/* ===========================================
   AI Tools Tutorial - CSS Styles
   极简暗黑科技风设计 (Linear/Vercel Style)
   =========================================== */

/* CSS Variables - Light Mode (Default) */
:root {
    /* Colors - Light Mode */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-card: rgba(255, 255, 255, 0.95);
    --bg-code: #1e1e1e;
    --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);

    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --text-tertiary: #94a3b8;
    --text-inverse: #ffffff;

    --accent-primary: #6366f1;
    --accent-primary-hover: #4f46e5;
    --accent-secondary: #06b6d4;
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --accent-error: #ef4444;

    --border-primary: #e2e8f0;
    --border-secondary: #f1f5f9;
    --border-glow: rgba(99, 102, 241, 0.3);

    /* Shadows - Enhanced */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.12);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);
    --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.4);
    --shadow-card: 0 8px 24px rgba(0, 0, 0, 0.08);

    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 24px;
    --spacing-2xl: 32px;
    --spacing-3xl: 48px;

    /* Border Radius - More rounded */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 24px;
    --radius-full: 9999px;

    /* Typography */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

    /* Transitions - Smoother */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Backdrop */
    --backdrop-blur: blur(12px);
}

/* 性能优化：减少动画对低端设备的影响 */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* GPU 加速提示：仅在即将或正在动画时启用 will-change
   避免永久性合成层占用内存 */

/* step-card: hover 时上浮，父容器悬停时提前提示浏览器 */
.product-content:hover .step-card:hover,
.step-card:hover {
    will-change: transform;
}

/* product-tab: hover / active 时有 transform 动画 */
.product-tabs:hover .product-tab,
.product-tab:hover,
.product-tab.active {
    will-change: transform;
}

/* modal-content: 仅在打开时做弹性缩放动画 */
.modal-overlay.active .modal-content {
    will-change: transform, opacity;
}

/* toast: 仅在显示时做位移动画 */
.toast.active {
    will-change: transform, opacity;
}

/* faq-arrow: 仅在展开态有旋转 */
.faq-item.open .faq-arrow,
.faq-item:hover .faq-arrow {
    will-change: transform;
}

/* Dark Mode - Enhanced Tech Style */
[data-theme="dark"] {
    --bg-primary: #0a0a0f;
    --bg-secondary: #0f0f1a;
    --bg-card: rgba(23, 23, 35, 0.95);
    --bg-code: #0d0d15;
    --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);

    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-tertiary: #64748b;
    --text-inverse: #0a0a0f;

    --accent-primary: #818cf8;
    --accent-primary-hover: #a5b4fc;
    --accent-secondary: #22d3ee;
    --accent-success: #34d399;
    --accent-warning: #fbbf24;
    --accent-error: #f87171;

    --border-primary: #1e293b;
    --border-secondary: #1a1f2e;
    --border-glow: rgba(129, 140, 248, 0.4);

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.5);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.6);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.7);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.8);
    --shadow-glow: 0 0 20px rgba(129, 140, 248, 0.5);
    --shadow-card: 0 8px 24px rgba(0, 0, 0, 0.6);
}

/* ===========================================
   Base Styles
   =========================================== */

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

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

body {
    font-family: var(--font-sans);
    font-size: 15px;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-secondary);
    min-height: 100vh;
    transition: background var(--transition-base), color var(--transition-base);
    position: relative;
    overflow-x: hidden;
}

/* Subtle background pattern for tech feel */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.03) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(6, 182, 212, 0.03) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

a {
    color: var(--accent-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--accent-primary-hover);
    text-decoration: underline;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

img {
    max-width: 100%;
    height: auto;
}

code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background: var(--bg-code);
    color: #e5e7eb;
    padding: 2px 6px;
    border-radius: var(--radius-sm);
}

/* ===========================================
   Header
   =========================================== */

.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.85);
    border-bottom: 1px solid var(--border-primary);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    transition: all var(--transition-base);
}

[data-theme="dark"] .header {
    background: rgba(10, 10, 15, 0.85);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3), 0 0 20px rgba(99, 102, 241, 0.05);
}

.header-content {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

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

.logo-icon {
    font-size: 28px;
}

.logo h1 {
    font-size: 26px;
    font-weight: 700;
    color: var(--text-primary);
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Theme Switcher */
.theme-switcher {
    display: flex;
    background: var(--bg-secondary);
    border-radius: var(--radius-full);
    padding: 4px;
    gap: 2px;
    border: 1px solid var(--border-primary);
}

.theme-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    color: var(--text-tertiary);
    transition: all var(--transition-fast);
}

.theme-btn:hover {
    color: var(--text-secondary);
    background: var(--bg-card);
    transform: scale(1.05);
}

.theme-btn.active {
    color: var(--accent-primary);
    background: var(--bg-card);
    box-shadow: var(--shadow-sm), 0 0 10px rgba(99, 102, 241, 0.2);
}

/* ===========================================
   Support Bar
   =========================================== */

.support-bar {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #06b6d4 100%);
    background-size: 200% 200%;
    animation: gradientShift 12s ease infinite;
    color: white;
    position: relative;
    overflow: hidden;
}

.support-bar::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 200%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.08), transparent);
    animation: shimmer 4s ease-in-out infinite;
    will-change: transform;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

@keyframes shimmer {
    0% { transform: translate3d(-50%, 0, 0); }
    100% { transform: translate3d(50%, 0, 0); }
}

.support-content {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-xl);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-lg);
}

.support-text {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 14px;
    font-weight: 500;
}

.support-icon {
    font-size: 18px;
}

.support-qr {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    cursor: pointer;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    transition: background var(--transition-fast);
}

.support-qr:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: scale(1.02);
}

.qr-thumbnail {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    border: 2px solid rgba(255, 255, 255, 0.4);
    object-fit: cover;
    transition: all var(--transition-fast);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.support-qr:hover .qr-thumbnail {
    border-color: rgba(255, 255, 255, 0.8);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.qr-hint {
    font-size: 12px;
    opacity: 0.9;
}

/* ===========================================
   Main Container
   =========================================== */

.main-container {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-xl);
}

/* ===========================================
   Product Tabs (Primary)
   =========================================== */

.product-tabs {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
}

.product-tab {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 10px 16px;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-secondary);
    background: var(--bg-card);
    border: 2px solid var(--border-primary);
    border-radius: var(--radius-lg);
    transition: color var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast), background var(--transition-fast);
    position: relative;
    overflow: visible;
    cursor: pointer;
}

.product-tab:hover {
    color: var(--text-primary);
    border-color: var(--accent-primary);
    transform: translate3d(0, -2px, 0);
    box-shadow: var(--shadow-md);
}

.product-tab.active {
    color: white;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-color: transparent;
    box-shadow: var(--shadow-glow), 0 4px 15px rgba(99, 102, 241, 0.4);
    transform: translate3d(0, -2px, 0);
}

.product-tab.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 0;
    border-left: 8px solid transparent;
    border-right: 8px solid transparent;
    border-top: 8px solid var(--accent-primary);
    z-index: 2;
}

.tab-icon {
    font-size: 18px;
    transition: transform var(--transition-fast);
}

.product-tab:hover .tab-icon {
    transform: scale(1.1);
}

.product-tab.active .tab-icon {
    transform: scale(1.15);
    filter: drop-shadow(0 0 4px rgba(255, 255, 255, 0.5));
}

/* ===========================================
   Platform Tabs (Secondary)
   =========================================== */

.platform-tabs {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-xl);
    background: var(--bg-card);
    padding: var(--spacing-xs);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-primary);
}

.platform-tab {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.platform-tab:hover {
    color: var(--text-primary);
    background: var(--bg-secondary);
}

.platform-tab.active {
    color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.1);
    font-weight: 600;
}

.platform-tab svg {
    width: 18px;
    height: 18px;
    transition: transform var(--transition-fast);
}

.platform-tab:hover svg {
    transform: scale(1.1);
}

/* ===========================================
   Content Area
   =========================================== */

.content-area {
    min-height: 400px;
}

.product-content {
    display: none;
}

.product-content.active {
    display: block;
    animation: fadeIn var(--transition-base) forwards;
}

.platform-content {
    display: none;
}

.platform-content.active {
    display: block;
    animation: fadeIn var(--transition-base) forwards;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translate3d(0, 8px, 0);
    }
    to {
        opacity: 1;
        transform: translate3d(0, 0, 0);
    }
}

/* ===========================================
   Step Cards
   =========================================== */

.step-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
    position: relative;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.step-card:hover {
    transform: translate3d(0, -4px, 0);
    box-shadow: var(--shadow-card);
    border-color: var(--border-glow);
}

.step-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.step-card:hover::after {
    opacity: 1;
}

.step-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
}

.step-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    font-size: 14px;
    font-weight: 700;
    border-radius: var(--radius-full);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.step-content {
    color: var(--text-secondary);
}

.step-content p {
    margin-bottom: var(--spacing-md);
}

.step-image {
    margin: var(--spacing-md) 0;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--border-primary);
    box-shadow: var(--shadow-sm);
    max-width: 100%;
}

.step-image img {
    display: block;
    width: 100%;
    height: auto;
}

.step-content h4 {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    margin: var(--spacing-lg) 0 var(--spacing-sm);
}

.step-content h4:first-child {
    margin-top: 0;
}

.step-content ol, .step-content ul {
    margin-left: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
}

.step-content li {
    margin-bottom: var(--spacing-sm);
}

/* ===========================================
   Code Blocks
   =========================================== */

.code-block {
    position: relative;
    margin: var(--spacing-md) 0;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid rgba(99, 102, 241, 0.2);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.code-block code {
    display: block;
    padding: var(--spacing-lg);
    background: linear-gradient(180deg, #1a1a2e 0%, #16161a 100%);
    color: #e2e8f0;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.7;
    overflow-x: auto;
    border-radius: var(--radius-lg);
}

.code-block::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    opacity: 0.8;
}

.code-block::after {
    content: 'Copy';
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: 12px;
    font-weight: 600;
    color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.15);
    border: 1px solid rgba(99, 102, 241, 0.3);
    border-radius: var(--radius-md);
    cursor: pointer;
    opacity: 0;
    transition: all var(--transition-fast);
}

.code-block:hover::after {
    opacity: 1;
}

.code-block::after:hover {
    background: rgba(99, 102, 241, 0.25);
}

.code-block.copied::after {
    content: 'Copied!';
    color: var(--accent-success);
    background: rgba(16, 185, 129, 0.15);
    border-color: rgba(16, 185, 129, 0.3);
}

/* Prism.js Override */
pre[class*="language-"] {
    margin: 0;
    padding: 0;
    background: transparent;
}

code[class*="language-"] {
    padding: var(--spacing-lg);
    background: var(--bg-code);
}

/* ===========================================
   Environment Variable Tabs
   =========================================== */

.env-tabs {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
}

.env-tab {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.env-tab:hover {
    color: var(--text-primary);
    border-color: var(--accent-primary);
    transform: translateY(-1px);
}

.env-tab.active {
    color: var(--accent-primary);
    border-color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.1);
    box-shadow: 0 0 10px rgba(99, 102, 241, 0.2);
}

.env-content {
    display: none;
}

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

/* ===========================================
   Notice Boxes
   =========================================== */

.notice {
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin: var(--spacing-lg) 0;
    font-size: 14px;
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}

.notice-info {
    background: rgba(99, 102, 241, 0.08);
    border-left: 4px solid var(--accent-primary);
    color: var(--text-secondary);
    box-shadow: 0 2px 12px rgba(99, 102, 241, 0.1);
}

.notice-warning {
    background: rgba(245, 158, 11, 0.08);
    border-left: 4px solid var(--accent-warning);
    color: var(--text-secondary);
    box-shadow: 0 2px 12px rgba(245, 158, 11, 0.1);
}

.notice-tip {
    background: rgba(16, 185, 129, 0.08);
    border-left: 4px solid #10B981;
    color: var(--text-secondary);
    box-shadow: 0 2px 12px rgba(16, 185, 129, 0.1);
}

.notice-tip .cc-switch-link {
    color: #10B981;
    font-weight: 600;
    text-decoration: none;
    border-bottom: 1px dashed #10B981;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.notice-tip .cc-switch-link:hover {
    color: #059669;
    border-bottom-style: solid;
}

.notice strong {
    color: var(--text-primary);
}

/* ===========================================
   FAQ Section
   =========================================== */

.faq-section {
    margin-top: var(--spacing-2xl);
}

.section-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
    background: linear-gradient(135deg, var(--text-primary), var(--accent-primary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.faq-item {
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-sm);
    overflow: hidden;
    background: var(--bg-card);
    transition: all var(--transition-fast);
}

.faq-item:hover {
    border-color: var(--border-glow);
    box-shadow: var(--shadow-sm);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    text-align: left;
    transition: all var(--transition-fast);
}

.faq-question:hover {
    background: var(--bg-secondary);
    padding-left: var(--spacing-xl);
}

.faq-arrow {
    color: var(--accent-primary);
    transition: transform var(--transition-base);
    flex-shrink: 0;
}

.faq-item.open .faq-arrow {
    transform: rotate(180deg);
}

.faq-item.open {
    border-color: var(--accent-primary);
    box-shadow: 0 0 15px rgba(99, 102, 241, 0.15);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    padding: 0 var(--spacing-lg);
    color: var(--text-secondary);
    font-size: 14px;
    opacity: 0;
    transition: max-height var(--transition-base), opacity var(--transition-base), padding var(--transition-base);
}

.faq-item.open .faq-answer {
    max-height: 500px;
    opacity: 1;
    padding: 0 var(--spacing-lg) var(--spacing-lg);
}

.faq-answer ol {
    margin-left: var(--spacing-xl);
}

.faq-answer li {
    margin-bottom: var(--spacing-sm);
}

/* ===========================================
   Intro Card
   =========================================== */

.intro-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    position: relative;
    overflow: hidden;
    transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.intro-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.intro-card:hover {
    transform: translate3d(0, -2px, 0);
    box-shadow: var(--shadow-card);
    border-color: var(--border-glow);
}

.intro-card:hover::before {
    opacity: 1;
}

.intro-card h2 {
    font-size: 22px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.intro-card p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

.feature-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.feature-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-secondary);
    font-size: 14px;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.feature-item:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
    transform: translateX(4px);
}

.feature-icon {
    font-size: 18px;
    transition: transform var(--transition-fast);
}

.feature-item:hover .feature-icon {
    transform: scale(1.2);
}

/* ===========================================
   Download Options
   =========================================== */

.download-options {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    text-decoration: none;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.download-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left 0.5s ease;
}

.download-btn:hover {
    border-color: var(--accent-primary);
    text-decoration: none;
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
    background: linear-gradient(135deg, var(--bg-secondary), var(--bg-card));
}

.download-btn:hover::before {
    left: 100%;
}

.download-btn.secondary {
    background: transparent;
}

.download-btn.secondary:hover {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.05), rgba(139, 92, 246, 0.05));
}

.download-icon {
    font-size: 28px;
    transition: transform var(--transition-fast);
}

.download-btn:hover .download-icon {
    transform: scale(1.15) rotate(-5deg);
}

.download-info {
    display: flex;
    flex-direction: column;
}

.download-name {
    font-weight: 600;
    color: var(--text-primary);
}

.download-desc {
    font-size: 13px;
    color: var(--text-tertiary);
}

.download-note {
    font-size: 13px;
    color: var(--text-tertiary);
}

/* ===========================================
   Numbered Steps
   =========================================== */

.numbered-steps {
    list-style: none;
    margin: 0;
    padding: 0;
    counter-reset: step-counter;
}

.numbered-steps li {
    position: relative;
    padding-left: var(--spacing-2xl);
    margin-bottom: var(--spacing-lg);
    counter-increment: step-counter;
}

.numbered-steps li::before {
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: 0;
    width: 24px;
    height: 24px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    font-size: 12px;
    font-weight: 700;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.3);
    transition: all var(--transition-fast);
}

.numbered-steps li:hover::before {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.numbered-steps strong {
    display: block;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.numbered-steps p {
    margin: 0;
    font-size: 14px;
}

/* ===========================================
   Resources Card
   =========================================== */

.resources-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-top: var(--spacing-xl);
    position: relative;
    overflow: hidden;
    transition: all var(--transition-base);
}

.resources-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-secondary), var(--accent-primary));
}

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

.resources-card h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
}

.resource-links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.resource-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    text-decoration: none;
    transition: all var(--transition-fast);
    border: 1px solid transparent;
}

.resource-link:hover {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    text-decoration: none;
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.resource-icon {
    font-size: 16px;
    transition: transform var(--transition-fast);
}

.resource-link:hover .resource-icon {
    transform: scale(1.2);
}

/* ===========================================
   Subsection (Oh-my-opencode)
   =========================================== */

.subsection {
    margin-top: var(--spacing-2xl);
    padding-top: var(--spacing-2xl);
    border-top: 1px solid var(--border-primary);
    position: relative;
}

.subsection::before {
    content: '';
    position: absolute;
    top: -1px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    border-radius: var(--radius-full);
}

.subsection-title {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 22px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xl);
}

.subsection-title::after {
    content: '';
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, var(--border-primary), transparent);
    margin-left: var(--spacing-md);
}

.subsection-icon {
    font-size: 24px;
}

.subsection .step-card h3.step-title {
    font-size: 18px;
}

/* Models List */
.models-list {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    margin-top: var(--spacing-lg);
    transition: all var(--transition-base);
}

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

.models-list h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.models-list h4::before {
    content: '🤖';
    font-size: 18px;
}

.model-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-sm);
}

.model-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    border: 1px solid transparent;
    transition: all var(--transition-fast);
}

.model-item:hover {
    border-color: var(--accent-primary);
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.05), rgba(139, 92, 246, 0.05));
    transform: translateX(4px);
}

.model-provider {
    font-size: 11px;
    font-weight: 600;
    color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.1);
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.model-item:hover .model-provider {
    background: var(--accent-primary);
    color: white;
}

.model-item code {
    font-size: 13px;
    background: transparent;
    padding: 0;
    color: var(--text-primary);
}

/* ===========================================
   Modal
   =========================================== */

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    position: relative;
    background: var(--bg-card);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    text-align: center;
    max-width: 360px;
    transform: scale(0.9) translateY(20px);
    transition: all var(--transition-base) cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.25), var(--shadow-glow);
}

.modal-overlay.active .modal-content {
    transform: scale(1) translateY(0);
}

.modal-close {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--text-tertiary);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
    cursor: pointer;
}

.modal-close:hover {
    color: white;
    background: linear-gradient(135deg, #ef4444, #f87171);
    transform: rotate(90deg);
}

.qr-large {
    max-width: 300px;
    max-height: 400px;
    width: auto;
    height: auto;
    object-fit: contain;
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
}

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

/* ===========================================
   Toast
   =========================================== */

.toast {
    position: fixed;
    bottom: var(--spacing-xl);
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-full);
    font-size: 14px;
    font-weight: 500;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base) cubic-bezier(0.34, 1.56, 0.64, 1);
    z-index: 1001;
    box-shadow: 0 10px 30px rgba(99, 102, 241, 0.4);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.toast::before {
    content: '✓';
    font-size: 16px;
    font-weight: bold;
}

.toast.active {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
    visibility: visible;
}

/* ===========================================
   Responsive
   =========================================== */

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

    .logo h1 {
        font-size: 16px;
    }

    .support-content {
        flex-direction: column;
        text-align: center;
        gap: var(--spacing-md);
    }

    .main-container {
        padding: var(--spacing-lg);
    }

    .product-tabs {
        flex-direction: column;
    }

    .product-tab {
        justify-content: center;
    }

    .product-tab.active::after {
        display: none;
    }

    .product-tab.active {
        transform: none;
        border-left: 4px solid var(--accent-primary);
    }

    .platform-tabs {
        flex-direction: column;
    }

    .step-card {
        padding: var(--spacing-lg);
    }

    .step-card:hover {
        transform: none;
    }

    .step-title {
        font-size: 18px;
    }

    .feature-list {
        grid-template-columns: 1fr;
    }

    .model-grid {
        grid-template-columns: 1fr;
    }

    .env-tabs {
        flex-direction: column;
    }

    .env-tab {
        text-align: center;
    }

    .intro-card:hover,
    .resources-card:hover,
    .download-btn:hover {
        transform: none;
    }

    .faq-item:hover {
        transform: none;
    }
}

@media (max-width: 480px) {
    .logo-icon {
        font-size: 24px;
    }

    .logo h1 {
        font-size: 14px;
    }

    .theme-btn {
        width: 32px;
        height: 32px;
    }

    .step-number {
        width: 28px;
        height: 28px;
        font-size: 12px;
    }

    .code-block code {
        font-size: 12px;
        padding: var(--spacing-md);
    }

    .modal-content {
        margin: var(--spacing-md);
        max-width: calc(100vw - 2 * var(--spacing-md));
    }

    .toast {
        left: var(--spacing-md);
        right: var(--spacing-md);
        transform: translateX(0) translateY(100px);
    }

    .toast.active {
        transform: translateX(0) translateY(0);
    }

    .resource-links {
        flex-direction: column;
    }

    .resource-link {
        justify-content: center;
    }

    .quick-guide-grid {
        grid-template-columns: 1fr;
    }
}

/* ===========================================
   Quick Guide Section
   =========================================== */

.quick-guide {
    margin-bottom: var(--spacing-xl);
}

.quick-guide-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: var(--spacing-lg);
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.quick-guide-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
}

.quick-guide-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.quick-guide-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.quick-guide-card:hover {
    border-color: var(--border-glow);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}

.quick-guide-card:hover::before {
    opacity: 1;
}

.quick-guide-card .card-icon {
    font-size: 32px;
    display: block;
    margin-bottom: var(--spacing-sm);
}

.quick-guide-card .card-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.quick-guide-card .card-recommend {
    font-size: 12px;
    color: var(--accent-primary);
    font-weight: 500;
}

/* ===========================================
   API Info Banner
   =========================================== */

.api-info-banner {
    max-width: 800px;
    margin: 1.5rem auto 2rem;
    padding: 1.2rem 1.5rem;
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.12), rgba(139, 92, 246, 0.12));
    border: 1px solid rgba(139, 92, 246, 0.3);
    border-radius: 12px;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.api-info-item {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    flex-wrap: wrap;
}

.api-info-label {
    font-weight: 600;
    color: var(--text-secondary);
    white-space: nowrap;
    min-width: 180px;
}

.api-info-value {
    background: rgba(0, 0, 0, 0.3);
    padding: 0.4rem 0.8rem;
    border-radius: 6px;
    font-size: 0.95rem;
    color: #a78bfa;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
}

.api-info-value:hover {
    background: rgba(0, 0, 0, 0.5);
}

.api-info-value.copied::after {
    content: '✓ 已复制';
    position: absolute;
    right: -60px;
    color: #34d399;
    font-size: 0.8rem;
    white-space: nowrap;
}

.api-info-desc {
    color: var(--text-tertiary);
    font-size: 0.9rem;
}

@media (max-width: 600px) {
    .api-info-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.3rem;
    }
    .api-info-label {
        min-width: auto;
    }
    .api-info-value.copied::after {
        right: auto;
        left: 0;
        top: -1.2rem;
    }
}

/* ===========================================
   Placeholder Box (Screenshot Placeholders)
   =========================================== */

.step-image.placeholder {
    border: 2px dashed var(--border-primary);
    background: var(--bg-secondary);
    box-shadow: none;
}

.placeholder-box {
    padding: var(--spacing-xl) var(--spacing-lg);
    text-align: center;
    color: var(--text-tertiary);
    font-size: 14px;
}

/* ===========================================
   Notice Success (Green)
   =========================================== */

.notice-success {
    background: rgba(16, 185, 129, 0.1);
    border-left: 4px solid var(--accent-success);
    color: var(--text-secondary);
    box-shadow: 0 2px 12px rgba(16, 185, 129, 0.1);
}

.notice-success strong {
    color: var(--accent-success);
}

/* ===========================================
   Notice Danger (Red)
   =========================================== */

.notice-danger {
    background: rgba(239, 68, 68, 0.08);
    border-left: 4px solid var(--accent-error);
    color: var(--text-secondary);
    box-shadow: 0 2px 12px rgba(239, 68, 68, 0.1);
}

.notice-danger strong {
    color: var(--accent-error);
}

/* ===========================================
   Manual Setup Collapsible
   =========================================== */

.manual-setup details {
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    margin-top: var(--spacing-md);
    overflow: hidden;
    transition: all var(--transition-fast);
}

.manual-setup details[open] {
    border-color: var(--border-glow);
}

.manual-setup details summary {
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 15px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    background: var(--bg-secondary);
    transition: all var(--transition-fast);
    list-style: none;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.manual-setup details summary::-webkit-details-marker {
    display: none;
}

.manual-setup details summary::before {
    content: '▶';
    font-size: 10px;
    transition: transform var(--transition-fast);
}

.manual-setup details[open] summary::before {
    transform: rotate(90deg);
}

.manual-setup details summary:hover {
    color: var(--text-primary);
    background: var(--bg-card);
}

.manual-setup details .details-content {
    padding: var(--spacing-lg);
}

/* ===========================================
   Recommended Badge
   =========================================== */

.recommended-badge {
    display: inline-block;
    font-size: 11px;
    font-weight: 700;
    color: white;
    background: linear-gradient(135deg, var(--accent-success), #059669);
    padding: 2px 8px;
    border-radius: var(--radius-full);
    margin-left: var(--spacing-sm);
    vertical-align: middle;
    animation: pulse 2s ease-in-out infinite;
}

.one-click-setup {
    border: 2px solid var(--accent-success);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin: var(--spacing-md) 0;
    background: rgba(16, 185, 129, 0.05);
    position: relative;
}

/* ===========================================
   Print Styles
   =========================================== */

@media print {
    .header,
    .support-bar,
    .theme-switcher,
    .platform-tabs,
    .product-tabs,
    .modal-overlay,
    .toast {
        display: none !important;
    }

    body {
        background: white;
        color: black;
    }

    .product-content,
    .platform-content {
        display: block !important;
    }

    .step-card {
        break-inside: avoid;
        border: 1px solid #ccc;
    }
}