:root{--bg-a:#fff4e6;--bg-b:#fce7f3;--bg-c:#ecfccb;--surface:rgba(255,255,255,.92);--surface-strong:#ffffff;--text:#1f2937;--muted:#556273;--line:#d9e2ec;--primary:#2563eb;--primary-2:#7c3aed;--accent:#0f9f7f;--soft-blue:#edf6ff;--soft-purple:#f4efff;--soft-green:#ecfbf4;--lesson-scale:1;}*{box-sizing:border-box}html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}body{margin:0;min-height:100vh;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif;line-height:1.68;color:var(--text);background:radial-gradient(circle at 8% 8%,rgba(37,99,235,.12),transparent 28rem),radial-gradient(circle at 92% 18%,rgba(124,58,237,.10),transparent 30rem),linear-gradient(135deg,var(--bg-a) 0%,var(--bg-b) 48%,var(--bg-c) 100%);background-attachment:fixed;}body,button,input{font:inherit}img,svg,video,canvas{max-width:100%;height:auto}a{color:inherit}button,a{-webkit-tap-highlight-color:transparent}.skip-link{position:absolute;left:-9999px;top:8px;z-index:9999;background:#fff;padding:10px 14px;border-radius:8px}.skip-link:focus{left:8px}#readingProgress{position:fixed;top:0;left:0;height:4px;width:0;background:linear-gradient(90deg,var(--primary),var(--primary-2),var(--accent));z-index:10000;box-shadow:0 1px 8px rgba(37,99,235,.25)}.wrap{width:min(1480px,96%);margin:0 auto;padding:12px 0 42px}.top-badge-bar{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:9px 13px;margin-bottom:9px;background:linear-gradient(110deg,rgba(255,255,255,.96),rgba(238,247,255,.96),rgba(242,255,249,.96));border:1px solid rgba(203,213,225,.85);border-radius:14px;box-shadow:0 10px 30px rgba(67,88,120,.07);font-size:.88rem}.top-badge-bar p{margin:0;text-align:center;color:var(--muted)}.top-pill{font-weight:800;white-space:nowrap}.fa-graduation-cap:before{content:"🎓"}.fa-star:before{content:"★"}.site-header{position:relative;display:flex;align-items:center;gap:18px;justify-content:space-between;padding:10px 14px;margin-bottom:13px;background:var(--surface);border:1px solid rgba(203,213,225,.85);border-radius:16px;box-shadow:0 12px 34px rgba(56,78,112,.08);backdrop-filter:blur(10px)}.header-logo-row{flex:0 0 auto}.site-logo-link{display:flex;align-items:center;gap:8px;text-decoration:none}.site-logo-image img{display:block;width:150px;height:75px;object-fit:contain}.logo-tagline{font-weight:750;color:var(--muted)}.main-nav{min-width:0}.nav-links{display:flex;flex-wrap:wrap;gap:3px 8px;list-style:none;margin:0;padding:0;justify-content:flex-end}.nav-links a{display:block;padding:7px 6px;text-decoration:none;border-radius:9px;font-size:.9rem;transition:.15s ease}.nav-links a:hover,.nav-links a.active{background:linear-gradient(100deg,var(--soft-blue),var(--soft-purple));color:#153e75}.menu-toggle{display:none;border:1px solid #cbd5e1;background:linear-gradient(135deg,#fff,#eef7ff);border-radius:10px;padding:8px 11px;font-size:1.25rem;cursor:pointer}.sidebar-overlay,.sidebar{display:none}.t,.m{position:absolute;opacity:0;pointer-events:none}.t-btn{position:fixed;left:10px;bottom:10px;z-index:9000;padding:8px 11px;background:linear-gradient(135deg,#fff,#eef7ff,#f5efff);border:1px solid #cbd5e1;border-radius:999px;font-size:.82rem;cursor:pointer;box-shadow:0 5px 18px rgba(40,55,90,.13)}.m-btn,.ov{display:none}.lay{display:grid;grid-template-columns:minmax(240px,310px) minmax(0,1fr);gap:18px;align-items:start}.card{background:var(--surface);border:1px solid rgba(203,213,225,.86);border-radius:16px;overflow:hidden;box-shadow:0 12px 35px rgba(64,82,112,.07);backdrop-filter:blur(9px)}.card>.hd{padding:13px 15px;border-bottom:1px solid var(--line);background:linear-gradient(110deg,#f8fbff,#f5f1ff,#f2fbf6)}.card>.bd{padding:15px}.side{position:sticky;top:10px;max-height:calc(100vh - 20px);overflow:auto;overscroll-behavior:contain;overflow-anchor:none;scrollbar-gutter:stable}.side .hd{display:flex;justify-content:space-between;align-items:center}.side .hd h2{margin:0;font-size:1rem}.course-sidebar-close{display:none}.course-sidebar-tools{display:grid;grid-template-columns:1fr auto;gap:7px;margin-bottom:10px}.course-sidebar-tools label{grid-column:1/-1;font-size:.82rem;font-weight:700}.course-sidebar-tools input{min-width:0;width:100%;padding:9px 10px;border:1px solid #cbd5e1;border-radius:9px;background:#fff;color:#1f2937}.course-sidebar-tools button{padding:8px 10px;border:1px solid #cbd5e1;border-radius:9px;background:linear-gradient(135deg,#fff,#eef7ff);cursor:pointer}.search-empty{font-size:.85rem;color:var(--muted)}.course-list{list-style:none;margin:0;padding:0}.chapter-group{margin:0 0 4px}.chapter-group[hidden]{display:none}.chapter-group .link{display:flex;align-items:flex-start;gap:9px;padding:9px;text-decoration:none;border-radius:9px;transition:.15s ease}.chapter-group .link:hover{background:linear-gradient(100deg,var(--soft-blue),var(--soft-green))}.chapter-group.active-chapter .link{background:linear-gradient(105deg,#dceeff,#e8e1ff,#ddf7eb);font-weight:750;color:#173a67}.num{flex:0 0 auto;min-width:46px;font-weight:800;font-size:.82rem}.txt{display:flex;min-width:0;flex-direction:column}.txt b{font-size:.9rem}.txt em{margin-top:1px;color:var(--muted);font-size:.78rem;font-style:normal;overflow-wrap:anywhere}.course-content{min-width:0}.course-content .bd{font-size:calc(1rem * var(--lesson-scale));transition:font-size .15s ease}.breadcrumbs{display:flex;flex-wrap:wrap;gap:6px;align-items:center;margin:0 0 12px;font-size:.9rem;color:var(--muted)}.breadcrumbs a{text-decoration:none}.breadcrumbs a:hover{text-decoration:underline}.hero{position:relative;overflow:hidden;background:linear-gradient(125deg,#e8f5ff 0%,#eee8ff 52%,#e7f9ef 100%);border:1px solid #cdddeb;border-radius:16px;padding:23px;margin-bottom:14px}.hero:after{content:"";position:absolute;width:180px;height:180px;border-radius:50%;right:-70px;top:-90px;background:rgba(255,255,255,.48);pointer-events:none}.engc-title{position:relative;z-index:1;margin:0 0 8px;font-size:clamp(1.75rem,3vw,2.65rem);line-height:1.18}.sub{position:relative;z-index:1;margin:0 0 14px;color:#43546a}.meta{position:relative;z-index:1;display:flex;flex-wrap:wrap;gap:8px}.pill{display:inline-block;padding:7px 11px;border:1px solid #cbd5e1;border-radius:999px;background:rgba(255,255,255,.72);font-size:.88rem}.course-tools{display:flex;justify-content:space-between;gap:12px;align-items:center;flex-wrap:wrap;padding:10px 12px;margin-bottom:14px;border:1px solid #d3deea;border-radius:12px;background:linear-gradient(105deg,#f8fbff,#f7f2ff,#f3fcf7)}.reading-meta,.tool-actions{display:flex;align-items:center;gap:8px;flex-wrap:wrap}.tool-btn{border:1px solid #c8d5e3;background:linear-gradient(135deg,#fff,#edf6ff,#f5f0ff);border-radius:9px;padding:8px 11px;cursor:pointer;font-weight:650;transition:transform .12s ease,box-shadow .12s ease}.tool-btn:hover{transform:translateY(-1px);box-shadow:0 6px 15px rgba(55,75,110,.1)}.tool-btn:focus-visible,.menu-toggle:focus-visible,.t-btn:focus-visible,.chapter-nav a:focus-visible{outline:3px solid rgba(37,99,235,.28);outline-offset:2px}.chapter-nav{display:flex;justify-content:space-between;gap:12px;margin-top:22px;padding-top:16px;border-top:1px solid var(--line)}.chapter-nav a{text-decoration:none;font-weight:750;padding:10px 13px;border:1px solid #cbd5e1;border-radius:10px;background:linear-gradient(115deg,#fff,#edf6ff,#f2edff)}.course-sidebar-toggle{display:none}.ml-footer{margin-top:24px;padding:23px 16px;text-align:center;border:1px solid #cfdae6;border-radius:16px;background:linear-gradient(120deg,#f5fbff,#f6f1ff,#f1fbf5);box-shadow:0 10px 28px rgba(62,83,116,.06)}.ml-footer-social{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin-bottom:12px}.ml-footer-social a{display:inline-flex;align-items:center;justify-content:center;width:41px;height:41px;border:1px solid #cbd5e1;border-radius:50%;background:linear-gradient(135deg,#fff,#edf6ff,#f4efff);text-decoration:none;transition:transform .15s ease}.ml-footer-social a:hover{transform:translateY(-2px)}.ml-footer-social svg{width:20px;height:20px}.ml-copy{margin:0;color:var(--muted);font-size:.9rem}#goTopBtn{position:fixed;right:18px;bottom:18px;width:44px;height:44px;border:1px solid #cbd5e1;border-radius:50%;background:linear-gradient(135deg,#fff,#eaf5ff,#efeaff);font-size:1.2rem;cursor:pointer;box-shadow:0 8px 24px rgba(0,0,0,.12);opacity:0;pointer-events:none;transform:translateY(8px);transition:opacity .2s ease,transform .2s ease;z-index:8500}#goTopBtn.is-visible{opacity:1;pointer-events:auto;transform:none}body.chapter-loading .course-content{opacity:.58;pointer-events:none}body.dark-view{--surface:rgba(19,29,46,.95);--surface-strong:#172235;--text:#e8eef7;--muted:#b8c5d6;--line:#34445c;background:radial-gradient(circle at 10% 10%,rgba(40,101,174,.2),transparent 28rem),radial-gradient(circle at 90% 15%,rgba(107,67,164,.18),transparent 30rem),linear-gradient(135deg,#0c1421,#151426 48%,#0d201b);color:var(--text)}body.dark-view .card,body.dark-view .site-header{background:var(--surface);border-color:#34445c;color:var(--text)}body.dark-view .top-badge-bar,body.dark-view .hero,body.dark-view .course-tools,body.dark-view .ml-footer,body.dark-view .card>.hd{background:linear-gradient(120deg,#172638,#201b35,#162b25);border-color:#34445c;color:var(--text)}body.dark-view .sub,body.dark-view .txt em,body.dark-view .top-badge-bar p,body.dark-view .breadcrumbs,body.dark-view .ml-copy{color:#b8c5d6}body.dark-view .chapter-group .link:hover{background:linear-gradient(100deg,#21344b,#25382f)}body.dark-view .chapter-group.active-chapter .link{background:linear-gradient(105deg,#243b59,#382d55,#214238);color:#f5f8ff}body.dark-view .tool-btn,body.dark-view .course-sidebar-tools button,body.dark-view .course-sidebar-tools input,body.dark-view .t-btn,body.dark-view #goTopBtn,body.dark-view .ml-footer-social a,body.dark-view .chapter-nav a{background:linear-gradient(135deg,#172235,#1c2d43,#261f3d);color:#e8eef7;border-color:#455a75}body.dark-view .pill{background:rgba(20,31,49,.72);border-color:#455a75}body.dark-view .sidebar{background:#172235;color:#e8eef7}@media(max-width:1020px){.main-nav{display:none}.menu-toggle{display:block}.sidebar-overlay{display:block;position:fixed;inset:0;background:rgba(15,23,42,.54);z-index:9700;opacity:0;pointer-events:none;transition:opacity .2s ease}.sidebar{display:block;position:fixed;top:0;right:0;width:min(330px,88vw);height:100dvh;background:#fff;z-index:9800;transform:translateX(100%);transition:transform .22s ease;padding:18px;overflow:auto}.sidebar ul{list-style:none;padding:0;margin:40px 0 0}.sidebar a{display:block;padding:12px 8px;text-decoration:none;border-bottom:1px solid #e5e7eb}.close-btn{position:absolute;right:14px;top:12px;border:1px solid #d1d5db;background:#fff;border-radius:8px;padding:7px 10px;cursor:pointer}body.menu-open .sidebar{transform:none}body.menu-open .sidebar-overlay{opacity:1;pointer-events:auto}.top-badge-bar p{display:none}}@media(max-width:900px){.lay{grid-template-columns:1fr}.course-sidebar{position:fixed;top:0;left:0;width:min(360px,90vw);height:100dvh;max-height:none;z-index:9600;transform:translateX(-105%);transition:transform .22s ease;border-radius:0}.course-sidebar.is-open{transform:none}.course-sidebar-close{display:block;border:1px solid #d1d5db;background:#fff;border-radius:8px;padding:5px 8px;cursor:pointer}.course-sidebar-toggle{display:flex;align-items:center;justify-content:center;gap:8px;width:100%;margin:0 0 12px;padding:10px 12px;border:1px solid #cbd5e1;border-radius:10px;background:linear-gradient(135deg,#fff,#edf6ff);font:inherit;font-weight:750;cursor:pointer}.course-content{width:100%}.site-logo-image img{width:130px;height:65px}.logo-tagline{display:none}}@media(max-width:560px){.wrap{width:94%;padding-top:8px}.top-badge-bar{padding:7px 9px}.site-header{padding:8px 10px}.card>.bd{padding:11px}.hero{padding:17px}.chapter-nav{flex-wrap:wrap}.chapter-nav a{flex:1 1 145px;text-align:center}.engc-title{font-size:1.72rem}.course-tools{align-items:flex-start}.t-btn{font-size:.74rem}.ml-footer{padding:18px 10px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation-duration:.01ms!important;transition-duration:.01ms!important}}@media print{body{background:#fff!important;color:#000!important}#readingProgress,.top-badge-bar,.site-header,.sidebar,.sidebar-overlay,.course-sidebar,.course-sidebar-toggle,.t-btn,.course-tools,.chapter-nav,.ml-footer,#goTopBtn,.skip-link{display:none!important}.wrap{width:100%;margin:0;padding:0}.lay{display:block}.course-content{border:0!important;box-shadow:none!important;background:#fff!important}.course-content,.course-content *{color:#000!important}.engc-card,.engc-panel,.hero{break-inside:avoid;background:#fff!important;box-shadow:none!important}}:root{--edu-teal:#2A9D8F;--edu-coral:#F4A261;--edu-cream:#FFF3D6;--edu-ink:#20313A;--edu-muted:#58666E;--edu-line:#AAB9BA;--edu-soft:linear-gradient(120deg,rgba(255,243,214,.98) 0%,rgba(42,157,143,.22) 50%,rgba(244,162,97,.78) 100%);--edu-soft-reverse:linear-gradient(120deg,rgba(244,162,97,.82) 0%,rgba(42,157,143,.24) 50%,rgba(255,243,214,.98) 100%);--edu-strong:linear-gradient(120deg,var(--edu-cream) 0%,var(--edu-teal) 50%,var(--edu-coral) 100%);}html,body{color:var(--edu-ink)!important;background:linear-gradient(135deg,var(--edu-cream) 0%,rgba(42,157,143,.24) 48%,rgba(244,162,97,.66) 100%)!important;background-attachment:fixed!important}.top-badge-bar,.translator-bar,.card,.card>.hd,.course-content,.course-sidebar,.side,.course-tools,.topic-jump-nav,.engc-card,.engc-panel,.ml-footer{background:var(--edu-soft)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}.site-header,.main-nav{background:rgba(255,243,214,.88)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important;box-shadow:0 10px 28px rgba(32,49,58,.07)!important}.hero{background:var(--edu-soft-reverse)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}.hero .engc-title,.hero .sub,.top-badge-bar,.top-badge-bar p,.top-badge-bar .top-pill,.translator-label,.logo-tagline,.ml-copy,.ml-policy-note,.ml-legal-note{color:var(--edu-ink)!important}.nav-links a,.chapter-group .link,.tool-btn,.course-sidebar-tools button,.course-sidebar-toggle,.course-sidebar-close,.menu-toggle,.close-btn,.t-btn,#goTopBtn,.chapter-nav a,.topic-jump-links a,.copy-code,.ml-footer-social a{background:var(--edu-soft)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}.nav-links a:hover,.nav-links a.active,.chapter-group .link:hover,.chapter-group.active-chapter .link,.topic-jump-links a:hover,.topic-jump-links a:focus-visible,.tool-btn:hover,.course-sidebar-tools button:hover,.chapter-nav a:hover,.ml-footer-social a:hover{background:var(--edu-strong)!important;color:#17343A!important}.pill,.topic-example-heading{background:var(--edu-soft-reverse)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}.course-sidebar-tools input,#google_translate_element select.goog-te-combo{background:#fff!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}#readingProgress{background:linear-gradient(90deg,var(--edu-cream),var(--edu-teal),var(--edu-coral))!important}.translator-bar{position:relative;z-index:1100;width:min(1480px,96%);margin:10px auto 15px;padding:11px 15px;display:flex;align-items:center;justify-content:center;gap:10px;flex-wrap:wrap;border-radius:14px;box-shadow:0 10px 24px rgba(32,49,58,.08)!important}.translator-label{font-weight:850;font-size:.94rem}#google_translate_element{min-width:220px;max-width:100%}#google_translate_element .goog-te-gadget{font-size:.82rem!important;color:var(--edu-ink)!important;font-weight:650!important}#google_translate_element .goog-te-gadget-simple{background:var(--edu-soft-reverse)!important;border:1px solid var(--edu-line)!important;border-radius:10px!important;padding:7px 10px!important}#google_translate_element select.goog-te-combo{min-width:190px!important;max-width:100%!important;padding:8px 10px!important;border-radius:9px!important;font-weight:700!important;cursor:pointer!important}.ml-footer-social a{width:44px;height:44px;padding:0;display:inline-flex;align-items:center;justify-content:center;border-radius:50%;text-decoration:none}.social-icon{width:22px;height:22px;display:block;fill:none;stroke:currentColor;stroke-width:1.9;stroke-linecap:round;stroke-linejoin:round}.social-icon.fill-icon{fill:currentColor;stroke:none}a[href],button,label[for],select,[role="button"],.tool-btn,.chapter-group .link,.topic-jump-links a,.ml-footer-social a,.copy-code{transition:transform .14s ease,box-shadow .14s ease,filter .14s ease,opacity .14s ease,background .14s ease!important}@media(hover:hover){a[href]:hover,button:hover,label[for]:hover,select:hover,[role="button"]:hover,.tool-btn:hover,.chapter-group .link:hover,.topic-jump-links a:hover,.ml-footer-social a:hover,.copy-code:hover{filter:saturate(1.08) brightness(1.02);box-shadow:0 7px 18px rgba(42,157,143,.18);transform:translateY(-2px)}}a[href]:active,button:active,label[for]:active,select:active,[role="button"]:active,.is-clicked{transform:translateY(1px) scale(.97)!important;filter:brightness(.96) saturate(1.12)!important;box-shadow:0 3px 9px rgba(32,49,58,.12)!important}a[href]:focus-visible,button:focus-visible,label[for]:focus-visible,select:focus-visible,[role="button"]:focus-visible{outline:3px solid rgba(42,157,143,.44)!important;outline-offset:3px!important}html.etg-rtl,html.etg-rtl body{direction:rtl!important;text-align:right!important}html.etg-rtl .site-header,html.etg-rtl .translator-bar,html.etg-rtl .lay,html.etg-rtl .course-content,html.etg-rtl .engc-card,html.etg-rtl .engc-panel,html.etg-rtl .tutorial-section,html.etg-rtl .topic-jump-nav,html.etg-rtl .breadcrumbs,html.etg-rtl .course-tools,html.etg-rtl .course-sidebar,html.etg-rtl .chapter-nav,html.etg-rtl footer{direction:rtl!important;text-align:right!important}html.etg-rtl ol,html.etg-rtl ul{padding-right:1.45rem!important;padding-left:0!important}html.etg-rtl input,html.etg-rtl select,html.etg-rtl textarea{direction:rtl!important;text-align:right!important}html.etg-rtl pre,html.etg-rtl code{direction:ltr!important;text-align:left!important}body.dark-view{--surface:#243036!important;--surface-strong:#243036!important;--text:#F6FAFA!important;--muted:#D7E2E0!important;--line:#637576!important;background:#1B262B!important;color:#F6FAFA!important}body.dark-view .card,body.dark-view .course-content,body.dark-view .course-sidebar,body.dark-view .side,body.dark-view .engc-card,body.dark-view .engc-panel{background:#243036!important;color:#F6FAFA!important;border-color:#637576!important}body.dark-view .top-badge-bar,body.dark-view .hero,body.dark-view .course-tools,body.dark-view .topic-jump-nav,body.dark-view .translator-bar,body.dark-view .ml-footer,body.dark-view .card>.hd,body.dark-view .chapter-group.active-chapter .link,body.dark-view .chapter-group .link:hover{background:var(--edu-strong)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}body.dark-view .top-badge-bar p,body.dark-view .top-badge-bar .top-pill,body.dark-view .hero .engc-title,body.dark-view .hero .sub,body.dark-view .translator-label,body.dark-view .ml-copy,body.dark-view .ml-policy-note,body.dark-view .ml-legal-note{color:var(--edu-ink)!important}body.dark-view .tool-btn,body.dark-view .course-sidebar-tools button,body.dark-view .t-btn,body.dark-view #goTopBtn,body.dark-view .chapter-nav a,body.dark-view .topic-jump-links a,body.dark-view .copy-code,body.dark-view .ml-footer-social a{background:var(--edu-soft-reverse)!important;color:var(--edu-ink)!important;border-color:var(--edu-line)!important}body.dark-view .course-sidebar-tools input{background:#303E43!important;color:#F6FAFA!important;border-color:#637576!important}@media(max-width:700px){.translator-bar{width:96%;flex-direction:column;align-items:stretch;text-align:center}.translator-label{display:block}#google_translate_element{width:100%}#google_translate_element select.goog-te-combo{width:100%!important;min-width:0!important}}@media(prefers-reduced-motion:reduce){a[href],button,label[for],select,[role="button"]{transition:none!important;transform:none!important}}@media print{.translator-bar{display:none!important}}.ml-legal-note,.ml-policy-note{margin:9px auto 0;max-width:920px;font-size:.78rem;line-height:1.5}:root{--g6-indigo:#8B80F9;--g6-aqua:#74DDE8;--g6-apricot:#FFD6A5;--g6-ink:#1F2A44;--g6-muted:#56637A;--g6-border:#B9C7D8;--g6-grad:linear-gradient(120deg,var(--g6-indigo) 0%,var(--g6-aqua) 50%,var(--g6-apricot) 100%);--g6-rev:linear-gradient(120deg,var(--g6-apricot) 0%,var(--g6-aqua) 50%,var(--g6-indigo) 100%);}html,body{background:linear-gradient(135deg,#F2F0FF 0%,#E5FBFD 50%,#FFF2E2 100%)!important;color:var(--g6-ink)!important;background-attachment:fixed!important}.top-badge-bar,.translator-bar,.card>.hd,.course-tools,.topic-jump-nav,.ml-footer{background:var(--g6-grad)!important;color:var(--g6-ink)!important;border-color:var(--g6-border)!important}.site-header,.main-nav{background:rgba(255,255,255,.78)!important;color:var(--g6-ink)!important;border-color:transparent!important}.card,.course-content,.engc-card,.engc-panel,.example-panel,.course-sidebar,.side{background:linear-gradient(145deg,rgba(255,255,255,.97),rgba(241,252,255,.95),rgba(255,246,232,.96))!important;border-color:var(--g6-border)!important}.hero,.topic-example-heading,.pill{background:var(--g6-rev)!important;color:var(--g6-ink)!important;border-color:var(--g6-border)!important}.nav-links a,.chapter-group .link,.tool-btn,.chapter-nav a,.topic-jump-links a,.copy-code,.course-sidebar-tools button,.course-sidebar-toggle,.course-sidebar-close,.menu-toggle,.close-btn,.t-btn,#goTopBtn,.ml-footer-social a{background:linear-gradient(120deg,#F0EEFF 0%,#E5FBFD 52%,#FFF2E2 100%)!important;color:var(--g6-ink)!important;border-color:var(--g6-border)!important}.nav-links a:hover,.nav-links a.active,.chapter-group .link:hover,.chapter-group.active-chapter .link,.tool-btn:hover,.chapter-nav a:hover,.topic-jump-links a:hover,.copy-code:hover,.ml-footer-social a:hover{background:var(--g6-grad)!important;color:#16213A!important;transform:translateY(-2px);box-shadow:0 8px 20px rgba(91,93,170,.18)!important}button:active,a:active,.tool-btn:active,.topic-jump-links a:active,.chapter-group .link:active,.ml-footer-social a:active{transform:translateY(1px) scale(.98)!important}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid rgba(139,128,249,.42)!important;outline-offset:3px!important}#readingProgress{background:linear-gradient(90deg,var(--g6-indigo),var(--g6-aqua),var(--g6-apricot))!important}.engc-panel.example-panel,.math-example,.math-explanation,.math-answer{border-left-color:var(--g6-indigo)!important}html.etg-rtl .engc-panel,html.etg-rtl .math-example,html.etg-rtl .math-explanation,html.etg-rtl .math-answer{border-left-color:var(--g6-border)!important;border-right-color:var(--g6-indigo)!important}.social-icon{width:21px;height:21px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}.social-icon.fill-icon,.fill-icon{fill:currentColor;stroke:none}body.dark-view{background:#172033!important;color:#F3F7FF!important}body.dark-view .card,body.dark-view .course-content,body.dark-view .engc-card,body.dark-view .engc-panel,body.dark-view .course-sidebar,body.dark-view .side{background:#222C40!important;color:#F3F7FF!important;border-color:#52617A!important}body.dark-view .top-badge-bar,body.dark-view .translator-bar,body.dark-view .hero,body.dark-view .course-tools,body.dark-view .topic-jump-nav,body.dark-view .ml-footer,body.dark-view .card>.hd{background:linear-gradient(120deg,#6259B5,#378F99,#A77949)!important;color:#FFFFFF!important;border-color:#66728B!important}body.dark-view .hero *,body.dark-view .top-badge-bar *,body.dark-view .translator-bar *,body.dark-view .ml-footer *{color:#FFFFFF!important}body.dark-view .nav-links a:hover,body.dark-view .nav-links a.active,body.dark-view .chapter-group .link:hover,body.dark-view .chapter-group.active-chapter .link,body.dark-view .tool-btn,body.dark-view .chapter-nav a,body.dark-view .topic-jump-links a,body.dark-view .copy-code,body.dark-view .ml-footer-social a{background:linear-gradient(120deg,#6259B5,#378F99,#A77949)!important;color:#FFFFFF!important;border-color:#71809B!important}@media(max-width:1020px){.sidebar,.sidebar a{background:linear-gradient(160deg,#F0EEFF,#E5FBFD,#FFF2E2)!important;color:var(--g6-ink)!important}}:root{--g4-blue:#2F80ED;--g4-mint:#A7F3D0;--g4-peach:#FFD6A5;--g4-ink:#17324D;--g4-line:#AABFD3;--g4-grad:linear-gradient(120deg,var(--g4-blue) 0%,var(--g4-mint) 52%,var(--g4-peach) 100%);--g4-soft:linear-gradient(120deg,#EAF4FF 0%,#E9FFF6 52%,#FFF2DF 100%);}html,body{background:linear-gradient(135deg,#EAF4FF 0%,#E9FFF6 52%,#FFF2DF 100%)!important;color:var(--g4-ink)!important}.top-badge-bar,.translator-bar,.hero,.card>.hd,.course-tools,.topic-jump-nav,.ml-footer{background:var(--g4-grad)!important;color:var(--g4-ink)!important;border-color:var(--g4-line)!important}.site-header,.card,.course-sidebar,.course-content,.engc-card,.engc-panel,.example-panel{background:var(--g4-soft)!important;color:var(--g4-ink)!important;border-color:var(--g4-line)!important}.nav-links a,.chapter-group .link,.tool-btn,.course-sidebar-tools button,.chapter-nav a,.topic-jump-links a,.copy-code,.ml-footer-social a,.pill,.t-btn,#goTopBtn,.menu-toggle,.close-btn{background:var(--g4-soft)!important;color:var(--g4-ink)!important;border-color:var(--g4-line)!important}.nav-links a:hover,.chapter-group .link:hover,.chapter-group.active-chapter .link,.tool-btn:hover,.chapter-nav a:hover,.topic-jump-links a:hover,.ml-footer-social a:hover,.copy-code:hover{background:var(--g4-grad)!important;color:#12314A!important;transform:translateY(-1px);box-shadow:0 8px 20px rgba(47,128,237,.16)!important}a,button,.tool-btn,.chapter-group .link,.topic-jump-links a,.ml-footer-social a{transition:transform .14s ease,box-shadow .14s ease,filter .14s ease!important}a:active,button:active{transform:translateY(1px) scale(.98)!important}.engc-sec-title,.topic-example-heading{background:var(--g4-grad)!important;color:#17324D!important}.math-explanation{background:linear-gradient(120deg,#E9FFF6,#FFF7EA)!important}.math-answer{background:linear-gradient(120deg,#EAF4FF,#E9FFF6)!important}#readingProgress{background:linear-gradient(90deg,var(--g4-blue),var(--g4-mint),var(--g4-peach))!important}body.dark-view{background:#17202A!important;color:#F7FAFC!important}body.dark-view .card,body.dark-view .course-content,body.dark-view .course-sidebar,body.dark-view .engc-card,body.dark-view .engc-panel{background:#22303D!important;color:#F7FAFC!important;border-color:#52687A!important}body.dark-view .top-badge-bar,body.dark-view .translator-bar,body.dark-view .hero,body.dark-view .card>.hd,body.dark-view .course-tools,body.dark-view .topic-jump-nav,body.dark-view .ml-footer{background:linear-gradient(120deg,#245D9D,#397F6B,#9C744A)!important;color:#FFF!important}body.dark-view .engc-sec-title,body.dark-view .topic-example-heading{background:linear-gradient(120deg,#245D9D,#397F6B,#9C744A)!important;color:#FFF!important}@media(max-width:1020px){.sidebar,.sidebar a{background:var(--g4-soft)!important;color:var(--g4-ink)!important}}