/* ChatGPT和Apple风格的CSS样式 */
:root {
    /* Apple风格颜色系统 */
    --primary-color: #007AFF;
    --primary-hover: #0056CC;
    --secondary-color: #34C759;
    --warning-color: #FF9500;
    --danger-color: #FF3B30;
    --text-primary: #1D1D1F;
    --text-secondary: #86868B;
    --background-primary: #FFFFFF;
    --background-secondary: #F5F5F7;
    --background-tertiary: #FAFAFA;
    --border-color: #E5E5E7;
    --border-hover: #C7C7CC;
    --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 16px rgba(0, 0, 0, 0.12);
    --shadow-heavy: 0 8px 32px rgba(0, 0, 0, 0.16);
    --radius-small: 8px;
    --radius-medium: 12px;
    --radius-large: 16px;
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    background: var(--background-secondary);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

/* 应用容器 */
.app-container {
    min-height: 100vh;
    display: flex;
    max-width: 1400px;
    margin: 0 auto;
    background: var(--background-primary);
    gap: var(--spacing-lg);
}

/* 主要内容包装器 */
.main-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* 广告侧边栏 */
.ad-sidebar {
    width: 160px;
    background: var(--background-secondary);
    border-radius: var(--radius-large);
    padding: var(--spacing-md);
    height: fit-content;
    position: sticky;
    top: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.ad-sidebar-left {
    order: -1;
}

.ad-sidebar-right {
    order: 1;
}

.ad-container {
    position: relative;
}

.ad-placeholder {
    background: var(--background-tertiary);
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-medium);
    height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    font-size: 14px;
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.adsbygoogle {
    display: block !important;
    width: 100%;
    min-height: 250px;
}

/* 导航栏 - ChatGPT风格 */
.nav-bar {
    background: var(--background-primary);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-content {
    padding: var(--spacing-md) var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-title {
    font-size: 24px;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}

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

.language-selector {
    padding: var(--spacing-xs) var(--spacing-sm);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-small);
    background: var(--background-tertiary);
    font-size: 14px;
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.language-selector:hover {
    border-color: var(--border-hover);
}

.language-selector:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.1);
}

/* 主内容区 */
.main-content {
    flex: 1;
    padding: var(--spacing-xl);
    display: flex;
    justify-content: center;
    align-items: flex-start;
}

.signature-card {
    width: 100%;
    max-width: 800px;
    background: var(--background-primary);
    border-radius: var(--radius-large);
    box-shadow: var(--shadow-medium);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

/* 提示区域 */
.prompt-section {
    padding: var(--spacing-xl);
    background: var(--background-tertiary);
    border-bottom: 1px solid var(--border-color);
    text-align: center;
}

.prompt-title {
    font-size: 18px;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
}

.action-buttons {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
}

/* 按钮样式 - Apple风格 */
.btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: var(--radius-small);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 36px;
    text-decoration: none;
    user-select: none;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 122, 255, 0.3);
}

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

.btn-secondary:hover {
    background: var(--background-secondary);
    border-color: var(--border-hover);
    transform: translateY(-1px);
}

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

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

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

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

/* 画布容器 */
.canvas-container {
    position: relative;
    padding: var(--spacing-xl);
    background: white;
    min-height: 400px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.signature-canvas {
    border: 2px solid var(--border-color);
    border-radius: var(--radius-medium);
    background: white;
    cursor: crosshair;
    transition: border-color 0.2s ease;
    box-shadow: var(--shadow-light);
    width: 100%;
    max-width: 700px;
    height: 300px;
}

.signature-canvas:hover {
    border-color: var(--primary-color);
}

.canvas-placeholder {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: var(--text-secondary);
    font-size: 16px;
    pointer-events: none;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.canvas-container.empty .canvas-placeholder {
    opacity: 1;
}

/* 工具栏 */
.toolbar {
    padding: var(--spacing-xl);
    background: var(--background-tertiary);
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xl);
    justify-content: space-between;
}

.tool-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    min-width: 120px;
}

.tool-label {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

/* 颜色选择器 */
.color-palette {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

.color-swatch {
    width: 32px;
    height: 32px;
    border-radius: var(--radius-small);
    cursor: pointer;
    border: 2px solid transparent;
    transition: all 0.2s ease;
    position: relative;
}

.color-swatch:hover {
    transform: scale(1.1);
    box-shadow: var(--shadow-light);
}

.color-swatch.active {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(0, 122, 255, 0.2);
}

.color-swatch::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 6px;
    background: currentColor;
}

.color-swatch[data-color="#000000"]::after { background: #000000; }
.color-swatch[data-color="#FF0000"]::after { background: #FF0000; }
.color-swatch[data-color="#0066FF"]::after { background: #0066FF; }
.color-swatch[data-color="#00AA00"]::after { background: #00AA00; }
.color-swatch[data-color="#8A2BE2"]::after { background: #8A2BE2; }

.custom-color-picker {
    width: 32px;
    height: 32px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-small);
    cursor: pointer;
    background: none;
}

.custom-color-picker::-webkit-color-swatch {
    border: none;
    border-radius: 4px;
}

/* 粗细控制 */
.thickness-control {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.thickness-slider {
    flex: 1;
    height: 6px;
    border-radius: 3px;
    background: var(--border-color);
    outline: none;
    appearance: none;
    cursor: pointer;
}

.thickness-slider::-webkit-slider-thumb {
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: 2px solid white;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.thickness-slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: 2px solid white;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.thickness-value {
    min-width: 20px;
    text-align: center;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.thickness-preview {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--text-primary);
    transition: all 0.2s ease;
}

/* 导出选项 */
.export-options {
    display: flex;
    gap: var(--spacing-sm);
}

/* 底部 */
.footer {
    padding: var(--spacing-lg);
    text-align: center;
    border-top: 1px solid var(--border-color);
    background: var(--background-tertiary);
}

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

/* SEO 静态内容区 */
.seo-section {
    padding: var(--spacing-xl) var(--spacing-xl) var(--spacing-xxl, 48px);
    background: var(--background-primary);
}
.seo-container {
    max-width: 800px;
    margin: 0 auto;
    color: var(--text-primary);
}
.seo-container h2 {
    font-size: 22px;
    margin-bottom: var(--spacing-md);
}
.seo-container h3 {
    font-size: 18px;
    margin: var(--spacing-lg) 0 var(--spacing-sm);
}
.seo-container p {
    margin: var(--spacing-sm) 0;
    color: var(--text-primary);
}
.seo-container ul {
    margin-left: 1.25rem;
    color: var(--text-primary);
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .ad-sidebar {
        display: none;
    }

    .app-container {
        max-width: 800px;
    }
}

@media (max-width: 768px) {
    .nav-content {
        padding: var(--spacing-md);
    }

    .nav-title {
        font-size: 20px;
    }

    .main-content {
        padding: var(--spacing-md);
    }

    .prompt-section {
        padding: var(--spacing-lg);
    }

    .action-buttons {
        flex-direction: column;
        align-items: center;
    }

    .canvas-container {
        padding: var(--spacing-md);
    }

    .signature-canvas {
        height: 250px;
    }

    .toolbar {
        flex-direction: column;
        gap: var(--spacing-lg);
    }

    .tool-group {
        min-width: auto;
    }

    .export-options {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .nav-title {
        font-size: 18px;
    }

    .signature-canvas {
        height: 200px;
    }

    .color-palette {
        flex-wrap: wrap;
    }

    .thickness-control {
        flex-direction: column;
        align-items: stretch;
    }
}

/* 暗色模式支持 */
@media (prefers-color-scheme: dark) {
    :root {
        --text-primary: #F2F2F7;
        --text-secondary: #8E8E93;
        --background-primary: #1C1C1E;
        --background-secondary: #2C2C2E;
        --background-tertiary: #3A3A3C;
        --border-color: #38383A;
        --border-hover: #48484A;
    }

    .signature-canvas {
        background: var(--background-primary);
        border-color: var(--border-color);
    }
}

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

.signature-card {
    animation: fadeIn 0.6s ease-out;
}

/* 加载状态 */
.loading {
    position: relative;
    overflow: hidden;
}

.loading::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transform: translateX(-100%);
    animation: loading 1.5s infinite;
}

@keyframes loading {
    100% {
        transform: translateX(100%);
    }
}