/* ==========================================================================
   ChitraHub Complete Unified App UI Design System (Astra Compatible)
   ========================================================================== */

#chitrahub-quiz-app {
    --ch-blue-primary: #1254E6;
    --ch-blue-dark: #0D3EAC;
    --ch-blue-light: #EEF4FF;
    --ch-navy-bg: #0B1938;
    --ch-text-dark: #0F172A;
    --ch-text-muted: #64748B;
    --ch-orange: #ED5B2D;
    --ch-gold: #F59E0B;
    --ch-green: #10B981;
    --ch-red: #EF4444;
    --ch-border: #E2E8F0;
    --ch-radius-lg: 20px;
    --ch-radius-md: 12px;
    --ch-radius-full: 9999px;

    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--ch-text-dark);
    background-color: #F8FAFC;
    padding: 0;
    margin: 0 auto;
    max-width: 1360px;
    box-sizing: border-box;
    line-height: 1.5;
    position: relative;
}

#chitrahub-quiz-app * {
    box-sizing: border-box;
}

/* 1. Top Ribbon */
.ch-top-ribbon {
    background: #0E3CD4;
    color: #FFFFFF;
    padding: 8px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: var(--ch-radius-md) var(--ch-radius-md) 0 0;
}

.ch-top-ribbon-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.ch-badge-engine {
    background: #092AA4;
    color: #FCD34D;
    padding: 3px 10px;
    border-radius: var(--ch-radius-full);
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-weight: 800;
    font-size: 0.72rem;
    letter-spacing: 0.5px;
}

.ch-top-ribbon-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.ch-top-ribbon-right a {
    color: #FFF;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.ch-badge-plugin-zip {
    background: #FFF;
    color: #0E3CD4 !important;
    padding: 3px 12px;
    border-radius: var(--ch-radius-full);
    font-weight: 700;
}

/* 2. Main Navbar & Dropdowns */
.ch-navbar {
    background: #FFFFFF;
    border-bottom: 1px solid var(--ch-border);
    padding: 12px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    position: relative;
    z-index: 100;
}

.ch-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
}

.ch-brand-logo-icon {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background: #1254E6;
    color: #FFF;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    font-size: 1.25rem;
}

.ch-brand-text h1 {
    font-size: 1.25rem;
    font-weight: 900;
    color: #0F172A;
    margin: 0;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    line-height: 1.1;
}

.ch-brand-quiz-pill {
    border: 1.5px solid #1254E6;
    color: #1254E6;
    font-size: 0.65rem;
    padding: 1px 6px;
    border-radius: var(--ch-radius-full);
    font-weight: 800;
}

.ch-brand-text p {
    margin: 0;
    font-size: 0.72rem;
    color: var(--ch-text-muted);
}

.ch-nav-menu {
    display: flex;
    align-items: center;
    gap: 8px;
}

.ch-dropdown-wrapper {
    position: relative;
}

.ch-nav-pill-btn {
    border: 1px solid transparent;
    background: transparent;
    color: #334155;
    padding: 7px 14px;
    border-radius: var(--ch-radius-full);
    font-size: 0.86rem;
    font-weight: 700;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: all 0.2s;
}

.ch-nav-pill-btn:hover {
    background: #F1F5F9;
}

.ch-nav-pill-btn.active {
    background: var(--ch-blue-primary);
    color: #FFF;
}

.ch-dropdown-menu {
    position: absolute;
    top: calc(100% + 8px);
    left: 0;
    background: #FFFFFF;
    border: 1px solid #E2E8F0;
    border-radius: 14px;
    box-shadow: 0 14px 34px rgba(15, 23, 42, 0.12);
    min-width: 260px;
    padding: 8px;
    z-index: 1000;
    display: none;
}

.ch-dropdown-menu.show {
    display: block;
    animation: ch-dropdown-fade 0.15s ease-out;
}

@keyframes ch-dropdown-fade {
    from { opacity: 0; transform: translateY(-6px); }
    to { opacity: 1; transform: translateY(0); }
}

.ch-dropdown-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.15s;
    text-decoration: none !important;
}

.ch-dropdown-item:hover {
    background: #F8FAFC;
}

.ch-dropdown-item-left {
    display: flex;
    align-items: center;
    gap: 10px;
}

.ch-dropdown-item-title {
    font-size: 0.88rem;
    font-weight: 800;
    color: #0F172A;
    margin: 0;
}

.ch-dropdown-item-sub {
    font-size: 0.72rem;
    color: #64748B;
    margin: 0;
}

.ch-dropdown-tag {
    font-size: 0.65rem;
    font-weight: 800;
    padding: 2px 7px;
    border-radius: 4px;
    text-transform: uppercase;
}

.ch-tag-fast { background: #FEF9C3; color: #854D0E; }
.ch-tag-1v1 { background: #EFF6FF; color: #1E40AF; }
.ch-tag-xp { background: #FEF3C7; color: #D97706; }
.ch-tag-prize { background: #DCFCE7; color: #166534; }

.ch-nav-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.ch-idcard-pill {
    background: #FEF9C3;
    border: 1px solid #FDE047;
    padding: 4px 10px;
    border-radius: var(--ch-radius-full);
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 0.72rem;
    font-weight: 800;
    color: #713F12;
    cursor: pointer;
}

.ch-user-btn {
    background: #F8FAFC;
    border: 1px solid var(--ch-border);
    padding: 6px 12px;
    border-radius: var(--ch-radius-full);
    font-size: 0.85rem;
    font-weight: 700;
    color: #1E293B;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

/* 3. Hero Section */
.ch-hero-section {
    background: linear-gradient(135deg, #1254E6 0%, #0A3AC4 100%);
    border-radius: var(--ch-radius-lg);
    padding: 48px 42px;
    margin: 20px 24px;
    position: relative;
    overflow: hidden;
    color: #FFF;
}

.ch-hero-watermark {
    position: absolute;
    right: 28px;
    bottom: -32px;
    font-size: 10rem;
    font-weight: 900;
    color: rgba(255, 255, 255, 0.08);
    pointer-events: none;
    letter-spacing: -4px;
}

.ch-hero-arena-badge {
    background: rgba(0, 0, 0, 0.22);
    color: #FDE047;
    padding: 4px 12px;
    border-radius: var(--ch-radius-full);
    font-size: 0.75rem;
    font-weight: 800;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 16px;
}

.ch-hero-title {
    font-size: 2.5rem;
    font-weight: 900;
    line-height: 1.15;
    margin: 0 0 14px 0;
    max-width: 650px;
    color: #FFF !important;
}

.ch-hero-subtitle {
    font-size: 1rem;
    color: #E0E7FF;
    max-width: 580px;
    line-height: 1.5;
    margin: 0 0 28px 0;
}

.ch-hero-buttons-row {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-bottom: 14px;
}

.ch-btn-white {
    background: #FFFFFF;
    color: #1254E6 !important;
    padding: 12px 24px;
    border-radius: var(--ch-radius-full);
    font-weight: 800;
    font-size: 0.92rem;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: transform 0.2s;
}

.ch-btn-gold {
    background: #FBBF24;
    color: #0F172A !important;
    padding: 12px 22px;
    border-radius: var(--ch-radius-full);
    font-weight: 800;
    font-size: 0.92rem;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.ch-btn-glass {
    background: rgba(255, 255, 255, 0.16);
    color: #FFF !important;
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 10px 20px;
    border-radius: var(--ch-radius-full);
    font-weight: 700;
    font-size: 0.88rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.ch-btn-white:hover, .ch-btn-gold:hover, .ch-btn-glass:hover {
    transform: translateY(-2px);
}

/* 4. Daily Mission Bar */
.ch-daily-mission-bar {
    background: linear-gradient(90deg, #F97316 0%, #EA580C 100%);
    border-radius: var(--ch-radius-md);
    padding: 12px 24px;
    margin: 0 24px 24px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: #FFF;
    flex-wrap: wrap;
    gap: 12px;
}

.ch-daily-mission-left {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 700;
    font-size: 0.95rem;
}

.ch-mission-pill {
    background: #FFF;
    color: #EA580C;
    padding: 2px 10px;
    border-radius: var(--ch-radius-full);
    font-size: 0.72rem;
    font-weight: 900;
    text-transform: uppercase;
}

.ch-btn-solve-today {
    background: #FFF;
    color: #EA580C;
    font-weight: 800;
    font-size: 0.85rem;
    padding: 8px 18px;
    border-radius: var(--ch-radius-full);
    border: none;
    cursor: pointer;
}

/* 5. Metrics 4-Grid */
.ch-metrics-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin: 0 24px 24px 24px;
}

.ch-metric-card {
    background: #FFF;
    border: 1px solid var(--ch-border);
    border-radius: var(--ch-radius-md);
    padding: 18px 20px;
    display: flex;
    align-items: center;
    gap: 14px;
}

.ch-metric-icon-box {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.35rem;
}

.ch-metric-val {
    font-size: 1.5rem;
    font-weight: 900;
    color: #0F172A;
    line-height: 1.1;
}

.ch-metric-lbl {
    font-size: 0.7rem;
    color: var(--ch-text-muted);
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 2px;
}

/* 6. Feature 3-Grid */
.ch-features-grid {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 16px;
    margin: 0 24px 24px 24px;
}

.ch-feat-card {
    background: #FFF;
    border: 1px solid var(--ch-border);
    border-radius: var(--ch-radius-md);
    padding: 24px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.ch-feat-card.dark {
    background: #0E1E45;
    color: #FFF;
    border-color: #0E1E45;
}

.ch-feat-pill {
    font-size: 0.68rem;
    font-weight: 800;
    text-transform: uppercase;
    padding: 3px 8px;
    border-radius: var(--ch-radius-full);
    display: inline-block;
    margin-bottom: 10px;
    width: fit-content;
}

.ch-feat-pill.blue { background: #DBEAFE; color: #1E40AF; }
.ch-feat-pill.yellow { background: #FEF08A; color: #854D0E; }

.ch-feat-title {
    font-size: 1.1rem;
    font-weight: 800;
    margin: 0 0 6px 0;
    color: #0F172A;
}

.ch-feat-card.dark .ch-feat-title {
    color: #FFF;
}

.ch-feat-desc {
    font-size: 0.85rem;
    color: var(--ch-text-muted);
    line-height: 1.45;
    margin-bottom: 16px;
}

.ch-feat-card.dark .ch-feat-desc {
    color: #94A3B8;
}

.ch-feat-link {
    font-size: 0.85rem;
    font-weight: 800;
    color: var(--ch-blue-primary);
    text-decoration: none;
    cursor: pointer;
}

.ch-feat-card.dark .ch-feat-link {
    color: #FACC15;
}

/* 7. Rules Box */
.ch-rules-card {
    background: #FFF;
    border: 1px solid var(--ch-border);
    border-radius: var(--ch-radius-md);
    padding: 24px;
    margin: 0 24px 36px 24px;
}

.ch-rules-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 8px;
}

.ch-rules-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 14px;
}

.ch-rule-mini-box {
    background: #F8FAFC;
    border: 1px solid #EDF2F7;
    border-radius: var(--ch-radius-md);
    padding: 16px;
}

.ch-rule-header {
    font-size: 0.72rem;
    font-weight: 800;
    color: var(--ch-text-muted);
    text-transform: uppercase;
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 6px;
}

.ch-rule-main {
    font-size: 1.15rem;
    font-weight: 900;
    color: #0F172A;
    margin-bottom: 4px;
}

.ch-rule-desc {
    font-size: 0.76rem;
    color: #64748B;
    line-height: 1.4;
}

/* 8. Chapters Section */
.ch-curriculum-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 36px 24px 16px 24px;
    flex-wrap: wrap;
    gap: 12px;
}

.ch-curriculum-badge {
    background: #EEF4FF;
    color: #1E40AF;
    font-size: 0.72rem;
    font-weight: 800;
    padding: 4px 12px;
    border-radius: var(--ch-radius-full);
    display: inline-flex;
    align-items: center;
    gap: 6px;
    text-transform: uppercase;
}

.ch-curriculum-title {
    font-size: 1.8rem;
    font-weight: 900;
    color: #0F172A;
    margin: 8px 0 4px 0;
}

.ch-filters-bar {
    display: flex;
    gap: 8px;
    margin: 16px 24px 24px 24px;
    flex-wrap: wrap;
}

.ch-filter-pill {
    background: #FFF;
    border: 1px solid var(--ch-border);
    padding: 7px 18px;
    border-radius: var(--ch-radius-full);
    font-size: 0.85rem;
    font-weight: 700;
    color: #475569;
    cursor: pointer;
}

.ch-filter-pill.active {
    background: #1254E6;
    color: #FFF;
    border-color: #1254E6;
}

.ch-chapters-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin: 0 24px 36px 24px;
}

.ch-chapter-card {
    background: #FFF;
    border: 1px solid var(--ch-border);
    border-radius: var(--ch-radius-md);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    box-shadow: 0 2px 8px rgba(0,0,0,0.03);
}

.ch-chapter-card-cover {
    height: 180px;
    position: relative;
    background-size: cover;
    background-position: center;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 14px;
}

.ch-chapter-card-cover::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(0,0,0,0.3) 0%, rgba(0,0,0,0.85) 100%);
}

.ch-cover-badges {
    position: relative;
    z-index: 2;
    display: flex;
    justify-content: space-between;
}

.ch-cover-title-group {
    position: relative;
    z-index: 2;
}

.ch-chapter-art-title {
    color: #FFF;
    font-size: 1.15rem;
    font-weight: 900;
    margin: 0;
}

.ch-chapter-art-subtitle {
    color: #E2E8F0;
    font-size: 0.78rem;
    margin-top: 3px;
}

.ch-chapter-body {
    padding: 16px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.ch-chapter-desc {
    font-size: 0.85rem;
    color: var(--ch-text-muted);
    line-height: 1.45;
    margin-bottom: 16px;
}

.ch-chapter-meta-row {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.78rem;
    font-weight: 700;
    color: #475569;
    margin-bottom: 14px;
}

.ch-btn-start-chapter {
    background: #1254E6;
    color: #FFF;
    font-weight: 800;
    font-size: 0.9rem;
    padding: 11px;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

/* Badges */
.ch-badge-ch { background: #1254E6; color: #FFF; font-size: 0.65rem; font-weight: 800; padding: 3px 8px; border-radius: var(--ch-radius-full); }
.ch-badge-diff-easy { background: #10B981; color: #FFF; font-size: 0.65rem; font-weight: 800; padding: 3px 8px; border-radius: var(--ch-radius-full); }
.ch-badge-diff-medium { background: #F59E0B; color: #FFF; font-size: 0.65rem; font-weight: 800; padding: 3px 8px; border-radius: var(--ch-radius-full); }
.ch-badge-diff-hard { background: #EF4444; color: #FFF; font-size: 0.65rem; font-weight: 800; padding: 3px 8px; border-radius: var(--ch-radius-full); }
.ch-badge-pro { background: #F59E0B; color: #FFF; font-size: 0.65rem; font-weight: 800; padding: 3px 8px; border-radius: var(--ch-radius-full); display: inline-flex; align-items: center; gap: 3px; }

/* 9. Standalone Modals (ID Card, Daily Quiz Fact) */
.ch-modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.75);
    backdrop-filter: blur(4px);
    z-index: 99999;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.ch-modal-box {
    background: #0B1938;
    color: #FFF;
    border-radius: 20px;
    max-width: 680px;
    width: 100%;
    padding: 24px;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.35);
    position: relative;
    max-height: 90vh;
    overflow-y: auto;
}

.ch-modal-box.light {
    background: #FFF;
    color: #0F172A;
}

/* Scholar ID Card Component */
.ch-idcard-graphic {
    background: #1E293B;
    border: 2px solid #F59E0B;
    border-radius: 16px;
    padding: 24px;
    margin: 16px 0;
    color: #FFF;
    position: relative;
}

.ch-idcard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px dashed rgba(255,255,255,0.2);
    padding-bottom: 12px;
    margin-bottom: 16px;
}

.ch-idcard-body {
    display: flex;
    gap: 20px;
}

.ch-idcard-photo {
    width: 100px;
    height: 120px;
    border-radius: 10px;
    object-fit: cover;
    border: 2px solid #F59E0B;
}

.ch-barcode-line {
    font-family: monospace;
    letter-spacing: 4px;
    font-size: 1.2rem;
    margin-top: 14px;
    border-top: 1px dashed rgba(255,255,255,0.2);
    padding-top: 10px;
}

/* 10. Rapid Fire Arena & 1v1 Arena */
.ch-arena-card-modal {
    background: #FFFFFF;
    border: 1px solid #E2E8F0;
    border-radius: 20px;
    padding: 42px 36px;
    max-width: 660px;
    margin: 36px auto;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.04);
}

.ch-arena-icon-bolt {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    background: #F97316;
    color: #FFF;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 2.2rem;
    margin-bottom: 16px;
}

.ch-arena-pill-badge {
    background: #FFF7ED;
    color: #EA580C;
    border: 1px solid #FFEDD5;
    font-size: 0.75rem;
    font-weight: 800;
    padding: 4px 12px;
    border-radius: 9999px;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 12px;
}

.ch-arena-main-title {
    font-size: 1.85rem;
    font-weight: 900;
    color: #0F172A;
    margin: 0 0 10px 0;
}

.ch-arena-subtitle {
    font-size: 0.92rem;
    color: #64748B;
    line-height: 1.5;
    max-width: 520px;
    margin: 0 auto 24px auto;
}

.ch-arena-stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
    margin-bottom: 28px;
}

.ch-arena-stat-box {
    border-radius: 12px;
    padding: 14px 10px;
    text-align: center;
}

.ch-stat-box-blue { background: #EFF6FF; }
.ch-stat-box-yellow { background: #FEF9C3; }
.ch-stat-box-purple { background: #FAF5FF; }

.ch-arena-stat-val {
    font-size: 1.35rem;
    font-weight: 900;
    color: #0F172A;
}

.ch-arena-stat-lbl {
    font-size: 0.68rem;
    font-weight: 800;
    color: #64748B;
    text-transform: uppercase;
}

/* 2x2 Option Buttons */
.ch-rf-options-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.ch-rf-opt-btn {
    background: #FFF;
    border: 2px solid #E2E8F0;
    border-radius: 12px;
    padding: 14px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 800;
    color: #1E293B;
    transition: all 0.15s;
    text-align: left;
}

.ch-rf-opt-btn:hover {
    border-color: #1254E6;
    background: #F8FAFC;
}

/* 11. Footer */
.ch-app-footer {
    border-top: 1px solid #E2E8F0;
    padding: 20px 24px;
    margin-top: 36px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    color: #64748B;
    flex-wrap: wrap;
    gap: 10px;
}

.ch-app-footer-left strong {
    color: #1254E6;
}

.ch-app-footer-right a {
    color: #64748B;
    text-decoration: none;
    margin-left: 8px;
}

/* ==========================================================================
   Scholar Sign In & Account Hub Modal (Pixel-Perfect)
   ========================================================================== */

.ch-account-hub-box {
    background: #FFFFFF;
    border-radius: 20px;
    max-width: 620px;
    width: 100%;
    padding: 28px 32px;
    box-shadow: 0 25px 60px rgba(15, 23, 42, 0.25);
    position: relative;
    max-height: 90vh;
    overflow-y: auto;
}

.ch-hub-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 20px;
}

.ch-hub-header-left {
    display: flex;
    align-items: center;
    gap: 14px;
}

.ch-hub-icon-square {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    background: #0284C7;
    color: #FFF;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
}

.ch-hub-title {
    font-size: 1.25rem;
    font-weight: 900;
    color: #0F172A;
    margin: 0;
}

.ch-hub-sub {
    font-size: 0.8rem;
    color: #64748B;
    margin: 2px 0 0 0;
}

.ch-hub-close {
    background: transparent;
    border: none;
    font-size: 1.4rem;
    color: #94A3B8;
    cursor: pointer;
    line-height: 1;
}

.ch-hub-tabs-row {
    display: flex;
    background: #F1F5F9;
    padding: 4px;
    border-radius: var(--ch-radius-full);
    margin-bottom: 20px;
}

.ch-hub-tab-btn {
    flex: 1;
    border: none;
    background: transparent;
    padding: 8px 16px;
    font-size: 0.85rem;
    font-weight: 700;
    color: #64748B;
    border-radius: var(--ch-radius-full);
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.ch-hub-tab-btn.active {
    background: #FFFFFF;
    color: #0F172A;
    box-shadow: 0 2px 6px rgba(0,0,0,0.06);
}

.ch-hub-helper-text {
    font-size: 0.78rem;
    color: #64748B;
    margin: 0 0 16px 0;
    line-height: 1.4;
}

.ch-hub-profiles-stack {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.ch-profile-switch-card {
    border: 1.5px solid #E2E8F0;
    border-radius: 14px;
    padding: 14px 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: #FFFFFF;
    transition: all 0.2s;
}

.ch-profile-switch-card.active {
    border-color: #0284C7;
    background: #F0F9FF;
}

.ch-profile-card-left {
    display: flex;
    align-items: center;
    gap: 14px;
}

.ch-profile-card-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid #E2E8F0;
}

.ch-profile-switch-card.active .ch-profile-card-avatar {
    border-color: #0284C7;
}

.ch-profile-name-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.ch-profile-card-name {
    font-size: 0.98rem;
    font-weight: 800;
    color: #0F172A;
    margin: 0;
}

.ch-pass-badge {
    font-size: 0.65rem;
    font-weight: 800;
    padding: 2px 6px;
    border-radius: 4px;
    text-transform: uppercase;
}

.ch-pass-free { background: #E0F2FE; color: #0369A1; }
.ch-pass-pro { background: #DBEAFE; color: #1D4ED8; }
.ch-pass-master { background: #FEF3C7; color: #B45309; }

.ch-profile-institution {
    font-size: 0.75rem;
    color: #64748B;
    margin: 2px 0 4px 0;
}

.ch-profile-meta-row {
    font-size: 0.72rem;
    font-weight: 700;
    color: #0284C7;
    display: flex;
    gap: 6px;
}

.ch-btn-switch-profile {
    background: #F8FAFC;
    border: 1px solid #CBD5E1;
    color: #0F172A;
    padding: 6px 16px;
    border-radius: var(--ch-radius-full);
    font-weight: 700;
    font-size: 0.8rem;
    cursor: pointer;
    transition: background 0.2s;
}

.ch-btn-switch-profile:hover {
    background: #E2E8F0;
}

.ch-badge-active-profile {
    background: #ECFDF5;
    border: 1px solid #A7F3D0;
    color: #059669;
    padding: 5px 14px;
    border-radius: var(--ch-radius-full);
    font-weight: 800;
    font-size: 0.8rem;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

/* Responsive */
@media (max-width: 1024px) {
    .ch-metrics-grid, .ch-rules-grid { grid-template-columns: repeat(2, 1fr); }
    .ch-chapters-grid, .ch-features-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
    .ch-metrics-grid, .ch-rules-grid { grid-template-columns: 1fr; }
    .ch-hero-section { padding: 24px; }
    .ch-hero-title { font-size: 1.8rem; }
}