/* ================================================
   绣花图案转换器 - 专业UI设计系统 v3.0
   ================================================ */

/* === 设计令牌 (Design Tokens) === */
:root {
    /* 品牌色 */
    --primary-50: #eef2ff;
    --primary-100: #e0e7ff;
    --primary-200: #c7d2fe;
    --primary-300: #a5b4fc;
    --primary-400: #818cf8;
    --primary-500: #6366f1;
    --primary-600: #4f46e5;
    --primary-700: #4338ca;
    
    /* 中性色 */
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* 功能色 */
    --success-500: #10b981;
    --success-600: #059669;
    --warning-500: #f59e0b;
    --warning-600: #d97706;
    --error-500: #ef4444;
    --error-600: #dc2626;
    
    /* 间距系统 (4px base) */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-8: 32px;
    --space-10: 40px;
    --space-12: 48px;
    
    /* 圆角 */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;
    
    /* 阴影 */
    --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);
    --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.15);
    
    /* 动画 */
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
    --duration-fast: 150ms;
    --duration-normal: 250ms;
    --duration-slow: 400ms;
}

/* === 基础重置 === */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #1e1b4b 0%, #312e81 50%, #4c1d95 100%);
    background-attachment: fixed;
    min-height: 100vh;
    color: var(--gray-800);
    line-height: 1.6;
}

/* 背景装饰 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(ellipse at 20% 20%, rgba(139, 92, 246, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 80%, rgba(59, 130, 246, 0.1) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 50%, rgba(236, 72, 153, 0.05) 0%, transparent 70%);
    pointer-events: none;
    z-index: -1;
}

.container {
    min-height: 100vh;
    padding: var(--space-5);
}

/* === 登录页面 === */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: var(--space-5);
}

.login-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    padding: var(--space-10);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl), var(--shadow-glow);
    width: 100%;
    max-width: 420px;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.login-card h1 {
    text-align: center;
    margin-bottom: var(--space-8);
    font-size: 1.75rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-600), var(--primary-500));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* === 表单组件 === */
.form-group {
    margin-bottom: var(--space-5);
}

.form-group label {
    display: block;
    margin-bottom: var(--space-2);
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--gray-700);
    letter-spacing: -0.01em;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-size: 0.9375rem;
    color: var(--gray-800);
    background: white;
    transition: all var(--duration-fast) var(--ease-out);
}

.form-group input:hover,
.form-group select:hover {
    border-color: var(--gray-300);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-500);
    box-shadow: 0 0 0 4px var(--primary-100);
}

.form-group input::placeholder {
    color: var(--gray-400);
}

/* 选项说明 */
.option-description {
    display: flex;
    align-items: flex-start;
    gap: var(--space-2);
    margin-top: var(--space-2);
    padding: var(--space-2) var(--space-3);
    background: var(--gray-50);
    border-radius: var(--radius-sm);
    border-left: 2px solid var(--primary-300);
}

.option-description .desc-icon {
    font-size: 0.875rem;
    flex-shrink: 0;
    opacity: 0.8;
}

.option-description .desc-text {
    font-size: 0.75rem;
    color: var(--gray-500);
    line-height: 1.5;
}

.error-message {
    background: linear-gradient(135deg, #fef2f2, #fee2e2);
    color: var(--error-600);
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-md);
    margin-bottom: var(--space-5);
    text-align: center;
    font-size: 0.875rem;
    font-weight: 500;
    border: 1px solid rgba(239, 68, 68, 0.2);
}

/* === 主页面布局 === */
.main-container {
    max-width: 1440px;
    margin: 0 auto;
}

/* 顶部导航 */
header {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-5);
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-md);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

header h1 {
    font-size: 1.375rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-600), #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

header h1::before {
    content: '🧵';
    font-size: 1.5rem;
    -webkit-text-fill-color: initial;
}

.logout-link {
    color: var(--gray-500);
    text-decoration: none;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    transition: all var(--duration-fast) var(--ease-out);
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.logout-link::before {
    content: '👋';
}

.logout-link:hover {
    background: var(--gray-100);
    color: var(--gray-700);
}

/* === 内容布局 V2 === */
.content-wrapper-v2 {
    display: flex;
    flex-direction: column;
    gap: var(--space-5);
}

.top-panel {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-5);
}

@media (max-width: 960px) {
    .top-panel {
        grid-template-columns: 1fr;
    }
}

/* === 卡片组件 === */
.card {
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(20px);
    padding: var(--space-6);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    border: 1px solid rgba(255, 255, 255, 0.3);
    transition: all var(--duration-normal) var(--ease-out);
}

.card:hover {
    box-shadow: var(--shadow-xl);
}

.card h2 {
    margin-bottom: var(--space-5);
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--gray-800);
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

/* === 上传区域 === */
.upload-area {
    border: 2px dashed var(--gray-300);
    border-radius: var(--radius-lg);
    padding: var(--space-10) var(--space-6);
    text-align: center;
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    background: linear-gradient(135deg, var(--gray-50), white);
    position: relative;
    overflow: hidden;
}

.upload-area::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, var(--primary-100), var(--primary-50));
    opacity: 0;
    transition: opacity var(--duration-normal) var(--ease-out);
}

.upload-area:hover {
    border-color: var(--primary-400);
    transform: translateY(-2px);
}

.upload-area:hover::before {
    opacity: 1;
}

.upload-area.dragover {
    border-color: var(--primary-500);
    border-style: solid;
    transform: scale(1.02);
}

.upload-area.dragover::before {
    opacity: 1;
}

.upload-placeholder {
    position: relative;
    z-index: 1;
}

.upload-placeholder svg {
    color: var(--gray-400);
    margin-bottom: var(--space-4);
    transition: all var(--duration-normal) var(--ease-out);
}

.upload-area:hover .upload-placeholder svg {
    color: var(--primary-500);
    transform: translateY(-4px);
}

.upload-placeholder p {
    margin: var(--space-2) 0;
    color: var(--gray-600);
    font-weight: 500;
}

.upload-hint {
    font-size: 0.8125rem;
    color: var(--gray-400);
}

/* 文件信息 */
.file-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-3) var(--space-4);
    background: linear-gradient(135deg, var(--primary-50), white);
    border-radius: var(--radius-md);
    margin-top: var(--space-4);
    border: 1px solid var(--primary-100);
}

.file-preview {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

#fileName {
    font-weight: 600;
    color: var(--gray-800);
    font-size: 0.875rem;
}

.image-info {
    font-size: 0.75rem;
    color: var(--gray-500);
    background: var(--gray-100);
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-sm);
    font-weight: 500;
}

/* 智能提示 */
.smart-tip {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    margin-top: var(--space-4);
    padding: var(--space-4);
    background: linear-gradient(135deg, #fef9c3 0%, #fef3c7 100%);
    border-radius: var(--radius-md);
    border: 1px solid rgba(245, 158, 11, 0.2);
    animation: slideIn var(--duration-slow) var(--ease-out);
}

@keyframes slideIn {
    from { 
        opacity: 0; 
        transform: translateY(-12px); 
    }
    to { 
        opacity: 1; 
        transform: translateY(0); 
    }
}

.smart-tip .tip-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.smart-tip .tip-content {
    flex: 1;
}

.smart-tip .tip-title {
    font-weight: 700;
    color: var(--warning-600);
    font-size: 0.9375rem;
    margin-bottom: var(--space-1);
}

.smart-tip .tip-text {
    font-size: 0.8125rem;
    color: #92400e;
    line-height: 1.6;
}

/* === 按钮系统 === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.9375rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--duration-fast) var(--ease-out);
    text-decoration: none;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-600), var(--primary-500));
    color: white;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.25);
}

.btn-primary:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--primary-700), var(--primary-600));
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.35);
}

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

.btn-primary:disabled {
    background: var(--gray-300);
    box-shadow: none;
    cursor: not-allowed;
    opacity: 0.7;
}

.btn-success {
    background: linear-gradient(135deg, var(--success-600), var(--success-500));
    color: white;
    box-shadow: 0 2px 8px rgba(16, 185, 129, 0.25);
}

.btn-success:hover {
    background: linear-gradient(135deg, #047857, var(--success-600));
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(16, 185, 129, 0.35);
}

.btn-danger {
    background: linear-gradient(135deg, var(--error-600), var(--error-500));
    color: white;
}

.btn-danger:hover {
    background: linear-gradient(135deg, #b91c1c, var(--error-600));
}

.btn-block {
    width: 100%;
}

.btn-small {
    padding: var(--space-2) var(--space-3);
    font-size: 0.8125rem;
}

/* === 对比预览区域 === */
.comparison-card {
    min-height: 450px;
}

.comparison-area {
    display: flex;
    flex-direction: column;
    gap: var(--space-5);
}

.comparison-area .empty-state {
    padding: var(--space-12) var(--space-5);
    text-align: center;
    color: var(--gray-400);
    font-size: 0.9375rem;
}

.comparison-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-5);
}

@media (max-width: 800px) {
    .comparison-grid {
        grid-template-columns: 1fr;
    }
}

.comparison-item {
    background: var(--gray-50);
    border-radius: var(--radius-lg);
    padding: var(--space-5);
    text-align: center;
    transition: all var(--duration-normal) var(--ease-out);
}

.comparison-item h4 {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--gray-600);
    margin-bottom: var(--space-4);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
}

.comparison-item .image-wrapper {
    background: white;
    border-radius: var(--radius-md);
    padding: var(--space-4);
    box-shadow: var(--shadow-sm);
    cursor: zoom-in;
    position: relative;
    overflow: hidden;
    transition: all var(--duration-normal) var(--ease-out);
    border: 1px solid var(--gray-100);
}

.comparison-item .image-wrapper:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
    border-color: var(--primary-200);
}

.comparison-item .image-wrapper img {
    max-width: 100%;
    max-height: 380px;
    object-fit: contain;
    display: block;
    margin: 0 auto;
    border-radius: var(--radius-sm);
}

.comparison-item .image-wrapper::after {
    content: '🔍 点击放大';
    position: absolute;
    bottom: var(--space-3);
    right: var(--space-3);
    background: rgba(0, 0, 0, 0.75);
    color: white;
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-full);
    font-size: 0.6875rem;
    font-weight: 500;
    opacity: 0;
    transform: translateY(4px);
    transition: all var(--duration-fast) var(--ease-out);
}

.comparison-item .image-wrapper:hover::after {
    opacity: 1;
    transform: translateY(0);
}

/* 统计徽章 */
.result-stats-inline {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-3);
    justify-content: center;
    padding-top: var(--space-5);
    border-top: 1px solid var(--gray-200);
}

.stat-badge {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    background: white;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-full);
    font-size: 0.8125rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--gray-100);
    transition: all var(--duration-fast) var(--ease-out);
}

.stat-badge:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.stat-badge .stat-label {
    color: var(--gray-500);
}

.stat-badge .stat-value {
    font-weight: 700;
    color: var(--primary-600);
}

/* 下载按钮组 */
.download-buttons-inline {
    display: flex;
    gap: var(--space-3);
    justify-content: center;
    margin-top: var(--space-5);
}

/* 加载状态 */
.loading-overlay {
    position: absolute;
    inset: 0;
    background: rgba(255, 255, 255, 0.95);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    backdrop-filter: blur(4px);
}

.loading-overlay .spinner,
.spinner {
    width: 44px;
    height: 44px;
    border: 3px solid var(--gray-200);
    border-top-color: var(--primary-500);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.loading-overlay p {
    margin-top: var(--space-4);
    color: var(--gray-600);
    font-size: 0.875rem;
    font-weight: 500;
}

/* === 图片查看器 === */
.image-viewer-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.96);
    z-index: 10000;
    display: none;
    opacity: 0;
    transition: opacity var(--duration-normal) var(--ease-out);
}

.image-viewer-overlay.active {
    display: flex;
    flex-direction: column;
}

.image-viewer-overlay.visible {
    opacity: 1;
}

.image-viewer-container {
    display: flex;
    flex-direction: column;
    width: 100%;
    height: 100%;
}

.image-viewer-toolbar {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    background: rgba(20, 20, 20, 0.95);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.viewer-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border: none;
    border-radius: var(--radius-md);
    background: rgba(255, 255, 255, 0.08);
    color: white;
    cursor: pointer;
    transition: all var(--duration-fast) var(--ease-out);
}

.viewer-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: scale(1.05);
}

.viewer-btn:active {
    transform: scale(0.95);
}

.viewer-btn.viewer-close {
    background: rgba(239, 68, 68, 0.2);
    margin-left: var(--space-5);
}

.viewer-btn.viewer-close:hover {
    background: rgba(239, 68, 68, 0.4);
}

.zoom-level {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.875rem;
    font-weight: 600;
    min-width: 65px;
    text-align: center;
    margin-right: var(--space-2);
    font-variant-numeric: tabular-nums;
}

.image-viewer-content {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    cursor: grab;
    position: relative;
}

.image-viewer-content:active {
    cursor: grabbing;
}

.image-viewer-content img {
    max-width: none;
    max-height: none;
    transition: transform 0.1s ease-out;
    user-select: none;
    -webkit-user-drag: none;
}

.image-viewer-hint {
    text-align: center;
    padding: var(--space-3);
    color: rgba(255, 255, 255, 0.4);
    font-size: 0.75rem;
    background: rgba(20, 20, 20, 0.95);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    letter-spacing: 0.05em;
}

/* === 响应式优化 === */
@media (max-width: 768px) {
    :root {
        --space-5: 16px;
        --space-6: 20px;
    }
    
    .container {
        padding: var(--space-3);
    }

    header {
        padding: var(--space-3) var(--space-4);
        border-radius: var(--radius-md);
    }

    header h1 {
        font-size: 1.125rem;
    }

    .card {
        padding: var(--space-5);
        border-radius: var(--radius-md);
    }

    .upload-area {
        padding: var(--space-8) var(--space-4);
    }
    
    .comparison-item .image-wrapper img {
        max-height: 280px;
    }
    
    .download-buttons-inline {
        flex-direction: column;
    }
    
    .download-buttons-inline .btn {
        width: 100%;
    }
}

/* === 深色模式提示（可选） === */
@media (prefers-color-scheme: dark) {
    /* 保持亮色主题，背景已经是深色 */
}

/* === 打印样式 === */
@media print {
    body {
        background: white;
    }
    
    header, .upload-card, .params-card, .smart-tip {
        display: none;
    }
    
    .comparison-card {
        box-shadow: none;
        border: 1px solid #ddd;
    }
}

/* === 滑块样式 === */
.range-slider {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: var(--gray-200);
    outline: none;
    transition: all var(--duration-fast) var(--ease-out);
}

.range-slider:hover {
    background: var(--gray-300);
}

.range-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.3);
    transition: all var(--duration-fast) var(--ease-out);
}

.range-slider::-webkit-slider-thumb:hover {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.range-slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-500), var(--primary-600));
    cursor: pointer;
    border: none;
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.3);
}

.range-value {
    text-align: center;
    margin-top: var(--space-2);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--primary-600);
}