/* CSS Variables - TechTools Theme */
:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #1a1a2e;
    --bg-hover: #232338;
    --border-color: #2a2a40;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent-primary: #6366f1;
    --accent-secondary: #8b5cf6;
    --accent-hover: #818cf8;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --transition: all 0.2s ease;
}

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

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

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-left, .header-right {
    flex: 1;
    display: flex;
    align-items: center;
}

.header-right {
    justify-content: flex-end;
    gap: 0.75rem;
}

.header-center {
    flex: 2;
    text-align: center;
}

.header h1 {
    font-size: 1.4rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

.header h1 i {
    color: var(--accent-primary);
}

.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    font-size: 0.9rem;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

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

.btn-primary:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

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

.btn-secondary:hover:not(:disabled) {
    background: var(--border-color);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-full {
    width: 100%;
    justify-content: center;
    padding: 0.75rem;
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* Upload Section */
.upload-section {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.upload-area {
    width: 100%;
    max-width: 600px;
    padding: 4rem 2rem;
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
}

.upload-area:hover {
    border-color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.05);
}

.upload-area.dragover {
    border-color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.1);
}

.upload-icon {
    font-size: 4rem;
    color: var(--accent-primary);
    margin-bottom: 1.5rem;
}

.upload-area h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.upload-area p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.upload-formats {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Editor Section */
.editor-section {
    flex: 1;
    display: flex;
    flex-direction: column;
}

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

.editor-layout {
    display: grid;
    grid-template-columns: 280px 1fr 260px;
    gap: 1rem;
    padding: 1rem;
    flex: 1;
    min-height: 0;
}

/* Tools Panel */
.tools-panel {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    overflow-y: auto;
    max-height: calc(100vh - 120px);
}

.tool-card {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.tool-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.875rem 1rem;
    background: var(--bg-secondary);
    cursor: pointer;
}

.tool-title {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    font-weight: 500;
    font-size: 0.9rem;
}

.tool-title i {
    color: var(--accent-primary);
    width: 18px;
}

.tool-content {
    padding: 1rem;
    display: none;
}

.tool-card.active .tool-content {
    display: block;
}

/* Toggle Switch */
.toggle-switch {
    position: relative;
    width: 40px;
    height: 22px;
}

.toggle-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.toggle-slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-hover);
    border-radius: 22px;
    transition: var(--transition);
}

.toggle-slider:before {
    position: absolute;
    content: "";
    height: 16px;
    width: 16px;
    left: 3px;
    bottom: 3px;
    background: white;
    border-radius: 50%;
    transition: var(--transition);
}

.toggle-switch input:checked + .toggle-slider {
    background: var(--accent-primary);
}

.toggle-switch input:checked + .toggle-slider:before {
    transform: translateX(18px);
}

/* Form Groups */
.form-group {
    margin-bottom: 0.875rem;
}

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

.form-group label {
    display: block;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 0.375rem;
}

.form-group input[type="number"],
.form-group input[type="text"] {
    width: 100%;
    padding: 0.5rem 0.75rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-size: 0.875rem;
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent-primary);
}

.form-group input[type="range"] {
    width: 100%;
    accent-color: var(--accent-primary);
}

.form-group.small {
    flex: 1;
}

.form-group.small input {
    padding: 0.375rem 0.5rem;
    font-size: 0.8rem;
}

/* Preset Buttons */
.quality-presets,
.size-presets,
.aspect-presets {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.preset-btn {
    flex: 1;
    padding: 0.5rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 0.75rem;
    cursor: pointer;
    transition: var(--transition);
}

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

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

.preset-btn.small {
    padding: 0.375rem;
    font-size: 0.7rem;
}

/* Resize Mode */
.resize-mode {
    display: flex;
    background: var(--bg-secondary);
    border-radius: var(--radius-sm);
    padding: 3px;
    margin-bottom: 0.875rem;
}

.mode-btn {
    flex: 1;
    padding: 0.375rem;
    background: transparent;
    border: none;
    border-radius: 4px;
    color: var(--text-secondary);
    font-size: 0.75rem;
    cursor: pointer;
    transition: var(--transition);
}

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

.dimension-inputs {
    display: flex;
    align-items: flex-end;
    gap: 0.5rem;
}

.dimension-inputs .form-group {
    flex: 1;
    margin-bottom: 0;
}

.link-btn {
    width: 32px;
    height: 32px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.resize-percentage.hidden,
.resize-dimensions.hidden {
    display: none;
}

/* Crop Inputs */
.crop-inputs {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.input-row {
    display: flex;
    gap: 0.5rem;
}

/* Rotate/Flip Buttons */
.rotate-buttons,
.flip-buttons {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.flip-buttons {
    margin-bottom: 0;
}

.action-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.25rem;
    padding: 0.625rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 0.7rem;
    cursor: pointer;
    transition: var(--transition);
}

.action-btn i {
    font-size: 1rem;
}

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

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

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

.format-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 0.75rem 0.5rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
}

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

.format-btn.active {
    background: rgba(99, 102, 241, 0.15);
    border-color: var(--accent-primary);
}

.format-name {
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-primary);
}

.format-desc {
    font-size: 0.65rem;
    color: var(--text-muted);
    margin-top: 0.125rem;
}

/* Preview Panel */
.preview-panel {
    display: flex;
    flex-direction: column;
    background: var(--bg-card);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.preview-header {
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
}

.preview-tabs {
    display: flex;
    gap: 0.5rem;
}

.preview-tab {
    padding: 0.375rem 0.875rem;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.preview-tab:hover {
    border-color: var(--accent-primary);
}

.preview-tab.active {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: white;
}

.preview-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    background: repeating-conic-gradient(#1a1a2e 0% 25%, #12121a 0% 50%) 50% / 20px 20px;
    overflow: hidden;
    position: relative;
    min-height: 400px;
}

.preview-wrapper {
    position: relative;
    max-width: 100%;
    max-height: 100%;
}

.preview-wrapper img {
    max-width: 100%;
    max-height: 60vh;
    display: block;
    border-radius: var(--radius-sm);
}

.compare-slider {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
}

.compare-slider.hidden {
    display: none;
}

.compare-original,
.compare-edited {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.compare-original img,
.compare-edited img {
    max-width: 100%;
    max-height: 60vh;
    display: block;
}

.compare-handle {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 50%;
    width: 4px;
    background: var(--accent-primary);
    cursor: ew-resize;
    z-index: 10;
}

.handle-line {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 32px;
    height: 32px;
    background: var(--accent-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.handle-line::before {
    content: '⟷';
    color: white;
    font-size: 14px;
}

.preview-footer {
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: center;
}

.zoom-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.zoom-btn {
    width: 28px;
    height: 28px;
    background: var(--bg-hover);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

#zoomLevel {
    font-size: 0.8rem;
    color: var(--text-muted);
    min-width: 40px;
    text-align: center;
}

/* Crop Overlay */
.crop-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    pointer-events: none;
}

.crop-overlay.hidden {
    display: none;
}

.crop-box {
    position: absolute;
    border: 2px dashed var(--accent-primary);
    background: transparent;
    box-shadow: 0 0 0 9999px rgba(0, 0, 0, 0.5);
}

/* Info Panel */
.info-panel {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.info-card {
    background: var(--bg-card);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    padding: 1rem;
}

.info-card h3 {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.info-card h3 i {
    color: var(--accent-primary);
}

.info-grid {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.info-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.info-label {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.info-value {
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-primary);
}

.info-item.highlight .info-value {
    color: var(--success);
}

/* Operations List */
.operations-list {
    list-style: none;
    font-size: 0.8rem;
}

.operations-list li {
    padding: 0.375rem 0;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.operations-list li::before {
    content: "✓";
    color: var(--success);
    font-size: 0.7rem;
}

.operations-list li.empty-state::before {
    content: none;
}

.operations-list li.empty-state {
    color: var(--text-muted);
    font-style: italic;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-align: center;
}

.modal-content.loading {
    min-width: 200px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

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

/* Hidden utility */
.hidden {
    display: none !important;
}

/* Responsive */
@media (max-width: 1200px) {
    .editor-layout {
        grid-template-columns: 260px 1fr;
    }

    .info-panel {
        display: none;
    }
}

@media (max-width: 900px) {
    .editor-layout {
        grid-template-columns: 1fr;
    }

    .tools-panel {
        flex-direction: row;
        flex-wrap: wrap;
        max-height: none;
        overflow: visible;
    }

    .tool-card {
        flex: 1 1 200px;
        min-width: 200px;
    }

    .header h1 span {
        display: none;
    }
}

@media (max-width: 600px) {
    .header {
        padding: 0.75rem 1rem;
    }

    .header h1 {
        font-size: 1.1rem;
    }

    .btn span {
        display: none;
    }

    .upload-area {
        padding: 2rem 1rem;
    }

    .upload-icon {
        font-size: 3rem;
    }
}