/* CSS變數定義 */
:root {
    /* 亮色主題 */
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-secondary: #64748b;
    --color-success: #059669;
    --color-warning: #d97706;
    --color-danger: #dc2626;
    
    --color-bg: #ffffff;
    --color-surface: #f8fafc;
    --color-surface-hover: #f1f5f9;
    --color-border: #e2e8f0;
    --color-border-light: #f1f5f9;
    
    --color-text: #1e293b;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    
    --radius: 8px;
    --radius-sm: 4px;
    --radius-lg: 12px;
    
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, Inconsolata, 'Roboto Mono', monospace;
}

/* 深色主題 */
[data-color-scheme="dark"] {
    --color-bg: #0f172a;
    --color-surface: #1e293b;
    --color-surface-hover: #334155;
    --color-border: #334155;
    --color-border-light: #475569;
    
    --color-text: #f8fafc;
    --color-text-secondary: #cbd5e1;
    --color-text-muted: #94a3b8;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.4), 0 2px 4px -2px rgb(0 0 0 / 0.3);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.4), 0 4px 6px -4px rgb(0 0 0 / 0.3);
}

/* 基礎重置 */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

/* 容器佈局 */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 標題欄 */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid var(--color-border);
    margin-bottom: 20px;
}

.header h1 {
    font-size: 1.875rem;
    font-weight: 700;
    color: var(--color-text);
    margin: 0;
}

.header-controls {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* 標籤導覽 */
.tab-nav {
    display: flex;
    gap: 8px;
    margin-bottom: 32px;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 0;
}

.tab-btn {
    padding: 12px 24px;
    background: none;
    border: none;
    color: var(--color-text-secondary);
    font-weight: 500;
    cursor: pointer;
    border-radius: var(--radius) var(--radius) 0 0;
    transition: all 0.2s ease;
    position: relative;
    font-size: 1rem;
}

.tab-btn:hover {
    color: var(--color-text);
    background-color: var(--color-surface-hover);
}

.tab-btn.active {
    color: var(--color-primary);
    background-color: var(--color-surface);
    border-bottom: 2px solid var(--color-primary);
}

/* 主要內容 */
.main-content {
    flex: 1;
    margin-bottom: 40px;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.tool-section {
    background: var(--color-surface);
    border-radius: var(--radius-lg);
    padding: 32px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--color-border);
}

.tool-section h2 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--color-text);
}

.tool-description {
    color: var(--color-text-secondary);
    margin-bottom: 32px;
    font-size: 1rem;
    line-height: 1.6;
}

/* 處理模式 */
.processing-mode {
    margin-bottom: 32px;
}

.mode-toggle {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.mode-btn {
    padding: 8px 16px;
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    color: var(--color-text);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.875rem;
    font-weight: 500;
}

.mode-btn:hover {
    background: var(--color-surface-hover);
}

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

/* 分割方向控制 */
.direction-toggle {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.direction-btn {
    padding: 12px 20px;
    border: 1px solid var(--color-border);
    background: var(--color-bg);
    color: var(--color-text);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.9rem;
    font-weight: 500;
    flex: 1;
    text-align: center;
}

.direction-btn:hover {
    background: var(--color-surface-hover);
}

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

/* 上傳區域 */
.upload-section {
    margin-bottom: 32px;
}

.upload-buttons {
    display: flex;
    gap: 12px;
    margin-bottom: 16px;
}

.drop-zone {
    border: 2px dashed var(--color-border);
    border-radius: var(--radius-lg);
    padding: 48px 32px;
    text-align: center;
    background: var(--color-bg);
    transition: all 0.3s ease;
    cursor: pointer;
}

.drop-zone:hover {
    border-color: var(--color-primary);
    background: var(--color-surface);
}

.drop-zone.drag-over {
    border-color: var(--color-primary);
    background: var(--color-surface);
    transform: scale(1.02);
}

.drop-zone-content {
    pointer-events: none;
}

.drop-icon {
    font-size: 3rem;
    margin-bottom: 16px;
    opacity: 0.6;
}

.drop-zone p {
    font-size: 1.125rem;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 8px;
}

.drop-zone small {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
}

/* 檔案清單 */
.file-list {
    margin-top: 16px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-bg);
    max-height: 200px;
    overflow-y: auto;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    border-bottom: 1px solid var(--color-border-light);
}

.file-item:last-child {
    border-bottom: none;
}

.file-name {
    font-weight: 500;
    color: var(--color-text);
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-size {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    margin-left: 12px;
}

/* 控制項區域 */
.controls-section {
    margin-bottom: 32px;
    display: grid;
    gap: 24px;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-label {
    font-weight: 500;
    color: var(--color-text);
    font-size: 0.875rem;
    margin-bottom: 4px;
}

.form-control {
    padding: 10px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-bg);
    color: var(--color-text);
    font-size: 0.875rem;
    transition: all 0.2s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgb(37 99 235 / 0.1);
}

/* 滑桿樣式 */
.position-slider,
.quality-slider,
.threshold-slider {
    -webkit-appearance: none;
    appearance: none;
    height: 6px;
    background: var(--color-border);
    border-radius: 3px;
    outline: none;
    margin: 8px 0;
}

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

.position-slider::-webkit-slider-thumb:hover,
.quality-slider::-webkit-slider-thumb:hover,
.threshold-slider::-webkit-slider-thumb:hover {
    transform: scale(1.1);
}

.position-slider::-moz-range-thumb,
.quality-slider::-moz-range-thumb,
.threshold-slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: var(--color-primary);
    border-radius: 50%;
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-md);
}

/* 像素調整控制 */
.pixel-controls {
    background: var(--color-bg);
    border-radius: var(--radius-lg);
    padding: 24px;
    border: 1px solid var(--color-border);
}

.pixel-grid {
    display: grid;
    grid-template-columns: 1fr 200px 1fr;
    grid-template-rows: auto auto auto;
    gap: 20px;
    align-items: center;
    margin-bottom: 16px;
}

.pixel-control {
    text-align: center;
}

.pixel-control .form-label {
    margin-bottom: 8px;
    font-size: 0.8rem;
    font-weight: 600;
}

.pixel-input {
    width: 80px;
    text-align: center;
    margin: 0 auto;
    font-weight: 600;
}

.pixel-center {
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 12px;
    align-items: center;
}

.current-size {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text-secondary);
    padding: 8px 12px;
    background: var(--color-surface);
    border-radius: var(--radius);
    border: 1px solid var(--color-border);
    min-width: 100px;
}

.keyboard-hint {
    text-align: center;
    padding: 12px;
    background: var(--color-surface);
    border-radius: var(--radius);
    border: 1px solid var(--color-border);
}

/* 預覽區域 */
.preview-section {
    margin-bottom: 32px;
}

.preview-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.preview-header h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-text);
    margin: 0;
}

.zoom-controls {
    display: flex;
    gap: 8px;
}

.zoom-btn {
    padding: 6px 12px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    color: var(--color-text);
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.2s ease;
}

.zoom-btn:hover {
    background: var(--color-surface-hover);
}

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

.preview-container {
    position: relative;
    height: 400px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.preview-bg-light {
    background: #ffffff;
}

.preview-bg-dark {
    background: #374151;
}

.preview-bg-transparent {
    background-image: 
        linear-gradient(45deg, #f1f5f9 25%, transparent 25%),
        linear-gradient(-45deg, #f1f5f9 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, #f1f5f9 75%),
        linear-gradient(-45deg, transparent 75%, #f1f5f9 75%);
    background-size: 20px 20px;
    background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
}

.preview-canvas {
    max-width: 100%;
    max-height: 100%;
    cursor: grab;
    transition: transform 0.2s ease;
    transform-origin: center center;
}

.preview-canvas:active {
    cursor: grabbing;
}

.preview-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-surface);
    border-radius: var(--radius-lg);
}

.overlay-content {
    text-align: center;
    color: var(--color-text-secondary);
}

.upload-icon {
    font-size: 4rem;
    margin-bottom: 16px;
    opacity: 0.5;
}

.overlay-content p {
    font-size: 1.125rem;
    font-weight: 500;
}

/* 動作區域 */
.action-section {
    margin-top: 32px;
}

/* 進度條 */
.progress-container {
    margin-top: 16px;
    text-align: center;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--color-border);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-fill {
    height: 100%;
    background: var(--color-primary);
    width: 0%;
    transition: width 0.3s ease;
    border-radius: 4px;
}

.progress-text {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
}

/* 按鈕樣式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 20px;
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    font-size: 0.875rem;
    line-height: 1;
    gap: 8px;
}

.btn:hover {
    background: var(--color-primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

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

.btn--outline:hover {
    background: var(--color-surface-hover);
    color: var(--color-text);
    transform: translateY(-1px);
}

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

.btn--secondary:hover {
    background: #475569;
}

.btn--sm {
    padding: 6px 12px;
    font-size: 0.8rem;
}

.btn--lg {
    padding: 16px 32px;
    font-size: 1rem;
    font-weight: 600;
}

.btn--full-width {
    width: 100%;
}

/* 頁腳 */
.footer {
    text-align: center;
    padding: 24px 0;
    color: var(--color-text-secondary);
    border-top: 1px solid var(--color-border);
    margin-top: auto;
    font-size: 0.875rem;
}

/* 響應式設計 */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .header {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
    
    .header h1 {
        font-size: 1.5rem;
    }
    
    .tab-nav {
        flex-wrap: wrap;
        gap: 4px;
    }
    
    .tab-btn {
        padding: 10px 16px;
        font-size: 0.875rem;
    }
    
    .tool-section {
        padding: 24px 20px;
    }
    
    .upload-buttons {
        flex-direction: column;
    }
    
    .drop-zone {
        padding: 32px 20px;
    }
    
    .drop-icon {
        font-size: 2.5rem;
    }
    
    .pixel-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .direction-toggle {
        flex-direction: column;
    }
    
    .zoom-controls {
        flex-wrap: wrap;
        gap: 4px;
    }
    
    .zoom-btn {
        padding: 4px 8px;
        font-size: 0.75rem;
    }
    
    .preview-container {
        height: 300px;
    }
    
    .controls-section {
        gap: 16px;
    }
}

@media (max-width: 480px) {
    .drop-zone {
        padding: 24px 16px;
    }
    
    .drop-icon {
        font-size: 2rem;
    }
    
    .drop-zone p {
        font-size: 1rem;
    }
    
    .preview-container {
        height: 250px;
    }
    
    .tool-section {
        padding: 20px 16px;
    }
    
    .zoom-controls {
        display: none;
    }
}

/* 動畫效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* 滾動條樣式 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-surface);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-text-muted);
}

/* 高對比度和可訪問性 */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* 焦點樣式 */
.btn:focus,
.form-control:focus,
.tab-btn:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* 選擇狀態 */
::selection {
    background: var(--color-primary);
    color: white;
}

/* 載入狀態 */
.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

.btn:disabled:hover {
    background: var(--color-primary);
    transform: none;
    box-shadow: none;
}