:root{--ncert-blue:#1d4ed8;--ncert-blue-dark:#1e40af;--ncert-blue-mid:#2563eb;--ncert-blue-pale:#eff6ff;--ncert-blue-border:#bfdbfe;--ncert-explainer-bg:#eff6ff;--ncert-explainer-border:#3b82f6;--ncert-explainer-text:#1e40af;--ncert-bridge-bg:#fffbeb;--ncert-bridge-border:#f59e0b;--ncert-bridge-text:#92400e;--ncert-upsc-bg:#f0fdf4;--ncert-upsc-border:#22c55e;--ncert-upsc-text:#14532d;--ncert-fact-bg:#fefce8;--ncert-fact-border:#eab308;--ncert-fact-text:#713f12}.ncert-header{background:linear-gradient(135deg,#1e3a8a 0,#1d4ed8 60%,#2563eb 100%);color:#fff;padding:var(--space-10) 0 var(--space-8)}.ncert-header .breadcrumb a{color:rgba(255,255,255,.75)}.ncert-header .breadcrumb a:hover{color:#fff}.ncert-header .breadcrumb__sep{color:rgba(255,255,255,.4)}.ncert-header__meta{display:flex;align-items:center;gap:var(--space-2);flex-wrap:wrap;margin-bottom:var(--space-4)}.ncert-gs-badge{display:inline-flex;align-items:center;padding:3px 10px;border-radius:var(--radius-sm);font-size:var(--text-xs);font-weight:var(--font-bold);text-transform:uppercase;letter-spacing:.06em;background:rgba(255,255,255,.18);border:1px solid rgba(255,255,255,.35);color:#fff}.ncert-class-badge{display:inline-flex;align-items:center;gap:var(--space-2);background:rgba(255,255,255,.15);border:1px solid rgba(255,255,255,.3);border-radius:var(--radius-full);padding:var(--space-1) var(--space-4);font-size:var(--text-xs);font-weight:var(--font-semibold);letter-spacing:.06em;text-transform:uppercase;color:rgba(255,255,255,.9);margin-bottom:0}.ncert-chapter-number{font-family:var(--font-body);font-size:var(--text-xs);font-weight:var(--font-bold);letter-spacing:.1em;text-transform:uppercase;color:rgba(255,255,255,.6);margin-bottom:var(--space-2)}.ncert-header h1{font-family:var(--font-heading);font-size:clamp(1.5rem, 4vw, 2.25rem);font-weight:var(--font-bold);color:#fff;line-height:var(--leading-tight);margin-bottom:var(--space-3)}.ncert-header__subtitle{font-size:var(--text-base);color:rgba(255,255,255,.8);line-height:var(--leading-relaxed);max-width:680px}.ncert-book-tag{display:inline-flex;align-items:center;gap:var(--space-2);background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.2);border-radius:var(--radius-md);padding:var(--space-2) var(--space-3);font-size:var(--text-xs);color:rgba(255,255,255,.85);margin-top:var(--space-4)}.ncert-article{font-size:var(--text-base);line-height:var(--leading-relaxed);color:var(--color-text)}.ncert-article h2{font-family:var(--font-heading);font-size:var(--text-xl);font-weight:var(--font-bold);color:var(--ncert-blue-dark);margin-top:var(--space-10);margin-bottom:var(--space-4);padding-bottom:var(--space-3);border-bottom:2px solid var(--ncert-blue-border)}.ncert-article h3{font-size:var(--text-lg);font-weight:var(--font-semibold);color:var(--ncert-blue-dark);margin-top:var(--space-6);margin-bottom:var(--space-3)}.ncert-article h4{font-size:var(--text-sm);font-weight:var(--font-semibold);color:var(--ncert-blue-mid);text-transform:uppercase;letter-spacing:.04em;margin-top:var(--space-4);margin-bottom:var(--space-1)}.ncert-article .table-scroll{border-radius:var(--radius-lg);overflow:hidden;border:1px solid var(--color-border-light);box-shadow:0 2px 6px rgba(0,0,0,.05);margin:var(--space-5) 0;position:relative}.ncert-article .table-scroll-inner{overflow-x:auto;-webkit-overflow-scrolling:touch}.ncert-article table{border-collapse:collapse;border-spacing:0;width:100%;font-size:var(--text-sm);border:none;box-shadow:none;border-radius:0;margin:0;background:#fff}.ncert-article th{background:#1e293b;color:#f1f5f9;padding:11px var(--space-4);text-align:left;font-weight:var(--font-semibold);font-size:var(--text-xs);letter-spacing:.07em;text-transform:uppercase;white-space:normal;border:none}.ncert-article td{padding:11px var(--space-4);border-bottom:1px solid var(--color-border-light);color:var(--color-text);line-height:1.65;vertical-align:top;font-size:var(--text-sm);background:#fff}.ncert-article td:first-child{font-weight:var(--font-semibold);color:var(--color-text);background:#fff}.ncert-article tr:last-child td{border-bottom:none}.ncert-article tr:nth-child(2n) td{background:rgba(30,41,59,.02)}.ncert-article tr:hover td{background:rgba(30,41,59,.04)}.ncert-box__body .table-scroll{border-color:rgba(0,0,0,.1);box-shadow:none;margin-top:var(--space-4)}.ncert-box--explainer .ncert-box__body th{background:#1e3a5f}.ncert-box--bridge .ncert-box__body th{background:#78350f}.ncert-box--upsc .ncert-box__body th{background:#14532d}.ncert-box--fact .ncert-box__body th{background:#713f12}.ncert-box--explainer .ncert-box__body td{border-bottom-color:rgba(59,130,246,.15)}.ncert-box--bridge .ncert-box__body td{border-bottom-color:rgba(245,158,11,.15)}.ncert-box--upsc .ncert-box__body td{border-bottom-color:rgba(34,197,94,.15)}.ncert-box--fact .ncert-box__body td{border-bottom-color:rgba(234,179,8,.18)}.ncert-box--bridge .ncert-box__body td:first-child,.ncert-box--explainer .ncert-box__body td:first-child,.ncert-box--fact .ncert-box__body td:first-child,.ncert-box--upsc .ncert-box__body td:first-child{background:0 0;border-right:none}.ncert-box--explainer .ncert-box__body tr:hover td{background:rgba(59,130,246,.05)}.ncert-box--bridge .ncert-box__body tr:hover td{background:rgba(245,158,11,.05)}.ncert-box--upsc .ncert-box__body tr:hover td{background:rgba(34,197,94,.05)}.ncert-box--fact .ncert-box__body tr:hover td{background:rgba(234,179,8,.05)}.ncert-article td.ncert-num-col{background:#fff!important;border-right:none!important;font-weight:var(--font-normal)!important;text-align:center;color:var(--color-text-muted);width:2.5rem;min-width:2.5rem}.ncert-box--explainer{background:var(--ncert-explainer-bg);border-left:4px solid var(--ncert-explainer-border);border-radius:0 var(--radius-md) var(--radius-md) 0;padding:var(--space-5) var(--space-6);margin:var(--space-6) 0}.ncert-box--explainer .ncert-box__title{color:var(--ncert-explainer-text);font-size:var(--text-sm);font-weight:var(--font-bold);text-transform:uppercase;letter-spacing:.06em;margin-bottom:var(--space-3);display:flex;align-items:center;gap:var(--space-2)}.ncert-box--explainer .ncert-box__title::before{content:"💡";font-style:normal;font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif}.ncert-box--bridge{background:var(--ncert-bridge-bg);border-left:4px solid var(--ncert-bridge-border);border-radius:0 var(--radius-md) var(--radius-md) 0;padding:var(--space-5) var(--space-6);margin:var(--space-6) 0}.ncert-box--bridge .ncert-box__title{color:var(--ncert-bridge-text);font-size:var(--text-sm);font-weight:var(--font-bold);text-transform:uppercase;letter-spacing:.06em;margin-bottom:var(--space-3);display:flex;align-items:center;gap:var(--space-2)}.ncert-box--bridge .ncert-box__title::before{content:"🔗";font-style:normal;font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif}.ncert-box--upsc{background:var(--ncert-upsc-bg);border:1px solid var(--ncert-upsc-border);border-left:4px solid var(--ncert-upsc-border);border-radius:0 var(--radius-md) var(--radius-md) 0;padding:var(--space-5) var(--space-6);margin:var(--space-6) 0}.ncert-box--upsc .ncert-box__title{color:var(--ncert-upsc-text);font-size:var(--text-sm);font-weight:var(--font-bold);text-transform:uppercase;letter-spacing:.06em;margin-bottom:var(--space-3);display:flex;align-items:center;gap:var(--space-2)}.ncert-box--upsc .ncert-box__title::before{content:"🎯";font-style:normal;font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif}.ncert-box--fact{background:var(--ncert-fact-bg);border-left:4px solid var(--ncert-fact-border);border-radius:0 var(--radius-md) var(--radius-md) 0;padding:var(--space-5) var(--space-6);margin:var(--space-6) 0}.ncert-box--fact .ncert-box__title{color:var(--ncert-fact-text);font-size:var(--text-sm);font-weight:var(--font-bold);text-transform:uppercase;letter-spacing:.06em;margin-bottom:var(--space-3);display:flex;align-items:center;gap:var(--space-2)}.ncert-box--fact .ncert-box__title::before{content:"📌";font-style:normal;font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif}.ncert-box__body{font-size:var(--text-sm);line-height:var(--leading-relaxed);color:var(--color-text)}.ncert-box__body ol:last-child,.ncert-box__body p:last-child,.ncert-box__body ul:last-child{margin-bottom:0}.ncert-book-info-card{background:var(--ncert-blue-pale);border:1px solid var(--ncert-blue-border);border-radius:var(--radius-lg);padding:var(--space-5);margin-bottom:var(--space-5)}.ncert-book-info-card__label{font-size:var(--text-xs);font-weight:var(--font-bold);text-transform:uppercase;letter-spacing:.06em;color:var(--ncert-blue);margin-bottom:var(--space-3)}.ncert-book-info-card__item{font-size:var(--text-xs);color:var(--color-text-secondary);margin-bottom:var(--space-2);display:grid;grid-template-columns:64px 1fr;gap:var(--space-2);align-items:baseline}.ncert-book-info-card__item strong{color:var(--color-text);font-weight:var(--font-semibold);flex-shrink:0}.ncert-book-info-card__item span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.ncert-header~section .topic-sidebar{top:60px}.ncert-hub-header{background:linear-gradient(135deg,#0f2d6b 0,#1d4ed8 100%);color:#fff;padding:var(--space-16) 0 var(--space-12);text-align:center}.ncert-hub-header h1{font-family:var(--font-heading);font-size:clamp(2rem, 5vw, 3rem);font-weight:var(--font-bold);color:#fff;margin-bottom:var(--space-4)}.ncert-hub-header p{font-size:var(--text-lg);color:rgba(255,255,255,.85);max-width:640px;margin:0 auto;line-height:var(--leading-relaxed)}.ncert-phase-badge{display:inline-block;background:rgba(255,255,255,.15);border:1px solid rgba(255,255,255,.3);border-radius:var(--radius-full);padding:var(--space-1) var(--space-5);font-size:var(--text-xs);font-weight:var(--font-semibold);letter-spacing:.08em;text-transform:uppercase;color:rgba(255,255,255,.9);margin-bottom:var(--space-5)}.ncert-class-section{padding:var(--space-12) 0}.ncert-class-section+.ncert-class-section{border-top:1px solid var(--color-border-light)}.ncert-class-heading{font-family:var(--font-heading);font-size:var(--text-2xl);font-weight:var(--font-bold);color:var(--ncert-blue-dark);margin-bottom:var(--space-2)}.ncert-class-desc{font-size:var(--text-base);color:var(--color-text-secondary);margin-bottom:var(--space-8)}.ncert-book-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:var(--space-5)}.ncert-book-card{background:var(--color-surface);border:1px solid var(--color-border);border-top:3px solid var(--ncert-blue);border-radius:var(--radius-lg);padding:var(--space-6);text-decoration:none;color:var(--color-text);transition:box-shadow var(--transition-normal),transform var(--transition-normal);display:flex;flex-direction:column;gap:var(--space-3)}.ncert-book-card:hover{box-shadow:var(--shadow-card-hover);transform:translateY(-2px);border-top-color:var(--ncert-blue-mid)}.ncert-book-card__subject{font-size:var(--text-xs);font-weight:var(--font-semibold);text-transform:uppercase;letter-spacing:.06em;color:var(--ncert-blue)}.ncert-book-card__title{font-family:var(--font-heading);font-size:var(--text-lg);font-weight:var(--font-bold);color:var(--color-brand);line-height:var(--leading-snug)}.ncert-book-card__meta{font-size:var(--text-xs);color:var(--color-text-muted);display:flex;gap:var(--space-3);align-items:center}.ncert-book-card__chapters{font-size:var(--text-xs);font-weight:var(--font-semibold);color:var(--ncert-blue);margin-top:auto;padding-top:var(--space-3);border-top:1px solid var(--color-border-light)}.ncert-chapter-list{list-style:none;padding:0;margin:0}.ncert-chapter-list__item{border-bottom:1px solid var(--color-border-light)}.ncert-chapter-list__item:last-child{border-bottom:none}.ncert-chapter-list__link{display:flex;align-items:center;gap:var(--space-4);padding:var(--space-4) var(--space-3);text-decoration:none;color:var(--color-text);border-radius:var(--radius-md);transition:background var(--transition-fast)}.ncert-chapter-list__link:hover{background:var(--ncert-blue-pale);color:var(--ncert-blue-dark)}.ncert-chapter-list__num{min-width:2rem;height:2rem;background:var(--ncert-blue-pale);border:1px solid var(--ncert-blue-border);border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;font-size:var(--text-xs);font-weight:var(--font-bold);color:var(--ncert-blue);flex-shrink:0}.ncert-chapter-list__title{font-size:var(--text-base);font-weight:var(--font-medium);line-height:var(--leading-snug);flex:1}.ncert-chapter-list__arrow{color:var(--color-text-muted);font-size:var(--text-sm);flex-shrink:0}.ncert-toc .toc-list{list-style:none;padding:0;margin:0}.ncert-toc .toc-link{display:block;font-size:var(--text-xs);color:var(--color-text-secondary);text-decoration:none;padding:4px 0 4px var(--space-3);line-height:1.4;border-left:2px solid transparent;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;transition:color .12s,border-color .12s}.ncert-toc .toc-link:hover{color:var(--ncert-blue);border-left-color:var(--ncert-blue-border)}.ncert-toc .toc-link.toc-active{color:var(--ncert-blue)!important;font-weight:var(--font-semibold);border-left-color:var(--ncert-blue)}.ncert-toc .toc-item--part{margin-top:var(--space-3);padding-top:var(--space-2);border-top:1px solid var(--ncert-blue-border);counter-increment:none}.ncert-toc .toc-item--part:first-child{margin-top:0;padding-top:0;border-top:none}.ncert-toc .toc-link--part{padding-left:0;border-left:none!important;font-weight:var(--font-bold);color:var(--ncert-blue-dark);font-size:var(--text-xs);white-space:normal;line-height:1.3}.ncert-toc .toc-link--part::before{display:none!important}.ncert-toc .toc-link--part:hover{color:var(--ncert-blue-mid);border-left:none!important}.ncert-toc .toc-item--h2{margin-top:1px}.ncert-toc .toc-item--h3 .toc-link{padding-left:var(--space-5);color:var(--color-text-muted);font-size:calc(var(--text-xs) - .5px)}.ncert-article h2.ncert-part-divider{background:var(--ncert-blue-pale);border:1px solid var(--ncert-blue-border);border-left:4px solid var(--ncert-blue);border-bottom:1px solid var(--ncert-blue-border);border-radius:var(--radius-md);padding:var(--space-3) var(--space-5);margin-top:var(--space-12);font-size:var(--text-lg);letter-spacing:.01em}.ncert-article .table-scroll::after{content:'';position:absolute;top:0;right:0;width:48px;height:100%;background:linear-gradient(to right,transparent,rgba(255,255,255,.95));pointer-events:none;transition:opacity .2s}.ncert-article .table-scroll.ncert-table-scrolled::after{opacity:0}@media (max-width:768px){.ncert-article td,.ncert-article th{padding:9px var(--space-3)}.ncert-book-grid{grid-template-columns:1fr}.ncert-hub-header{padding:var(--space-10) 0 var(--space-8)}.ncert-class-section{padding:var(--space-8) 0}.ncert-box--bridge,.ncert-box--explainer,.ncert-box--fact,.ncert-box--upsc{padding:var(--space-4)}}