:root {
    --primary: #E85A4F;
    --primary-dark: #D1483E;
    --primary-light: #FF7A70;
    --bg: #0A0A0F;
    --bg-secondary: #111118;
    --bg-tertiary: #1A1A23;
    --text: #FFFFFF;
    --text-secondary: #A0A0A8;
    --text-muted: #6B7280;
    --border: rgba(255, 255, 255, 0.1);
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-glow: 0 0 40px -10px rgba(232, 90, 79, 0.3);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Particle Canvas Background */
#particle-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: linear-gradient(135deg, #0a0a0f 0%, #111118 50%, #0d0d12 100%);
}

/* Navigation */
nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 1rem 2rem;
    background: rgba(10, 10, 15, 0.9);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary);
}

.logo-icon {
    width: 44px;
    height: 44px;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.logo-icon svg {
    width: 38px;
    height: 38px;
    transform: translate(2px, 2px);
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    font-size: 0.95rem;
}

.nav-links a:hover {
    color: var(--primary-light);
}

.nav-cta {
    background: var(--primary);
    color: white !important;
    padding: 0.5rem 1.25rem;
    border-radius: 6px;
    font-weight: 600 !important;
    transition: all 0.2s ease;
}

.nav-cta:hover {
    background: var(--primary-light);
}

.nav-cta:active {
    transform: translateY(1px);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 8rem 2rem 4rem;
    position: relative;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-content {
    animation: fadeInUp 1s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(232, 90, 79, 0.1);
    border: 1px solid rgba(232, 90, 79, 0.2);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: 1.5rem;
}

.badge::before {
    content: '';
    width: 8px;
    height: 8px;
    background: var(--primary);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    letter-spacing: -0.02em;
}

h1 .red-text {
    color: var(--primary);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 2rem;
}

.hero-download-btn {
    padding: 1rem 2.5rem !important;
    font-size: 1.2rem !important;
    font-weight: 600;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    transition: all 0.2s ease;
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    background: var(--primary-light);
    box-shadow: 0 4px 12px rgba(232, 90, 79, 0.3);
}

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

.btn-secondary {
    background: transparent;
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.25);
    transition: all 0.2s ease;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.4);
}

.hero-stats {
    display: flex;
    gap: 2rem;
}

.stat {
    text-align: center;
}

.stat-value {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--primary);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* Hero Visual */
.hero-visual {
    position: relative;
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

.hero-card {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 2rem;
    box-shadow: var(--shadow-lg);
    display: flex;
    flex-direction: column;
}

.hero-card .chat-bubble {
    align-self: flex-start;
    max-width: 90%;
}

.hero-card-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.hero-card-avatar {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-card-avatar svg {
    width: 40px;
    height: 40px;
    transform: translate(2px, 2px);
}

.hero-card-info h3 {
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.hero-card-info p {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.chat-bubble {
    background: rgba(232, 90, 79, 0.15);
    border: 1px solid rgba(232, 90, 79, 0.2);
    border-radius: 16px;
    padding: 1rem 1.25rem;
    margin-bottom: 0.75rem;
    font-size: 0.95rem;
    color: white;
    opacity: 0;
    transform: translateY(10px);
    animation: fadeInUp 0.5s ease forwards;
}

.chat-bubble.msg-1 {
    animation-delay: 0.5s;
    align-self: flex-start;
}

.chat-bubble.msg-2 {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    align-self: flex-end;
    max-width: 85%;
    animation-delay: 1.2s;
}

.chat-bubble.msg-3 {
    animation-delay: 1.9s;
    align-self: flex-start;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Features Section */
.features {
    padding: 6rem 2rem;
    background: var(--bg);
}

.section-container {
    max-width: 1200px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-tag {
    display: inline-block;
    background: rgba(232, 90, 79, 0.1);
    color: var(--primary);
    padding: 0.5rem 1rem;
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

h2 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}

.feature-card {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 2rem;
    transition: all 0.3s;
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--primary);
    transform: scaleX(0);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: rgba(232, 90, 79, 0.3);
    box-shadow: 0 0 40px -10px rgba(232, 90, 79, 0.2);
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    width: 56px;
    height: 56px;
    background: rgba(232, 90, 79, 0.15);
    border: 1px solid rgba(232, 90, 79, 0.2);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    margin-bottom: 1.25rem;
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Use Cases Section */
.use-cases {
    padding: 6rem 2rem;
    background: var(--bg-secondary);
}

.demo-showcase {
    max-width: 1000px;
    margin: 0 auto 3rem;
}

.demo-screen {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 25px 80px -20px rgba(0, 0, 0, 0.6);
}

.demo-header {
    background: rgba(255, 255, 255, 0.03);
    padding: 1rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border);
}

.demo-header > span {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.6);
}

.demo-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(232, 90, 79, 0.1);
    border: 1px dashed rgba(232, 90, 79, 0.3);
    border-radius: 8px;
}

.demo-actions span {
    font-size: 0.8rem;
    color: var(--primary-light);
}

.demo-content {
    padding: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.demo-content .demo-preview-img {
    width: 100%;
    max-width: 900px;
    height: auto;
    border-radius: 12px;
    display: block;
}

.demo-placeholder {
    text-align: center;
    max-width: 400px;
}

.placeholder-icon {
    font-size: 5rem;
    margin-bottom: 1.5rem;
    opacity: 0.5;
}

.demo-placeholder h4 {
    font-size: 1.25rem;
    color: white;
    margin-bottom: 0.75rem;
}

.demo-placeholder p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.placeholder-hints {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.placeholder-hints span {
    font-size: 0.8rem;
    color: var(--text-muted);
    background: rgba(255, 255, 255, 0.05);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    display: inline-block;
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    max-width: 1000px;
    margin: 0 auto;
}

.use-case-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1rem 1.25rem;
    transition: all 0.3s;
}

.use-case-item:hover {
    border-color: rgba(232, 90, 79, 0.3);
    transform: translateY(-2px);
}

.use-case-icon {
    font-size: 1.25rem;
}

.use-case-text {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.9);
}

/* Install Section */
.install {
    padding: 6rem 2rem;
}

.install-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: start;
}

/* Install Showcase */
.install-showcase {
    max-width: 900px;
    margin: 0 auto 4rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    align-items: stretch;
}

.showcase-main {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.showcase-img-wrap {
    border-radius: 12px;
    overflow: hidden;
    aspect-ratio: 16/10;
    background: var(--bg-tertiary);
}

.showcase-img-wrap .showcase-main-img {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
}

.setup-wizard {
    text-align: center;
    max-width: 300px;
}

.wizard-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.setup-wizard h4 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: white;
}

.setup-wizard p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.wizard-progress {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.progress-step {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.875rem;
    font-weight: 600;
    color: rgba(255, 255, 255, 0.5);
    border: 2px solid rgba(255, 255, 255, 0.1);
}

.progress-step.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.progress-line {
    width: 40px;
    height: 2px;
    background: rgba(255, 255, 255, 0.1);
}

.wizard-btn {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 2rem;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

.wizard-btn:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
}

.showcase-gallery {
    display: flex;
    flex-direction: row;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.gallery-item {
    cursor: pointer;
    transition: all 0.3s;
    flex: 1 1 160px;
    max-width: 220px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.gallery-item:hover {
    transform: translateY(-4px);
}

.gallery-item.active .gallery-thumb {
    border-color: var(--primary);
    background: rgba(232, 90, 79, 0.1);
}

.gallery-item.active .gallery-step-label {
    color: var(--primary);
}

.gallery-thumb {
    background: var(--bg-tertiary);
    border: 2px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    aspect-ratio: 16/10;
    width: 100%;
}

.gallery-thumb img {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
}

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


@media (max-width: 768px) {
    .gallery-item {
        flex: 1 1 calc(50% - 0.5rem);
        max-width: none;
    }
}

.install-content h3 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--text);
}

.sys-requirements {
    margin-top: 2rem;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.requirement-item span:first-child {
    font-size: 1.5rem;
}

.requirement-item span:last-child {
    font-size: 0.9rem;
    font-weight: 500;
}

.install-steps {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.step {
    display: flex;
    gap: 1rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.5rem;
    transition: all 0.3s;
}

.step:hover {
    border-color: rgba(232, 90, 79, 0.3);
    transform: translateX(5px);
}

.step-number {
    width: 40px;
    height: 40px;
    background: var(--primary);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.125rem;
    flex-shrink: 0;
}

.step-content h4 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.step-content p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Download Card */
.download-card {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 2.5rem;
    position: sticky;
    top: 100px;
    box-shadow: var(--shadow-lg);
}

.download-btn-wrapper {
    position: relative;
    margin-top: 1.5rem;
    margin-bottom: 1rem;
}

.download-badge {
    position: absolute;
    top: -10px;
    right: 10px;
    background: #F59E0B;
    color: #1a1a1a;
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 700;
    z-index: 10;
}

.download-btn {
    width: 100%;
    padding: 1.25rem 2rem !important;
    font-size: 1.1rem !important;
    font-weight: 600;
    display: flex !important;
    flex-direction: column;
    align-items: center;
    gap: 0.4rem;
}

.download-btn .btn-text {
    font-weight: 600;
}

.download-btn .btn-version {
    font-size: 0.75rem;
    opacity: 0.7;
    font-weight: 500;
}

.download-hint {
    text-align: center;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin: 0.5rem 0 0;
}

.download-meta {
    display: flex;
    justify-content: space-between;
    padding: 1rem 0;
    border-top: 1px solid var(--border);
    font-size: 0.875rem;
    color: var(--text-muted);
}

.cn-optimize {
    background: rgba(232, 90, 79, 0.1);
    border: 1px solid rgba(232, 90, 79, 0.2);
    border-radius: 12px;
    padding: 1rem;
    margin-top: 1.5rem;
}

.cn-optimize h4 {
    color: var(--primary-light);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.cn-optimize ul {
    list-style: none;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.7);
}

.cn-optimize li {
    padding: 0.25rem 0;
    padding-left: 1rem;
    position: relative;
}

.cn-optimize li::before {
    content: '•';
    color: var(--primary);
    position: absolute;
    left: 0;
}

/* FAQ Section */
.faq {
    padding: 6rem 2rem;
    background: var(--bg);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.faq-item {
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
    transition: all 0.3s;
}

.faq-item:hover {
    border-color: rgba(232, 90, 79, 0.3);
}

.faq-question {
    width: 100%;
    padding: 1.5rem;
    background: none;
    border: none;
    color: white;
    font-size: 1.1rem;
    font-weight: 600;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: inherit;
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    color: var(--primary);
    transition: transform 0.3s;
}

.faq-item.active .faq-question::after {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer p {
    padding: 0 1.5rem 1.5rem;
    color: var(--text-muted);
    line-height: 1.7;
}

/* Footer */
footer {
    padding: 4rem 2rem 2rem;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
}

.footer-brand {
    max-width: 300px;
}

.footer-brand .logo {
    margin-bottom: 1rem;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.9rem;
    line-height: 1.6;
}

.footer-links h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: white;
}

.footer-links ul {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--primary-light);
}

.footer-bottom {
    max-width: 1200px;
    margin: 3rem auto 0;
    padding-top: 2rem;
    border-top: 1px solid var(--border);
    text-align: center;
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 1024px) {
    .hero-container,
    .install-grid {
        grid-template-columns: 1fr;
    }

    .hero-visual {
        order: -1;
    }

    .download-card {
        position: static;
    }

    .footer-container {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    h1 {
        font-size: 2.5rem;
    }

    h2 {
        font-size: 2rem;
    }

    .nav-links {
        display: none;
    }

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

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }

    .footer-container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-brand {
        max-width: 100%;
    }
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--primary);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    transform: translateY(100px);
    opacity: 0;
    transition: all 0.3s;
    z-index: 9999;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

/* ========== 使用手册页面 ========== */
.help-page .help-main {
    padding: 6rem 2rem 4rem;
    min-height: 100vh;
}

.help-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 3rem;
    align-items: start;
}

.help-sidebar {
    position: sticky;
    top: 6rem;
}

.help-sidebar-inner {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem 1rem;
}

/* 重置侧边栏内 nav，避免继承顶部导航的 fixed 等样式 */
.help-sidebar nav,
.help-toc {
    position: static;
    top: auto;
    left: auto;
    right: auto;
    z-index: auto;
    padding: 0;
    background: transparent;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    border-bottom: none;
}

.help-toc-title {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 1rem;
    padding: 0 0.25rem;
}

.help-toc ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.help-toc > ul > li {
    margin-bottom: 0.75rem;
}

.help-toc > ul > li:last-child {
    margin-bottom: 0;
}

.help-toc > ul > li > ul {
    margin: 0.35rem 0 0 0.75rem;
    padding: 0 0 0 0.75rem;
    border-left: 1px solid var(--border);
}

.help-toc > ul > li > ul > li {
    margin-bottom: 0.25rem;
}

.help-toc > ul > li > ul > li:last-child {
    margin-bottom: 0;
}

.help-toc a {
    display: block;
    padding: 0.35rem 0.5rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 6px;
    transition: color 0.2s, background 0.2s;
}

.help-toc a:hover {
    color: var(--primary-light);
    background: rgba(232, 90, 79, 0.08);
}

.help-toc > ul > li > a {
    font-weight: 600;
    color: var(--text);
}

.help-content {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2.5rem 3rem;
}

.help-header {
    margin-bottom: 2.5rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border);
}

.help-header h1 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
}

.help-desc {
    color: var(--text-muted);
    font-size: 1.05rem;
}

.help-section {
    margin-bottom: 2.5rem;
}

.help-section h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 1.25rem;
    padding-top: 0.5rem;
}

.help-section h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin: 1.5rem 0 0.75rem;
    color: var(--text);
}

.help-section p,
.help-section ul {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.7;
}

.help-section ul {
    padding-left: 1.5rem;
}

.help-section li {
    margin-bottom: 0.5rem;
}

.help-section a {
    color: var(--primary-light);
    text-decoration: none;
}

.help-section a:hover {
    text-decoration: underline;
}

/* 使用手册配图占位 */
.help-fig {
    margin: 1.25rem 0;
}

.help-fig-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    min-height: 180px;
    padding: 1rem 1.5rem;
    background: var(--bg-tertiary);
    border: 1px dashed var(--border);
    border-radius: 12px;
    color: var(--text-muted);
    text-align: center;
}

.help-fig-icon {
    font-size: 2rem;
    opacity: 0.7;
}

.help-fig-text {
    font-size: 0.875rem;
}

.help-fig-hint {
    font-size: 0.8125rem;
    color: var(--text-muted);
    line-height: 1.5;
    max-width: 420px;
}

.help-fig-caption {
    margin-top: 0.5rem;
    font-size: 0.8125rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* 替换为真实图片时使用：.help-fig img { width: 100%; max-width: 720px; height: auto; border-radius: 8px; } */
.help-fig img {
    width: 100%;
    max-width: 720px;
    height: auto;
    border-radius: 8px;
    display: block;
}

.logo-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: inherit;
    text-decoration: none;
}

.nav-active {
    color: var(--primary-light) !important;
}

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

    .help-sidebar {
        position: static;
    }

    .help-sidebar-inner {
        max-height: 280px;
        overflow-y: auto;
    }
}

@media (max-width: 768px) {
    .help-page .help-main {
        padding: 5rem 1rem 3rem;
    }

    .help-content {
        padding: 1.5rem 1.25rem;
    }

    .help-header h1 {
        font-size: 1.5rem;
    }
}