/* ===== RESET & BASE ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #3B82F6;
    --primary-dark: #1542c2;
    --primary-light: #5b91ff;
    --primary-50: #eef5ff;
    --primary-100: #d9e8ff;
    --secondary: #14b8a6;
    --secondary-light: #2dd4bf;
    --accent: #FF5630;
    --warning: #FFAB00;
    --warning-bg: #FFF8E1;
    --info: #3B82F6;
    --info-bg: #eef5ff;
    --success: #14b8a6;
    --success-bg: #f0fdfa;
    --highlight-bg: #eef5ff;
    --text-primary: #1e3a5f;
    --text-secondary: #4b5563;
    --text-light: #9ca3af;
    --border: #dbeafe;
    --border-light: #eff6ff;
    --bg-white: #FFFFFF;
    --bg-light: #f8fafc;
    --bg-page: #e5e7eb;
    --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 8px 30px rgba(0,0,0,0.12);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--text-primary);
    background: var(--bg-page);
    margin: 0 5px;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

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

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

/* ===== HEADER ===== */
.header {
    background: #ffffff;
    color: var(--text-primary);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-md);
    border-bottom: 2px solid var(--border);
}

.header-container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.header-left .logo-link {
    color: var(--primary-dark);
    font-size: 1.2rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
}

.header-left .logo-link i {
    font-size: 1.4rem;
}

.header-center h1 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.header-right .btn-kb {
    background: var(--primary);
    color: #fff;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.85rem;
    font-weight: 500;
    text-decoration: none;
    transition: var(--transition);
}

.header-right .btn-kb:hover {
    background: var(--primary-dark);
    text-decoration: none;
}

/* ===== HERO ===== */
.hero {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary), var(--primary-light));
    color: #fff;
    padding: 60px 24px 50px;
    text-align: center;
}

.hero-container {
    max-width: 700px;
    margin: 0 auto;
}

.hero h2 {
    font-size: 2.2rem;
    font-weight: 800;
    margin-bottom: 12px;
}

.hero p {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 30px;
}

.search-box {
    position: relative;
    max-width: 550px;
    margin: 0 auto;
}

.search-box i {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-light);
    font-size: 1rem;
}

.search-box input {
    width: 100%;
    padding: 14px 18px 14px 48px;
    border: none;
    border-radius: 50px;
    font-size: 1rem;
    font-family: inherit;
    box-shadow: var(--shadow-lg);
    outline: none;
    transition: var(--transition);
}

.search-box input:focus {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.4), var(--shadow-lg);
}

/* ===== QUICK NAV ===== */
/* ===== TOPIC CARDS NAVIGATION ===== */
.topics-nav {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    padding: 32px 24px;
}

.topics-nav-container {
    max-width: 1100px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.topic-nav-card {
    position: relative;
    background: var(--bg-white);
    border: 2px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    cursor: pointer;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: center;
    overflow: hidden;
}

.topic-nav-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.topic-nav-card:nth-child(2)::before {
    background: linear-gradient(135deg, #6366f1, #818cf8);
}

.topic-nav-card:nth-child(3)::before {
    background: linear-gradient(135deg, #25D366, #128C7E);
}

.topic-nav-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 32px rgba(59, 130, 246, 0.15);
    border-color: var(--primary-light);
}

.topic-nav-card:hover::before {
    opacity: 1;
}

.topic-nav-card:nth-child(2):hover {
    box-shadow: 0 12px 32px rgba(99, 102, 241, 0.15);
    border-color: #818cf8;
}

.topic-nav-card:nth-child(3):hover {
    box-shadow: 0 12px 32px rgba(37, 211, 102, 0.15);
    border-color: #25D366;
}

.topic-nav-card:active {
    transform: translateY(-2px) scale(0.98);
}

.topic-nav-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 1.4rem;
    margin: 0 auto 16px;
    transition: transform 0.3s ease;
}

.topic-nav-card:hover .topic-nav-icon {
    transform: scale(1.1) rotate(-3deg);
}

.topic-nav-card h3 {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0 0 8px;
}

.topic-nav-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin: 0 0 14px;
    line-height: 1.5;
}

.topic-nav-count {
    display: inline-block;
    background: var(--primary-50);
    color: var(--primary);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 4px 14px;
    border-radius: 50px;
    border: 1px solid var(--border);
}

/* ===== CATEGORY HIGHLIGHT ANIMATION ===== */
@keyframes categoryGlow {
    0% {
        box-shadow: 0 0 0 0 rgba(59, 130, 246, 0.4);
    }
    40% {
        box-shadow: 0 0 20px 8px rgba(59, 130, 246, 0.25);
    }
    100% {
        box-shadow: 0 0 0 0 rgba(59, 130, 246, 0);
    }
}

@keyframes categorySlideIn {
    from {
        opacity: 0.7;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.category-group.category-highlight .category-header {
    animation: categoryGlow 1.5s ease-out, categorySlideIn 0.4s ease-out;
    border-color: var(--primary);
    background: linear-gradient(135deg, var(--primary-50), rgba(59, 130, 246, 0.08));
}

.category-group.category-highlight .help-section {
    animation: categorySlideIn 0.5s ease-out backwards;
}

.category-group.category-highlight .help-section:nth-child(2) { animation-delay: 0.05s; }
.category-group.category-highlight .help-section:nth-child(3) { animation-delay: 0.1s; }
.category-group.category-highlight .help-section:nth-child(4) { animation-delay: 0.15s; }
.category-group.category-highlight .help-section:nth-child(5) { animation-delay: 0.2s; }
.category-group.category-highlight .help-section:nth-child(6) { animation-delay: 0.25s; }
.category-group.category-highlight .help-section:nth-child(7) { animation-delay: 0.3s; }
.category-group.category-highlight .help-section:nth-child(8) { animation-delay: 0.35s; }

/* ===== MAIN CONTENT ===== */
.main-content {
    max-width: 960px;
    margin: 0 auto;
    padding: 32px 24px 60px;
}

/* ===== CATEGORY GROUPS ===== */
.category-group {
    margin-bottom: 56px;
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-left: 5px solid var(--primary);
    border-radius: var(--radius-lg);
    padding: 28px 24px 24px;
    box-shadow: var(--shadow-sm);
    position: relative;
}

.category-group#cat-infraestrutura {
    border-left-color: #6366f1;
}

.category-group#cat-ferramentas {
    border-left-color: #25D366;
}

.category-header {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px 24px;
    margin-bottom: 24px;
    background: linear-gradient(135deg, var(--primary-50), var(--bg-white));
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    position: relative;
}

#cat-infraestrutura .category-header {
    background: linear-gradient(135deg, #eef2ff, var(--bg-white));
}

#cat-infraestrutura .category-icon {
    background: linear-gradient(135deg, #6366f1, #818cf8);
}

#cat-ferramentas .category-header {
    background: linear-gradient(135deg, #f0fdf4, var(--bg-white));
}

#cat-ferramentas .category-icon {
    background: linear-gradient(135deg, #25D366, #128C7E);
}

.category-header::after {
    content: '';
    position: absolute;
    bottom: -13px;
    left: 40px;
    width: 2px;
    height: 12px;
    background: var(--border);
}

.category-icon {
    width: 48px;
    height: 48px;
    border-radius: 14px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.category-title {
    font-size: 1.3rem;
    font-weight: 800;
    color: var(--text-primary);
    margin: 0;
}

.category-desc {
    font-size: 0.88rem;
    color: var(--text-secondary);
    margin: 2px 0 0;
}

.category-badge {
    margin-left: auto;
    background: var(--primary-50);
    color: var(--primary);
    font-size: 0.78rem;
    font-weight: 600;
    padding: 4px 12px;
    border-radius: 50px;
    white-space: nowrap;
    border: 1px solid var(--border);
}

/* ===== SECTION ===== */
.help-section {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    margin-bottom: 20px;
    overflow: hidden;
    border: 1px solid var(--border-light);
    transition: var(--transition);
}

.category-group .help-section:last-of-type {
    margin-bottom: 0;
}

.help-section:hover {
    box-shadow: var(--shadow-md);
}

.section-header {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 24px 28px;
    background: linear-gradient(135deg, var(--primary-50), var(--primary-100));
    border-bottom: 1px solid var(--border-light);
}

.section-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.section-header h2 {
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
}

.section-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-top: 2px;
}

.section-body {
    padding: 28px;
}

.section-body p {
    margin-bottom: 14px;
    font-size: 0.95rem;
    line-height: 1.8;
}

.section-body h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin: 28px 0 14px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.section-body h3 i {
    color: var(--primary);
    font-size: 1rem;
}

.section-body h4 {
    font-size: 1rem;
    font-weight: 600;
    margin: 16px 0 10px;
    color: var(--text-primary);
}

/* ===== INFO CARDS ===== */
.info-card {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    padding: 16px 20px;
    border-radius: var(--radius-md);
    margin-bottom: 16px;
    border-left: 4px solid;
}

.info-card.highlight {
    background: linear-gradient(135deg, var(--primary-50), var(--primary-100));
    border-color: var(--primary);
}

.info-card.info {
    background: var(--info-bg);
    border-color: var(--info);
}

.info-card.warning {
    background: var(--warning-bg);
    border-color: var(--warning);
}

.info-card.success {
    background: var(--success-bg);
    border-color: var(--success);
}

.info-card-icon {
    font-size: 1.2rem;
    flex-shrink: 0;
    margin-top: 2px;
}

.info-card.highlight .info-card-icon { color: var(--primary); }
.info-card.info .info-card-icon { color: var(--info); }
.info-card.warning .info-card-icon { color: #F29D12; }
.info-card.success .info-card-icon { color: var(--success); }

.info-card-content p {
    margin-bottom: 6px;
    font-size: 0.93rem;
}

.info-card-content p:last-child {
    margin-bottom: 0;
}

.info-card.small {
    padding: 12px 16px;
    margin-bottom: 12px;
}

.info-card.small .info-card-icon {
    font-size: 1rem;
}

.info-card.small .info-card-content p {
    font-size: 0.88rem;
}

/* ===== CHECK LIST ===== */
.check-list {
    list-style: none;
    padding: 0;
    margin-bottom: 16px;
}

.check-list li {
    padding: 8px 0;
    font-size: 0.93rem;
    display: flex;
    align-items: center;
    gap: 10px;
    border-bottom: 1px solid var(--border-light);
}

.check-list li:last-child {
    border-bottom: none;
}

.check-list li i {
    color: var(--secondary);
    font-size: 0.85rem;
    flex-shrink: 0;
}

/* ===== STEPS TIMELINE ===== */
.steps-timeline {
    position: relative;
    padding-left: 40px;
    margin: 20px 0;
}

.steps-timeline::before {
    content: '';
    position: absolute;
    left: 16px;
    top: 0;
    bottom: 0;
    width: 2px;
    background: linear-gradient(to bottom, var(--primary), var(--secondary));
    border-radius: 1px;
}

.step {
    position: relative;
    margin-bottom: 24px;
    display: flex;
    align-items: flex-start;
    gap: 16px;
}

.step:last-child {
    margin-bottom: 0;
}

.step-number {
    position: absolute;
    left: -40px;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.85rem;
    z-index: 1;
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.step-content {
    background: var(--bg-light);
    padding: 14px 18px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-light);
    flex: 1;
}

.step-content h4 {
    font-size: 0.95rem;
    font-weight: 600;
    margin: 0 0 4px;
    color: var(--primary-dark);
}

.step-content p {
    margin: 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ===== STEPS LIST ===== */
.steps-list {
    margin: 16px 0;
}

.step-item {
    display: flex;
    gap: 16px;
    padding: 16px 0;
    border-bottom: 1px solid var(--border-light);
}

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

.step-badge {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.9rem;
    flex-shrink: 0;
    box-shadow: 0 2px 6px rgba(59, 130, 246, 0.2);
}

.step-detail {
    flex: 1;
}

.step-detail h4 {
    font-size: 1rem;
    font-weight: 600;
    margin: 0 0 6px;
    color: var(--text-primary);
}

.step-detail p {
    margin: 0 0 8px;
    font-size: 0.93rem;
}

.steps-list.compact .step-item {
    padding: 10px 0;
}

.steps-list.compact .step-badge {
    width: 28px;
    height: 28px;
    font-size: 0.8rem;
}

/* ===== CONFIG LIST ===== */
.config-list {
    list-style: none;
    padding: 0;
    margin: 8px 0;
}

.config-list li {
    padding: 6px 0;
    font-size: 0.9rem;
    display: flex;
    align-items: flex-start;
    gap: 8px;
}

.config-list li::before {
    content: '•';
    color: var(--primary);
    font-weight: 700;
    font-size: 1.2rem;
    line-height: 1.2;
}

/* ===== TIP BOX ===== */
.tip-box {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 12px 16px;
    background: #FFF9E6;
    border-radius: var(--radius-sm);
    border: 1px solid #FFE49A;
    margin: 12px 0;
    font-size: 0.88rem;
    color: #5B4A00;
}

.tip-box i {
    color: #D4A017;
    font-size: 1rem;
    flex-shrink: 0;
    margin-top: 2px;
}

/* ===== REQUIREMENTS BOX ===== */
.requirements-box {
    background: linear-gradient(135deg, #FFF5F5, #FFF0F0);
    border: 1px solid #FECACA;
    border-radius: var(--radius-md);
    padding: 20px 24px;
    margin-bottom: 20px;
}

.requirements-box h4 {
    font-size: 1rem;
    font-weight: 700;
    color: var(--accent);
    margin: 0 0 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.requirements-box ul {
    list-style: none;
    padding: 0;
}

.requirements-box li {
    padding: 6px 0;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.requirements-box li i {
    color: var(--accent);
    font-size: 0.85rem;
}

/* ===== EXAMPLE BOX ===== */
.example-box {
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    margin: 20px 0;
}

.example-box h4 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--primary-dark);
    margin: 0 0 20px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.example-flow {
    display: flex;
    align-items: stretch;
    gap: 12px;
    margin-bottom: 20px;
    flex-wrap: wrap;
    justify-content: center;
}

.flow-item {
    flex: 1;
    min-width: 180px;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 16px;
    border: 1px solid var(--border-light);
    text-align: center;
}

.flow-number {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.85rem;
    margin-bottom: 10px;
}

.flow-item p {
    font-size: 0.88rem;
    margin: 0;
}

.flow-arrow {
    display: flex;
    align-items: center;
    color: var(--primary-light);
    font-size: 1.2rem;
}

.result-box {
    background: var(--success-bg);
    padding: 14px 18px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.93rem;
}

.result-box i {
    color: var(--success);
    font-size: 1.2rem;
}

/* ===== TOPICS GRID ===== */
.topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 14px;
    margin: 20px 0;
}

.topic-card {
    background: var(--bg-light);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 18px;
    text-align: center;
    transition: var(--transition);
}

.topic-card:hover {
    border-color: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.topic-card i {
    font-size: 1.6rem;
    color: var(--primary);
    margin-bottom: 10px;
    display: block;
}

.topic-card h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin: 0 0 4px;
}

.topic-card p {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin: 0;
}

/* ===== FEATURES GRID ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 14px;
    margin: 16px 0;
}

.feature-item {
    background: var(--bg-light);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 16px;
    text-align: center;
    transition: var(--transition);
}

.feature-item:hover {
    border-color: var(--primary-light);
    box-shadow: var(--shadow-sm);
}

.feature-item i {
    color: var(--primary);
    font-size: 1.4rem;
    margin-bottom: 8px;
    display: block;
}

.feature-item h4 {
    font-size: 0.88rem;
    font-weight: 600;
    margin: 0 0 4px;
}

.feature-item p {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin: 0;
}

/* ===== SUBSECTION ===== */
.subsection {
    margin: 28px 0;
    padding-top: 20px;
    border-top: 1px solid var(--border-light);
}

.subsection:first-child {
    border-top: none;
    padding-top: 0;
}

/* ===== COLLAPSIBLE ===== */
.collapsible-section {
    margin: 14px 0;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.collapsible-btn {
    width: 100%;
    background: var(--bg-light);
    border: none;
    padding: 14px 18px;
    font-size: 0.95rem;
    font-weight: 600;
    font-family: inherit;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    transition: var(--transition);
}

.collapsible-btn:hover {
    background: var(--info-bg);
}

.collapsible-btn i:first-child {
    color: var(--primary);
}

.toggle-icon {
    margin-left: auto;
    transition: transform 0.3s ease;
    color: var(--text-light);
}

.toggle-icon.rotated {
    transform: rotate(180deg);
}

.collapsible-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.3s ease;
    padding: 0 18px;
}

.collapsible-content.open {
    max-height: 800px;
    padding: 16px 18px;
    border-top: 1px solid var(--border-light);
}

/* ===== CONTACT CARDS ===== */
.contact-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
}

.contact-card {
    background: var(--bg-light);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 24px;
    text-align: center;
    transition: var(--transition);
}

.contact-card:hover {
    border-color: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.contact-card i {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 12px;
    display: block;
}

.contact-card h4 {
    font-size: 0.95rem;
    font-weight: 600;
    margin: 0 0 8px;
}

.contact-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 4px 0;
}

.contact-card a {
    font-size: 0.88rem;
    font-weight: 500;
}

/* ===== BACK TO TOP ===== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff;
    border: none;
    cursor: pointer;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: var(--transition);
    z-index: 50;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

/* ===== FOOTER ===== */
.footer {
    background: var(--text-primary);
    color: rgba(255,255,255,0.7);
    text-align: center;
    padding: 24px;
    font-size: 0.85rem;
}

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

.footer p {
    margin: 4px 0;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .category-header {
        padding: 16px;
        gap: 12px;
    }

    .category-icon {
        width: 40px;
        height: 40px;
        font-size: 1rem;
        border-radius: 10px;
    }

    .category-title {
        font-size: 1.1rem;
    }

    .category-badge {
        display: none;
    }

    .category-group {
        margin-bottom: 36px;
        padding: 18px 12px 16px;
    }

    .header-container {
        flex-wrap: wrap;
        height: auto;
        padding: 12px 16px;
        gap: 8px;
    }

    .header-center h1 {
        font-size: 0.95rem;
    }

    .header-right .btn-kb {
        display: none;
    }

    .hero {
        padding: 40px 16px 36px;
    }

    .hero h2 {
        font-size: 1.6rem;
    }

    .hero p {
        font-size: 0.95rem;
    }

    .topics-nav {
        padding: 20px 16px;
    }

    .topics-nav-container {
        grid-template-columns: 1fr;
        gap: 14px;
    }

    .topic-nav-card {
        padding: 20px 18px;
        display: flex;
        align-items: center;
        text-align: left;
        gap: 16px;
    }

    .topic-nav-icon {
        margin: 0;
        width: 44px;
        height: 44px;
        min-width: 44px;
        font-size: 1.1rem;
        border-radius: 12px;
    }

    .topic-nav-card h3 {
        font-size: 1rem;
        margin-bottom: 2px;
    }

    .topic-nav-card p {
        font-size: 0.8rem;
        margin-bottom: 6px;
    }

    .main-content {
        padding: 20px 12px 40px;
    }

    .section-header {
        padding: 18px 20px;
    }

    .section-header h2 {
        font-size: 1.15rem;
    }

    .section-body {
        padding: 20px;
    }

    .example-flow {
        flex-direction: column;
    }

    .flow-arrow {
        justify-content: center;
        transform: rotate(90deg);
    }

    .steps-timeline {
        padding-left: 36px;
    }

    .step-number {
        left: -36px;
        width: 28px;
        height: 28px;
        font-size: 0.8rem;
    }

    .contact-cards {
        grid-template-columns: 1fr;
    }

    .topics-grid, .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .topics-grid, .features-grid {
        grid-template-columns: 1fr;
    }
}

/* ===== ANIMATIONS ===== */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(16px); }
    to { opacity: 1; transform: translateY(0); }
}

.help-section {
    animation: fadeIn 0.5s ease forwards;
}

.help-section:nth-child(2) { animation-delay: 0.05s; }
.help-section:nth-child(3) { animation-delay: 0.1s; }
.help-section:nth-child(4) { animation-delay: 0.15s; }
.help-section:nth-child(5) { animation-delay: 0.2s; }
.help-section:nth-child(6) { animation-delay: 0.25s; }
.help-section:nth-child(7) { animation-delay: 0.3s; }
.help-section:nth-child(8) { animation-delay: 0.35s; }

/* ===== PRINT ===== */
@media print {
    .header, .hero, .quick-nav, .back-to-top, .footer {
        display: none;
    }

    .main-content {
        padding: 0;
    }

    .help-section {
        box-shadow: none;
        border: 1px solid #ddd;
        page-break-inside: avoid;
    }

    .collapsible-content {
        max-height: none !important;
        padding: 16px 18px !important;
    }
}