linear-gradient(
                    0deg,
                    transparent,
                    transparent 50px,
                    rgba(255, 255, 255, 0.01) 50px,
                    rgba(255, 255, 255, 0.01) 51px
                ),
                repeating-linear-gradient(
                    90deg,
                    transparent,
                    transparent 50px,
                    rgba(255, 255, 255, 0.01) 50px,
                    rgba(255, 255, 255, 0.01) 51px
                );
            pointer-events: none;
            z-index: -1;
        }

        /* Header */
        header {
            padding: 1.5rem 2rem;
            border-bottom: 1px solid var(--border-color);
            background: rgba(10, 10, 15, 0.8);
            backdrop-filter: blur(10px);
            position: sticky;
            top: 0;
            z-index: 100;
        }

        .header-content {
            max-width: 1400px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 0.75rem;
        }

        .logo-icon {
            width: 40px;
            height: 40px;
            /* background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary)); */
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.25rem;
        }

        .logo-text {
            font-family: 'Space Mono', monospace;
            font-size: 1.8rem;
            font-weight: 700;
            letter-spacing: -0.5px;
        }

        .logo-text span {
            color: var(--accent-primary);
        }

        .security-badge {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            padding: 0.5rem 1rem;
            background: rgba(0, 212, 170, 0.1);
            border: 1px solid rgba(0, 212, 170, 0.3);
            border-radius: 100px;
            font-size: 0.8rem;
            color: var(--accent-primary);
        }

        .security-badge::before {
            content: '🔒';
        }

        /* Main Container */
        main {
            max-width: 1400px;
            margin: 0 auto;
            padding: 2rem;
        }

        /* Hero Section */
        .hero {
            text-align: center;
            /* padding: 3rem 0; */
            margin-bottom: 1rem;
        }

        .hero h1 {
            font-size: clamp(2rem, 5vw, 3.5rem);
            font-weight: 700;
            margin-bottom: 1rem;
            background: linear-gradient(135deg, var(--text-primary), var(--accent-primary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .hero p {
            font-size: 1.1rem;
            color: var(--text-secondary);
            max-width: 600px;
            margin: 0 auto;
            line-height: 1.7;
        }

        /* App Grid */
        .app-grid {
            display: grid;
            grid-template-columns: 1fr 350px;
            gap: 2rem;
            align-items: start;
        }

        @media (max-width: 1024px) {
            .app-grid {
                grid-template-columns: 1fr;
            }
        }

        /* Canvas Area */
        .canvas-area {
            background: var(--bg-secondary);
            border-radius: 20px;
            border: 1px solid var(--border-color);
            overflow: hidden;
        }

        .canvas-header {
            padding: 1rem 1.5rem;
            border-bottom: 1px solid var(--border-color);
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .canvas-title {
            font-family: 'Space Mono', monospace;
            font-size: 0.85rem;
            color: var(--text-secondary);
            text-transform: uppercase;
            letter-spacing: 1px;
        }

        .canvas-container {
            position: relative;
            min-height: 500px;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 2rem;
            background: 
                linear-gradient(45deg, var(--bg-tertiary) 25%, transparent 25%),
                linear-gradient(-45deg, var(--bg-tertiary) 25%, transparent 25%),
                linear-gradient(45deg, transparent 75%, var(--bg-tertiary) 75%),
                linear-gradient(-45deg, transparent 75%, var(--bg-tertiary) 75%);
            background-size: 20px 20px;
            background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
        }

        .drop-zone {
            width: 100%;
            height: 400px;
            border: 2px dashed var(--border-color);
            border-radius: 16px;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 1.5rem;
            cursor: pointer;
            transition: all 0.3s ease;
            background: rgba(10, 10, 15, 0.5);
        }

        .drop-zone:hover,
        .drop-zone.dragover {
            border-color: var(--accent-primary);
            background: rgba(0, 212, 170, 0.05);
        }

        .drop-zone.dragover {
            transform: scale(1.02);
        }

        .drop-icon {
            width: 80px;
            height: 80px;
            background: var(--bg-tertiary);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2rem;
            border: 2px solid var(--border-color);
        }

        .drop-text {
            text-align: center;
        }

        .drop-text h3 {
            font-size: 1.25rem;
            margin-bottom: 0.5rem;
        }

        .drop-text p {
            color: var(--text-secondary);
            font-size: 0.9rem;
        }

        .drop-text span {
            color: var(--accent-primary);
            text-decoration: underline;
            cursor: pointer;
        }

        #preview-canvas {
            max-width: 100%;
            max-height: 600px;
            border-radius: 8px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
            display: none;
        }

        .canvas-container.has-image .drop-zone {
            display: none;
        }

        .canvas-container.has-image #preview-canvas {
            display: block;
        }

        /* Controls Panel */
        .controls-panel {
            background: var(--bg-secondary);
            border-radius: 20px;
            border: 1px solid var(--border-color);
            overflow: hidden;
        }

        .panel-header {
            padding: 1.25rem 1.5rem;
            border-bottom: 1px solid var(--border-color);
            display: flex;
            align-items: center;
            gap: 0.75rem;
        }

        .panel-header h2 {
            font-size: 1rem;
            font-weight: 600;
        }

        .panel-content {
            padding: 1.5rem;
            display: flex;
            flex-direction: column;
            gap: 1.5rem;
        }

        /* Form Groups */
        .form-group {
            display: flex;
            flex-direction: column;
            gap: 0.5rem;
        }

        .form-group label {
            font-size: 0.85rem;
            color: var(--text-secondary);
            font-weight: 500;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .form-group input[type="text"],
        .form-group textarea,
        .form-group select {
            padding: 0.875rem 1rem;
            background: var(--bg-tertiary);
            border: 1px solid var(--border-color);
            border-radius: 10px;
            color: var(--text-primary);
            font-family: inherit;
            font-size: 0.95rem;
            transition: all 0.2s ease;
        }

        .form-group input:focus,
        .form-group textarea:focus,
        .form-group select:focus {
            outline: none;
            border-color: var(--accent-primary);
            box-shadow: 0 0 0 3px var(--accent-glow);
        }

        .form-group textarea {
            resize: vertical;
            min-height: 80px;
        }

        /* Range Slider */
        .range-group {
            display: flex;
            flex-direction: column;
            gap: 0.75rem;
        }

        .range-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .range-header label {
            font-size: 0.85rem;
            color: var(--text-secondary);
            font-weight: 500;
        }

        .range-value {
            font-family: 'Space Mono', monospace;
            font-size: 0.8rem;
            color: var(--accent-primary);
            background: rgba(0, 212, 170, 0.1);
            padding: 0.25rem 0.5rem;
            border-radius: 4px;
        }

        input[type="range"] {
            -webkit-appearance: none;
            appearance: none;
            width: 100%;
            height: 6px;
            background: var(--bg-tertiary);
            border-radius: 3px;
            cursor: pointer;
        }

        input[type="range"]::-webkit-slider-thumb {
            -webkit-appearance: none;
            appearance: none;
            width: 18px;
            height: 18px;
            background: var(--accent-primary);
            border-radius: 50%;
            cursor: pointer;
            transition: transform 0.2s ease;
        }

        input[type="range"]::-webkit-slider-thumb:hover {
            transform: scale(1.2);
        }

        /* Color Picker */
        .color-picker-group {
            display: flex;
            gap: 0.5rem;
        }

        .color-option {
            width: 32px;
            height: 32px;
            border-radius: 8px;
            cursor: pointer;
            border: 2px solid transparent;
            transition: all 0.2s ease;
        }

        .color-option:hover {
            transform: scale(1.1);
        }

        .color-option.active {
            border-color: var(--text-primary);
            box-shadow: 0 0 0 2px var(--bg-primary);
        }

        .color-option.white { background: rgba(255, 255, 255, 0.9); }
        .color-option.black { background: rgba(0, 0, 0, 0.7); }
        .color-option.red { background: rgba(255, 100, 100, 0.8); }
        .color-option.blue { background: rgba(100, 150, 255, 0.8); }

        /* Toggle Switch */
        .toggle-group {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 0.75rem 0;
        }

        .toggle-label {
            font-size: 0.85rem;
            color: var(--text-secondary);
        }

        .toggle-switch {
            position: relative;
            width: 48px;
            height: 26px;
            background: var(--bg-tertiary);
            border-radius: 13px;
            cursor: pointer;
            transition: background 0.3s ease;
        }

        .toggle-switch::after {
            content: '';
            position: absolute;
            top: 3px;
            left: 3px;
            width: 20px;
            height: 20px;
            background: var(--text-secondary);
            border-radius: 50%;
            transition: all 0.3s ease;
        }

        .toggle-switch.active {
            background: var(--accent-primary);
        }

        .toggle-switch.active::after {
            left: 25px;
            background: var(--bg-primary);
        }

        /* Buttons */
        .btn {
            padding: 1rem 1.5rem;
            border: none;
            border-radius: 12px;
            font-family: inherit;
            font-size: 0.95rem;
            font-weight: 600;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            transition: all 0.2s ease;
        }

        .btn-primary {
            background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
            color: var(--bg-primary);
        }

        .btn-primary:hover {
            transform: translateY(-2px);
            box-shadow: 0 10px 30px rgba(0, 212, 170, 0.3);
        }

        .btn-primary:disabled {
            opacity: 0.5;
            cursor: not-allowed;
            transform: none;
            box-shadow: none;
        }

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

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

        .btn-danger {
            background: rgba(255, 107, 107, 0.1);
            color: var(--danger);
            border: 1px solid rgba(255, 107, 107, 0.3);
        }

        .btn-danger:hover {
            background: rgba(255, 107, 107, 0.2);
        }

        .btn-group {
            display: flex;
            gap: 0.75rem;
            margin-top: 0.5rem;
        }

        .btn-group .btn {
            flex: 1;
        }

        /* Section Divider */
        .divider {
            height: 1px;
            background: var(--border-color);
            margin: 0.5rem 0;
        }

        /* Presets */
        .presets-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 0.5rem;
        }

        .preset-btn {
            padding: 0.75rem;
            background: var(--bg-tertiary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            color: var(--text-secondary);
            font-size: 0.8rem;
            cursor: pointer;
            transition: all 0.2s ease;
            text-align: center;
        }

        .preset-btn:hover {
            border-color: var(--accent-primary);
            color: var(--accent-primary);
        }

        /* Privacy Notice */
        .privacy-notice {
            margin-top: 3rem;
            padding: 2rem;
            background: linear-gradient(135deg, rgba(0, 212, 170, 0.05), rgba(100, 100, 255, 0.05));
            border: 1px solid var(--border-color);
            border-radius: 16px;
            text-align: center;
        }

        .privacy-notice h3 {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            margin-bottom: 1rem;
            color: var(--accent-primary);
        }

        .privacy-notice p {
            color: var(--text-secondary);
            font-size: 0.9rem;
            line-height: 1.7;
            max-width: 600px;
            margin: 0 auto;
        }

        .privacy-features {
            display: flex;
            justify-content: center;
            gap: 2rem;
            margin-top: 1.5rem;
            flex-wrap: wrap;
        }

        .privacy-feature {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            color: var(--text-secondary);
            font-size: 0.85rem;
        }

        .privacy-feature::before {
            content: '✓';
            color: var(--accent-primary);
            font-weight: bold;
        }

        /* Footer */
        footer {
            text-align: center;
            padding: 2rem;
            color: var(--text-muted);
            font-size: 0.85rem;
            border-top: 1px solid var(--border-color);
            margin-top: 3rem;
        }

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

        .canvas-area,
        .controls-panel {
            animation: fadeIn 0.5s ease-out;
        }

        .controls-panel {
            animation-delay: 0.1s;
        }

        /* Responsive */
        @media (max-width: 768px) {
            main {
                padding: 1rem;
            }

            .hero {
                padding: 0.1rem 0;
            }

            .header-content {
                flex-direction: column;
                gap: 1rem;
            }

            .privacy-features {
                flex-direction: column;
                align-items: center;
                gap: 0.75rem;
            }
        }

        /* Hidden file input */
        #file-input {
            display: none;
        }

        /* Masking Tools */
        .tools-bar {
            display: none;
            padding: 1rem 1.5rem;
            border-bottom: 1px solid var(--border-color);
            background: var(--bg-tertiary);
            gap: 0.5rem;
            flex-wrap: wrap;
            align-items: center;
        }

        .tools-bar.visible {
            display: flex;
        }

        .tool-btn {
            padding: 0.6rem 1rem;
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            color: var(--text-secondary);
            font-size: 0.85rem;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 0.4rem;
            transition: all 0.2s ease;
        }

        .tool-btn:hover {
            border-color: var(--accent-primary);
            color: var(--text-primary);
        }

        .tool-btn.active {
            background: var(--accent-primary);
            border-color: var(--accent-primary);
            color: var(--bg-primary);
        }

        .tool-separator {
            width: 1px;
            height: 24px;
            background: var(--border-color);
            margin: 0 0.5rem;
        }

        .tool-group {
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .tool-group label {
            font-size: 0.8rem;
            color: var(--text-secondary);
        }

        .tool-group input[type="range"] {
            width: 80px;
            height: 4px;
        }

        .tool-group select {
            padding: 0.4rem 0.6rem;
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 6px;
            color: var(--text-primary);
            font-size: 0.8rem;
        }

        /* Canvas cursor styles */
        .canvas-container.tool-brush {
            cursor: crosshair;
        }

        .canvas-container.tool-rect {
            cursor: crosshair;
        }

        .canvas-container.tool-blur {
            cursor: crosshair;
        }

        .canvas-container.tool-eraser {
            cursor: cell;
        }

        /* Undo/Redo buttons */
        .history-btn {
            padding: 0.5rem;
            background: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: 6px;
            color: var(--text-secondary);
            cursor: pointer;
            transition: all 0.2s ease;
            font-size: 1rem;
            line-height: 1;
        }

        .history-btn:hover:not(:disabled) {
            border-color: var(--accent-primary);
            color: var(--text-primary);
        }

        .history-btn:disabled {
            opacity: 0.3;
            cursor: not-allowed;
        }

        /* Mask color options in toolbar */
        .mask-color-btn {
            width: 24px;
            height: 24px;
            border-radius: 4px;
            border: 2px solid transparent;
            cursor: pointer;
            transition: all 0.2s ease;
        }

        .mask-color-btn:hover {
            transform: scale(1.1);
        }

        .mask-color-btn.active {
            border-color: var(--accent-primary);
        }

        .mask-color-btn.mc-black { background: #000; }
        .mask-color-btn.mc-white { background: #fff; border: 1px solid var(--border-color); }
        .mask-color-btn.mc-gray { background: #888; }
        .mask-color-btn.mc-red { background: #d00; }
        .mask-color-btn.mc-blur { 
            background: linear-gradient(45deg, #666 25%, #888 25%, #888 50%, #666 50%, #666 75%, #888 75%);
            background-size: 8px 8px;
        }

        /* Instructions tooltip */
        .tool-instructions {
            font-size: 0.75rem;
            color: var(--text-muted);
            margin-left: auto;
            padding: 0.4rem 0.8rem;
            background: var(--bg-secondary);
            border-radius: 4px;
        }

        /* Pattern selector */
        .pattern-selector {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 0.5rem;
        }

        .pattern-btn {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 0.4rem;
            padding: 0.75rem 0.5rem;
            background: var(--bg-tertiary);
            border: 2px solid var(--border-color);
            border-radius: 10px;
            color: var(--text-secondary);
            font-size: 0.75rem;
            cursor: pointer;
            transition: all 0.2s ease;
        }

        .pattern-btn:hover {
            border-color: var(--accent-primary);
            color: var(--text-primary);
        }

        .pattern-btn.active {
            border-color: var(--accent-primary);
            background: rgba(0, 212, 170, 0.1);
            color: var(--accent-primary);
        }

        .pattern-btn svg {
            width: 32px;
            height: 32px;
            stroke: currentColor;
            fill: none;
            stroke-width: 1.5;
        }

        .pattern-btn.active svg {
            stroke: var(--accent-primary);
        }

        /* Loading state */
        .loading {
            position: relative;
            pointer-events: none;
        }

        .loading::after {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 24px;
            height: 24px;
            margin: -12px 0 0 -12px;
            border: 3px solid var(--bg-tertiary);
            border-top-color: var(--accent-primary);
            border-radius: 50%;
            animation: spin 0.8s linear infinite;
        }

        @keyframes spin {
            to { transform: rotate(360deg); }
        }