:root,
html[data-theme="light"]{
  --paper:#f7f9f8;
  --paper-2:#edf3f1;
  --card:#ffffff;
  --ink:#17211e;
  --ink-soft:#41514c;
  --ink-faint:#6e7c77;
  --line:rgba(23,33,30,.16);
  --line-soft:rgba(23,33,30,.09);
  --accent:#0b7768;
  --accent-2:#075e53;
  --accent-soft:rgba(11,119,104,.09);
  --gold:#b5842a;
  --gold-soft:#fff4d6;
  --success:#0b7768;
  --danger:#a9443e;
  --shadow:0 2px 10px rgba(28,45,39,.07);
  --shadow-lg:0 14px 36px rgba(28,45,39,.12);
  --radius:14px;
  --sidebar-w:304px;
  --fs-base:17.25px;
  --rhythm:1.78;
}
html[data-theme="dark"]{
  --paper:#111315;
  --paper-2:#20252a;
  --card:#181c1f;
  --ink:#f3f6f5;
  --ink-soft:#c3cdca;
  --ink-faint:#8d9995;
  --line:rgba(225,235,232,.18);
  --line-soft:rgba(225,235,232,.10);
  --accent:#5cc7b2;
  --accent-2:#7bd8c5;
  --accent-soft:rgba(92,199,178,.12);
  --gold:#e0a93f;
  --gold-soft:#2d2511;
  --success:#5cc7b2;
  --danger:#e88b84;
  --shadow:0 2px 12px rgba(0,0,0,.25);
  --shadow-lg:0 18px 48px rgba(0,0,0,.36);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:'Hind','Noto Sans Devanagari',system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
  font-size:var(--fs-base);
  line-height:var(--rhythm);
  text-rendering:optimizeLegibility;
  -webkit-font-smoothing:antialiased;
}
a{color:var(--accent-2)}
h1,h2,h3,h4,.display{font-family:'Poppins','Tiro Devanagari Hindi','Hind',sans-serif;color:var(--ink);letter-spacing:-.2px;line-height:1.25}
.mono{font-family:'JetBrains Mono',ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
.progress-shell{
  position:sticky;top:0;z-index:50;
  min-height:46px;
  padding:6px 14px;
  border-bottom:1px solid var(--line);
  background:color-mix(in srgb,var(--card) 94%,transparent);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  display:flex;align-items:center;gap:9px;
}
.app .progress-shell{grid-column:1/-1}
.topbar-title{flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;font-size:14px;font-weight:800}
.section-indicator{flex:0 1 460px;min-width:0;display:flex;align-items:center;gap:7px;padding:5px 11px;border:1px solid var(--line-soft);border-radius:999px;background:color-mix(in srgb,var(--card) 86%,transparent);color:var(--ink-soft);font-size:12px;font-weight:700;line-height:1.35;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.section-indicator i{color:var(--accent-2);flex:0 0 auto}.section-indicator span{overflow:hidden;text-overflow:ellipsis}
.progress-label{min-width:116px;text-align:right;font-size:12px;font-weight:800;color:var(--ink-soft)}
.topbtn{width:34px;height:34px;border:1px solid var(--line);border-radius:10px;background:var(--card);color:var(--ink);cursor:pointer;display:grid;place-items:center;text-decoration:none;font-weight:900;transition:transform .15s ease,background .2s ease,border-color .2s ease}
.topbtn:hover,.topbtn.active{transform:translateY(-1px);border-color:var(--accent);background:var(--accent-soft)}
.app{display:grid;grid-template-columns:var(--sidebar-w) minmax(0,1fr);min-height:100vh}
.sidebar{grid-row:2;position:sticky;top:46px;height:calc(100vh - 46px);overflow:auto;padding:18px 14px 28px;border-right:1px solid var(--line);background:var(--paper-2)}
.sidebar::-webkit-scrollbar{width:8px}.sidebar::-webkit-scrollbar-thumb{background:var(--line);border-radius:8px}
.brand-card{padding:16px;border:1px solid var(--line);border-radius:var(--radius);background:var(--card);box-shadow:var(--shadow);margin-bottom:14px}.brand-card strong{display:block;font-size:18px;line-height:1.25}.brand-card span{display:block;margin-top:5px;font-size:12px;color:var(--ink-faint);line-height:1.55}
.side-link{display:flex;align-items:center;justify-content:center;gap:8px;margin:0 2px 12px;padding:8px 10px;border:1px solid var(--line);border-radius:10px;background:var(--card);color:var(--accent-2);text-decoration:none;font-size:13px;font-weight:800}.side-link:hover{border-color:var(--accent);color:var(--ink)}
.toc-toolbar{display:grid;grid-template-columns:1fr 1fr 1fr;gap:7px;margin:10px 0 14px}.toc-tab{border:1px solid var(--line);background:var(--card);border-radius:10px;padding:7px 5px;color:var(--ink-soft);font-size:12px;font-weight:800;cursor:pointer}.toc-tab.active{background:var(--accent);border-color:var(--accent);color:#fff}.badge{font-family:'JetBrains Mono',monospace;font-size:10px;margin-left:3px}.toc-label{margin:14px 8px 8px;color:var(--ink-faint);font-size:11px;font-weight:800;text-transform:uppercase;letter-spacing:1px}.toc-list{display:flex;flex-direction:column;gap:7px}.toc-link{display:flex;gap:8px;align-items:flex-start;padding:9px 10px;border:1px solid transparent;border-radius:10px;color:var(--ink-soft);text-decoration:none;font-size:13px;font-weight:700;line-height:1.35}.toc-link:hover,.toc-link.active{background:var(--card);border-color:var(--line);color:var(--ink)}.toc-link.done::after{content:'✓';margin-left:auto;color:var(--success);font-weight:900}.toc-link.bookmarked{border-color:color-mix(in srgb,var(--accent) 42%,var(--line))}
#sidebar-scrim{display:none}
main{grid-row:2;min-width:0}.reader{width:min(1040px,100%);margin:0 auto;padding:38px clamp(16px,4vw,46px) 76px}.page-breadcrumb{display:flex;gap:8px;align-items:center;flex-wrap:wrap;color:var(--ink-faint);font-size:12px;font-weight:700;margin:0 0 18px}.page-breadcrumb a{text-decoration:none;color:var(--accent-2)}.page-breadcrumb a:hover{text-decoration:underline}.page-breadcrumb i{font-size:9px;color:var(--line)}
.hero,.category-hero{padding:30px 0 32px;border-bottom:2px solid var(--line);margin-bottom:30px}.eyebrow{display:block;color:var(--accent-2);font-size:12px;font-weight:900;letter-spacing:2px;text-transform:uppercase}.hero h1,.category-hero h1{margin:9px 0 12px;font-size:clamp(31px,5vw,52px);border-bottom:3px solid var(--accent);padding-bottom:14px}.hero p,.category-hero p{max-width:850px;margin:0;color:var(--ink-soft);font-size:18px;text-align:justify}.hero-meta,.category-stats{display:flex;flex-wrap:wrap;gap:10px;margin-top:20px}.hero-meta span,.category-stats span,.pill{display:inline-flex;align-items:center;gap:7px;padding:7px 11px;border:1px solid var(--line);border-radius:999px;background:var(--card);color:var(--ink-soft);font-size:12px;font-weight:800}.source-box,.exam-box,.note-box{margin:16px 0;padding:14px 16px;border:1px solid var(--line);border-radius:var(--radius);background:var(--card);box-shadow:var(--shadow)}.source-box{border-left:4px solid var(--accent)}.exam-box{background:var(--gold-soft);border-left:4px solid var(--gold)}.note-box{background:var(--accent-soft);border-left:4px solid var(--accent)}.note-box b,.exam-box b,.source-box b{display:block;margin-bottom:5px;color:var(--accent-2)}
.card{position:relative;margin:22px 0;padding:24px clamp(16px,3vw,28px);background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);scroll-margin-top:68px}.card h2{margin:0 0 18px;font-size:clamp(23px,3vw,30px);display:flex;gap:10px;align-items:flex-start}.idx{flex:0 0 auto;display:inline-grid;place-items:center;width:38px;height:38px;border-radius:11px;background:var(--accent);color:#fff;font-size:14px;font-family:'JetBrains Mono',monospace}.actions{margin-left:auto;display:flex;gap:8px}.h2-btn{border:1px solid var(--line);border-radius:9px;background:var(--paper);color:var(--ink);width:34px;height:34px;cursor:pointer}.h2-btn.active{background:var(--accent);border-color:var(--accent);color:#fff}.card h3{margin:20px 0 8px;font-size:21px}ul{padding-left:22px;margin:8px 0}li{margin:7px 0}.sub-list{margin-top:5px;color:var(--ink-soft)}strong{color:var(--ink)}
.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:16px}.fact-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin:16px 0}.fact{padding:14px;border:1px solid var(--line);border-radius:12px;background:var(--paper)}.fact small{display:block;color:var(--ink-faint);font-weight:800}.fact strong{display:block;font-size:17px}.timeline{position:relative;margin:18px 0}.timeline::before{content:'';position:absolute;left:18px;top:8px;bottom:8px;width:2px;background:var(--line)}.time-item{position:relative;padding:0 0 16px 52px}.time-item::before{content:'';position:absolute;left:10px;top:6px;width:18px;height:18px;border-radius:999px;background:var(--accent);box-shadow:0 0 0 4px var(--accent-soft)}.time-item b{display:block;color:var(--accent-2)}
.table-wrap{overflow:auto;border:1px solid var(--line);border-radius:13px;margin:14px 0;background:var(--card)}table{width:100%;border-collapse:collapse;min-width:720px}th,td{border-bottom:1px solid var(--line-soft);border-right:1px solid var(--line-soft);padding:12px 14px;text-align:left;vertical-align:top}th{background:var(--paper-2);font-weight:900;color:var(--ink)}td:first-child{font-weight:900;color:var(--accent-2)}.complete-row{display:flex;gap:12px;align-items:center;justify-content:space-between;border-top:1px solid var(--line-soft);padding-top:16px;margin-top:18px}.complete-btn{border:1px solid var(--line);background:var(--paper);color:var(--ink);border-radius:999px;padding:8px 13px;font-weight:800;cursor:pointer}.complete-btn.done{background:var(--accent);border-color:var(--accent);color:#fff}.section-meta{color:var(--ink-faint);font-size:12px;font-weight:800}.quick-revision{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.rev-card{padding:13px;border:1px solid var(--line);border-radius:12px;background:var(--paper)}.rev-card b{color:var(--accent-2)}
.quiz-launch{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:18px;border:1px solid var(--line);border-radius:14px;background:linear-gradient(135deg,var(--accent-soft),transparent);margin-top:14px}.primary-btn{border:0;border-radius:999px;padding:10px 16px;background:var(--accent);color:#fff;font-weight:900;cursor:pointer}.outline-btn{border:1px solid var(--line);border-radius:999px;padding:9px 14px;background:var(--card);color:var(--ink);font-weight:800;cursor:pointer}
.category-page{min-height:100vh}.category-main{padding:46px 24px 80px}.category-reader{width:min(1080px,100%);margin:0 auto}.category-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:20px 0 28px}.category-card{display:grid;grid-template-columns:52px 1fr;gap:16px;min-height:150px;padding:18px;border:1px solid var(--line);border-radius:var(--radius);background:var(--card);box-shadow:var(--shadow);transition:transform .15s ease,border-color .2s ease}.category-card:hover{transform:translateY(-2px);border-color:var(--accent)}.category-card.disabled{opacity:.68}.card-icon{width:52px;height:52px;border-radius:15px;background:var(--accent-soft);color:var(--accent-2);display:grid;place-items:center;font-size:23px}.card-kicker{display:block;color:var(--ink-faint);font-family:'JetBrains Mono',monospace;font-size:11px;font-weight:800;line-height:1.45}.category-card h2{margin:5px 0 7px;font-size:22px}.category-card h2 a{color:var(--ink);text-decoration:none}.category-card p{margin:0;color:var(--ink-soft);font-size:14px;line-height:1.65}.card-action{display:inline-flex;align-items:center;gap:8px;margin-top:12px;color:var(--accent-2);font-size:13px;font-weight:900;text-decoration:none}.category-note{display:flex;gap:14px;margin-top:20px;padding:16px;border:1px solid var(--line);border-radius:var(--radius);background:var(--gold-soft)}.category-note i{color:var(--gold);margin-top:4px}.category-note strong{display:block}.category-note p{margin:4px 0 0;color:var(--ink-soft)}
.quiz-overlay{position:fixed;inset:0;z-index:100;display:none;background:rgba(0,0,0,.48);padding:18px}.quiz-overlay.open{display:grid;place-items:center}.quiz-modal{width:min(820px,100%);max-height:min(760px,92vh);overflow:hidden;display:grid;grid-template-rows:auto 1fr auto;background:var(--card);border-radius:18px;border:1px solid var(--line);box-shadow:var(--shadow-lg)}.quiz-head{padding:16px 18px;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;gap:12px;align-items:center}.quiz-head h2{margin:0;font-size:23px}.quiz-bar{height:6px;background:var(--line-soft)}.quiz-fill{height:100%;width:0;background:var(--accent);transition:width .2s ease}.quiz-body{padding:20px;overflow:auto}.q-title{font-size:20px;font-weight:900;line-height:1.45;margin-bottom:16px}.options{display:grid;gap:10px}.opt{text-align:left;border:1px solid var(--line);border-radius:12px;background:var(--paper);color:var(--ink);padding:12px 14px;font-weight:800;cursor:pointer}.opt:hover{border-color:var(--accent)}.opt.selected{border-color:var(--accent);background:var(--accent-soft)}.opt.correct{border-color:var(--success);background:color-mix(in srgb,var(--success) 16%,var(--card))}.opt.wrong{border-color:var(--danger);background:color-mix(in srgb,var(--danger) 13%,var(--card))}.explain{margin-top:14px;padding:14px;border-radius:12px;border:1px solid var(--line);background:var(--gold-soft)}.quiz-foot{display:flex;justify-content:space-between;gap:10px;align-items:center;padding:14px 18px;border-top:1px solid var(--line)}.result-box{text-align:center;padding:24px}.score{margin:auto;width:120px;height:120px;border-radius:999px;display:grid;place-items:center;background:var(--accent);color:#fff;font-size:30px;font-weight:900;font-family:'JetBrains Mono',monospace}
.mobile-only{display:none}
@media(max-width:880px){.app{display:block}.sidebar{position:fixed;left:0;top:46px;bottom:0;height:auto;width:min(320px,86vw);z-index:70;transform:translateX(-104%);box-shadow:var(--shadow-lg)}.sidebar.open{transform:translateX(0)}#sidebar-scrim.open{display:block;position:fixed;inset:46px 0 0 0;z-index:60;background:rgba(0,0,0,.35)}.mobile-only{display:grid}.reader{padding:28px 14px 70px}.section-indicator{flex:1}.topbar-title{display:none}.progress-label{min-width:88px;font-size:10px}.grid-2,.fact-grid,.quick-revision,.category-grid{grid-template-columns:1fr}.complete-row,.quiz-launch{align-items:flex-start;flex-direction:column}.category-main{padding:30px 14px 70px}.category-card{grid-template-columns:44px 1fr}.card-icon{width:44px;height:44px;font-size:19px}}
@media(max-width:520px){body{font-size:16.25px}.progress-shell{padding:5px 7px;gap:5px}.topbtn{width:31px;height:31px}.hero h1,.category-hero h1{font-size:30px}.hero p,.category-hero p{text-align:left;font-size:16.5px}.card{padding:18px 14px}.card h2{font-size:22px}.idx{width:34px;height:34px}.toc-toolbar{grid-template-columns:1fr}.quiz-head{align-items:flex-start}.quiz-modal{max-height:94vh}}


/* ---------- SEO + student reading improvements ---------- */
.skip-link{position:absolute;left:12px;top:-48px;z-index:999;padding:9px 12px;border-radius:10px;background:var(--accent);color:#fff;text-decoration:none;font-weight:900;transition:top .18s ease}.skip-link:focus{top:10px}
.help-text{margin:6px 0 18px;color:var(--ink-faint);font-size:13px;font-weight:700}.student-flow{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:13px;margin:0 0 24px}.student-flow article,.learning-card,.roadmap-box,.related-links{border:1px solid var(--line);border-radius:var(--radius);background:var(--card);box-shadow:var(--shadow)}.student-flow article{padding:15px}.student-flow b,.learning-card b,.roadmap-box h2,.related-links h2{display:block;color:var(--accent-2);font-size:16px;margin:0 0 6px}.student-flow span{display:block;color:var(--ink-soft);font-size:14px;line-height:1.6}.learning-card{margin:16px 0;padding:16px;border-left:4px solid var(--accent)}.learning-card ul{margin-bottom:0}.summary-card{background:linear-gradient(135deg,var(--accent-soft),var(--card) 55%)}.snapshot-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.snapshot-grid div{padding:13px;border:1px solid var(--line-soft);border-radius:12px;background:color-mix(in srgb,var(--card) 88%,transparent)}.snapshot-grid b{display:block;color:var(--accent-2);font-size:12px;text-transform:uppercase;letter-spacing:.6px}.snapshot-grid span{display:block;color:var(--ink-soft);font-weight:700;line-height:1.55}.roadmap-box{margin:22px 0;padding:18px}.roadmap-box h2,.related-links h2{font-size:22px}.roadmap-list{display:flex;flex-wrap:wrap;gap:9px}.roadmap-list span,.related-links a,.related-links span{display:inline-flex;align-items:center;padding:8px 11px;border:1px solid var(--line);border-radius:999px;background:var(--paper);color:var(--ink-soft);font-size:13px;font-weight:800;text-decoration:none}.related-links{margin:24px 0 0;padding:18px}.related-links a{color:var(--accent-2)}#categorySearch{width:100%;font:inherit;margin-top:0}.category-card.disabled{opacity:.82}.category-card.disabled h2{color:var(--ink-soft)}.card:target{outline:3px solid color-mix(in srgb,var(--accent) 36%,transparent);outline-offset:3px}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid color-mix(in srgb,var(--accent) 60%,transparent);outline-offset:2px}
@media(max-width:900px){.student-flow,.snapshot-grid{grid-template-columns:1fr 1fr}.hero p,.category-hero p{text-align:left}}
@media(max-width:620px){.student-flow,.snapshot-grid{grid-template-columns:1fr}.roadmap-list span,.related-links a,.related-links span{width:100%;justify-content:center}.hero-meta span,.category-stats span{font-size:11px}.card{scroll-margin-top:84px}}
@media print{.progress-shell,.sidebar,#sidebar-scrim,.complete-row,.quiz-overlay,.related-links,.toc-toolbar,.skip-link{display:none!important}.app{display:block}.reader{width:100%;padding:0}.card,.hero{box-shadow:none;border-color:#bbb;break-inside:avoid}body{background:#fff;color:#000;font-size:12pt}.card h2{font-size:18pt}a{color:#000;text-decoration:none}}


/* PDF-style notes cleanup: content stays plain, readable and close to the source notes. */
.hero p{max-width:900px;}
.card > p{margin:0 0 14px;color:var(--ink-soft);font-size:1.03rem;line-height:1.85;}
.card h3{margin:22px 0 9px;font-size:1.12rem;line-height:1.45;color:var(--ink);}
.card ul{margin:8px 0 14px 1.15rem;padding:0;}
.card li{margin:7px 0;line-height:1.85;}
.plain-note{margin-top:10px;color:var(--ink-soft);font-size:1rem;}
.table-wrap table{border-collapse:collapse;min-width:720px;}
.table-wrap th,.table-wrap td{border:1px solid var(--line);vertical-align:top;line-height:1.65;}
.table-wrap th{font-weight:800;background:var(--paper-2);}
@media(max-width:760px){.card{padding:18px 15px}.card h3{font-size:1.06rem}.table-wrap table{min-width:680px}.hero-meta{gap:8px}.hero-meta span{font-size:12px}}
@media print{.source-box,.learning-card,.summary-card,.exam-box,.quick-revision,.quiz-launch,.related-links{display:none!important}.app{display:block}.sidebar,.progress-shell{display:none}.reader{width:100%;max-width:none}.card{break-inside:avoid;border:0;box-shadow:none}.table-wrap{overflow:visible}.table-wrap table{min-width:0;width:100%}}

/* quiz type badge */
.q-type{display:inline-flex;align-items:center;width:max-content;margin:0 0 9px;padding:4px 9px;border:1px solid var(--line);border-radius:999px;background:var(--accent-soft);color:var(--accent-2);font-family:'JetBrains Mono',monospace;font-size:11px;font-weight:900}.q-title{display:grid;gap:2px}.opt b{font-family:'JetBrains Mono',monospace;margin-right:4px}

/* ---------- Improved quiz experience ---------- */
body.quiz-open{overflow:hidden;touch-action:none}
.sr-only{position:absolute!important;width:1px!important;height:1px!important;padding:0!important;margin:-1px!important;overflow:hidden!important;clip:rect(0,0,0,0)!important;white-space:nowrap!important;border:0!important}
.quiz-overlay{position:fixed;inset:0;z-index:1000;display:none;padding:clamp(10px,2vw,24px);background:rgba(7,14,18,.72);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px)}
.quiz-overlay.open{display:grid;place-items:center;animation:quizFadeIn .18s ease-out}
.quiz-modal{width:min(860px,100%);height:min(820px,96dvh);max-height:96dvh;overflow:hidden;display:grid;grid-template-rows:auto auto 6px minmax(0,1fr) auto;background:var(--card);border:1px solid color-mix(in srgb,var(--accent) 26%,var(--line));border-radius:24px;box-shadow:0 28px 80px rgba(0,0,0,.36);outline:none;animation:quizRise .22s ease-out}
.quiz-head{padding:20px 22px 15px;border:0;display:flex;align-items:flex-start;justify-content:space-between;gap:18px;background:linear-gradient(135deg,color-mix(in srgb,var(--accent-soft) 70%,var(--card)),var(--card) 62%)}
.quiz-heading-copy{min-width:0}.quiz-eyebrow{display:inline-flex;align-items:center;gap:7px;margin-bottom:7px;color:var(--accent-2);font-family:'JetBrains Mono',monospace;font-size:10px;font-weight:800;letter-spacing:.08em;text-transform:uppercase}.quiz-head h2{margin:0;color:var(--ink);font-size:clamp(22px,3vw,30px);line-height:1.2}.quiz-head p{margin:6px 0 0;color:var(--ink-soft);font-size:13px;line-height:1.5}
.quiz-close{flex:0 0 auto;width:40px;height:40px;border:1px solid var(--line);border-radius:12px;display:grid;place-items:center;background:var(--card);color:var(--ink-soft);font-size:17px;cursor:pointer;transition:transform .16s ease,border-color .16s ease,color .16s ease,background .16s ease}.quiz-close:hover{transform:translateY(-1px);border-color:var(--danger);color:var(--danger);background:color-mix(in srgb,var(--danger) 7%,var(--card))}
.quiz-status{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:9px 22px;border-top:1px solid var(--line-soft);background:var(--card);color:var(--ink-soft);font-family:'JetBrains Mono',monospace;font-size:11px;font-weight:700}.quiz-counter{color:var(--ink)}.quiz-answered{white-space:nowrap}
.quiz-bar{height:6px;background:var(--line-soft);overflow:hidden}.quiz-fill{height:100%;width:0;border-radius:0 999px 999px 0;background:linear-gradient(90deg,var(--accent),var(--accent-2));transition:width .28s ease}
.quiz-body{min-height:0;padding:clamp(18px,3vw,28px);overflow:auto;overscroll-behavior:contain;scrollbar-gutter:stable;background:color-mix(in srgb,var(--paper) 56%,var(--card))}.quiz-body::-webkit-scrollbar{width:9px}.quiz-body::-webkit-scrollbar-thumb{background:var(--line);border:3px solid transparent;border-radius:999px;background-clip:padding-box}
.quiz-question-card{width:min(720px,100%);margin:0 auto}.quiz-question-meta{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:13px}.q-type{display:inline-flex;align-items:center;min-height:27px;padding:5px 10px;border:1px solid color-mix(in srgb,var(--accent) 35%,var(--line));border-radius:999px;background:var(--accent-soft);color:var(--accent-2);font-family:'JetBrains Mono',monospace;font-size:10px;font-weight:800;line-height:1.2}.q-shortcut{color:var(--ink-faint);font-family:'JetBrains Mono',monospace;font-size:9.5px}
.quiz-question-card .q-title{margin:0 0 20px;color:var(--ink);font-family:'Hind','Noto Sans Devanagari',sans-serif;font-size:clamp(19px,2.5vw,24px);font-weight:800;line-height:1.55;letter-spacing:0}
.quiz-options{display:grid;gap:11px}.quiz-option{width:100%;min-height:58px;padding:11px 13px;border:1px solid var(--line);border-radius:14px;display:grid;grid-template-columns:36px minmax(0,1fr) 28px;align-items:center;gap:12px;background:var(--card);color:var(--ink);text-align:left;cursor:pointer;box-shadow:0 2px 8px rgba(18,34,29,.035);transition:transform .15s ease,border-color .15s ease,box-shadow .15s ease,background .15s ease}.quiz-option:hover:not(:disabled){transform:translateY(-1px);border-color:var(--accent);box-shadow:0 7px 18px rgba(18,34,29,.08)}.quiz-option:focus-visible{outline:3px solid color-mix(in srgb,var(--accent) 28%,transparent);outline-offset:2px}.quiz-option:disabled{cursor:default;opacity:1}.option-key{width:36px;height:36px;border:1px solid var(--line);border-radius:10px;display:grid;place-items:center;background:var(--paper-2);color:var(--ink-soft);font-family:'JetBrains Mono',monospace;font-size:12px;font-weight:900}.option-text{font-size:15.5px;font-weight:700;line-height:1.45}.option-state{width:28px;height:28px;display:grid;place-items:center;border-radius:999px;font-size:13px}.quiz-option.selected{border-width:2px}.quiz-option.correct{border-color:var(--success);background:color-mix(in srgb,var(--success) 9%,var(--card))}.quiz-option.correct .option-key,.quiz-option.correct .option-state{border-color:color-mix(in srgb,var(--success) 45%,var(--line));background:var(--success);color:#fff}.quiz-option.wrong{border-color:var(--danger);background:color-mix(in srgb,var(--danger) 8%,var(--card))}.quiz-option.wrong .option-key,.quiz-option.wrong .option-state{border-color:color-mix(in srgb,var(--danger) 45%,var(--line));background:var(--danger);color:#fff}
.quiz-feedback{margin-top:16px;padding:14px 15px;border:1px solid var(--line);border-left-width:4px;border-radius:12px;background:var(--card)}.quiz-feedback.is-correct{border-left-color:var(--success);background:color-mix(in srgb,var(--success) 6%,var(--card))}.quiz-feedback.is-wrong{border-left-color:var(--danger);background:color-mix(in srgb,var(--danger) 5%,var(--card))}.feedback-title{display:flex;align-items:center;gap:8px;margin-bottom:5px}.is-correct .feedback-title{color:var(--success)}.is-wrong .feedback-title{color:var(--danger)}.quiz-feedback p{margin:0;color:var(--ink-soft);font-size:14px;line-height:1.65}
.quiz-foot{padding:13px 20px calc(13px + env(safe-area-inset-bottom));border-top:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;gap:12px;background:var(--card)}.quiz-nav{min-height:44px;padding:10px 16px;border-radius:12px;display:inline-flex;align-items:center;justify-content:center;gap:9px;font-size:14px;font-weight:800;cursor:pointer;transition:transform .15s ease,opacity .15s ease,box-shadow .15s ease}.quiz-nav.secondary{border:1px solid var(--line);background:var(--card);color:var(--ink)}.quiz-nav.primary{margin-left:auto;border:1px solid var(--accent);background:var(--accent);color:#fff;box-shadow:0 7px 16px color-mix(in srgb,var(--accent) 22%,transparent)}.quiz-nav:hover:not(:disabled){transform:translateY(-1px)}.quiz-nav:disabled{opacity:.42;cursor:not-allowed;box-shadow:none}
.quiz-result{width:min(620px,100%);margin:0 auto;padding:6px 0 10px;text-align:center}.result-ring{--score:0;width:148px;height:148px;margin:3px auto 20px;border-radius:50%;display:grid;place-items:center;background:conic-gradient(var(--accent) calc(var(--score)*1%),var(--line-soft) 0);position:relative}.result-ring:before{content:'';position:absolute;inset:11px;border-radius:50%;background:var(--card)}.result-ring>div{position:relative;display:grid}.result-ring strong{color:var(--ink);font-family:'JetBrains Mono',monospace;font-size:30px;line-height:1.1}.result-ring span{color:var(--ink-faint);font-size:11px;font-weight:700}.quiz-result h3{margin:0 0 7px;font-size:25px}.result-summary{margin:0;color:var(--ink-soft)}.result-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin:20px 0}.result-stats>div{padding:13px 10px;border:1px solid var(--line);border-radius:12px;background:var(--card)}.result-stats strong{display:block;color:var(--ink);font-family:'JetBrains Mono',monospace;font-size:21px}.result-stats span{color:var(--ink-faint);font-size:11px;font-weight:700}.result-note{color:var(--ink-faint);font-size:12px}.quiz-retry{min-height:46px;margin-top:9px;padding:11px 18px;border:0;border-radius:12px;background:var(--accent);color:#fff;font-weight:900;cursor:pointer;box-shadow:0 8px 18px color-mix(in srgb,var(--accent) 22%,transparent)}
@keyframes quizFadeIn{from{opacity:0}to{opacity:1}}@keyframes quizRise{from{opacity:0;transform:translateY(10px) scale(.99)}to{opacity:1;transform:none}}
@media(max-width:620px){.quiz-overlay{padding:0;align-items:end}.quiz-modal{width:100%;height:min(92dvh,860px);max-height:92dvh;border-radius:22px 22px 0 0;border-bottom:0}.quiz-head{padding:16px 16px 12px}.quiz-head h2{font-size:22px}.quiz-head p{font-size:12px}.quiz-close{width:38px;height:38px}.quiz-status{padding:8px 16px}.quiz-body{padding:18px 14px}.quiz-question-meta{margin-bottom:11px}.q-shortcut{display:none}.quiz-question-card .q-title{font-size:19px;line-height:1.5;margin-bottom:16px}.quiz-options{gap:9px}.quiz-option{min-height:55px;padding:9px 10px;grid-template-columns:34px minmax(0,1fr) 25px;gap:10px;border-radius:12px}.option-key{width:34px;height:34px}.option-text{font-size:15px}.quiz-feedback{padding:12px}.quiz-foot{padding:11px 12px calc(11px + env(safe-area-inset-bottom))}.quiz-nav{min-height:43px;padding:9px 13px}.result-ring{width:130px;height:130px}.result-stats{gap:7px}}
@media(prefers-reduced-motion:reduce){.quiz-overlay.open,.quiz-modal{animation:none}.quiz-fill,.quiz-option,.quiz-close,.quiz-nav{transition:none}}

/* =========================================================
   QUIZ V3 — compact exam workspace
   ========================================================= */
body.quiz-open{overflow:hidden}
.quiz-overlay{position:fixed!important;inset:0!important;z-index:1200!important;display:none!important;padding:20px!important;background:rgba(11,18,20,.70)!important;backdrop-filter:blur(10px)!important;-webkit-backdrop-filter:blur(10px)!important}
.quiz-overlay.open{display:grid!important;place-items:center!important}
.quiz-modal{width:min(1060px,100%)!important;height:auto!important;max-height:92dvh!important;display:grid!important;grid-template-columns:220px minmax(0,1fr)!important;grid-template-rows:minmax(0,1fr)!important;overflow:hidden!important;border:1px solid color-mix(in srgb,var(--accent) 24%,var(--line))!important;border-radius:20px!important;background:var(--card)!important;box-shadow:0 30px 90px rgba(0,0,0,.38)!important;animation:quizV3Enter .2s ease-out!important}
.quiz-sidebar{min-height:0;padding:22px 18px 18px;display:flex;flex-direction:column;background:linear-gradient(180deg,color-mix(in srgb,var(--accent) 9%,var(--paper-2)),var(--paper-2));border-right:1px solid var(--line)}
.quiz-brand{display:flex;align-items:center;gap:11px;padding-bottom:17px;border-bottom:1px solid var(--line)}
.quiz-brand-icon{width:38px;height:38px;display:grid;place-items:center;border-radius:11px;background:var(--accent);color:#fff;box-shadow:0 7px 16px color-mix(in srgb,var(--accent) 24%,transparent)}
.quiz-brand div{display:grid}.quiz-brand small{color:var(--ink-faint);font-family:'JetBrains Mono',monospace;font-size:8.5px;font-weight:800;letter-spacing:.12em}.quiz-brand strong{font-size:15px;line-height:1.25}
.quiz-side-score{display:grid;grid-template-columns:72px 1fr;align-items:center;gap:13px;padding:20px 0 16px}
.quiz-progress-ring{--progress:0;width:68px;height:68px;border-radius:50%;display:grid;place-items:center;position:relative;background:conic-gradient(var(--accent) calc(var(--progress)*1%),var(--line) 0)}
.quiz-progress-ring:before{content:'';position:absolute;inset:6px;border-radius:50%;background:var(--paper-2)}
.quiz-progress-ring strong{position:relative;color:var(--ink);font-family:'JetBrains Mono',monospace;font-size:13px}.quiz-side-score>div:last-child{display:grid}.quiz-side-score>div:last-child strong{font-family:'JetBrains Mono',monospace;font-size:17px}.quiz-side-score>div:last-child span{color:var(--ink-faint);font-size:11px;font-weight:700}
.quiz-legend{display:grid;grid-template-columns:1fr 1fr;gap:7px 9px;margin-bottom:12px;color:var(--ink-faint);font-size:9.5px;font-weight:700}.quiz-legend span{display:flex;align-items:center;gap:6px}.legend-dot{width:8px;height:8px;border-radius:3px;border:1px solid var(--line);background:var(--card)}.legend-dot.current{border-color:var(--accent);background:var(--accent)}.legend-dot.answered{border-color:var(--success);background:color-mix(in srgb,var(--success) 72%,white)}
.quiz-palette{min-height:0;overflow:auto;display:grid;grid-template-columns:repeat(5,1fr);align-content:start;gap:6px;padding:2px 3px 8px 0;scrollbar-width:thin}
.quiz-palette-btn{aspect-ratio:1;border:1px solid var(--line);border-radius:8px;background:var(--card);color:var(--ink-soft);font-family:'JetBrains Mono',monospace;font-size:10px;font-weight:800;cursor:pointer;transition:.15s ease}.quiz-palette-btn:hover{border-color:var(--accent);color:var(--accent)}.quiz-palette-btn.answered{border-color:color-mix(in srgb,var(--success) 55%,var(--line));background:color-mix(in srgb,var(--success) 12%,var(--card));color:var(--success)}.quiz-palette-btn.current{border-color:var(--accent);background:var(--accent);color:#fff;box-shadow:0 4px 10px color-mix(in srgb,var(--accent) 22%,transparent)}
.quiz-side-note{margin:auto 0 0;padding-top:14px;border-top:1px solid var(--line);color:var(--ink-faint);font-size:9.5px;line-height:1.5}.quiz-side-note i{color:var(--accent);margin-right:5px}
.quiz-workspace{min-width:0;min-height:0;display:grid;grid-template-rows:auto auto 4px minmax(0,1fr) auto;background:var(--card)}
.quiz-head{padding:17px 20px 13px!important;display:flex!important;align-items:flex-start!important;justify-content:space-between!important;gap:16px!important;border:0!important;background:var(--card)!important}
.quiz-heading-copy{min-width:0}.quiz-eyebrow{display:block!important;margin:0 0 4px!important;color:var(--accent)!important;font-family:'JetBrains Mono',monospace!important;font-size:9px!important;font-weight:900!important;letter-spacing:.08em!important}.quiz-head h2{margin:0!important;font-size:21px!important;line-height:1.22!important}.quiz-head p{margin:4px 0 0!important;color:var(--ink-faint)!important;font-size:11.5px!important;line-height:1.4!important}.quiz-close{width:36px!important;height:36px!important;border:1px solid var(--line)!important;border-radius:10px!important;background:var(--card)!important;color:var(--ink-soft)!important;box-shadow:none!important}.quiz-close:hover{border-color:var(--danger)!important;color:var(--danger)!important;transform:none!important}
.quiz-status{padding:8px 20px!important;border-top:1px solid var(--line-soft)!important;background:var(--paper)!important;font-size:10px!important}.quiz-counter{font-weight:900!important}.quiz-bar{height:4px!important}.quiz-fill{border-radius:0!important;background:var(--accent)!important}
.quiz-body{min-height:0!important;overflow:auto!important;padding:20px 24px 22px!important;background:var(--card)!important;scrollbar-gutter:auto!important}.quiz-question-card{width:100%!important;max-width:760px!important;margin:0 auto!important}.quiz-question-meta{margin:0 0 10px!important}.q-type{min-height:24px!important;margin:0!important;padding:4px 8px!important;border-radius:7px!important;background:var(--accent-soft)!important;font-size:9px!important;letter-spacing:.02em!important}.q-shortcut{display:none!important}.quiz-question-card .q-title{margin:0 0 16px!important;font-size:clamp(18px,2vw,22px)!important;line-height:1.48!important;font-weight:800!important}.quiz-options{gap:9px!important}.quiz-option{min-height:50px!important;padding:8px 11px!important;grid-template-columns:32px minmax(0,1fr) 24px!important;gap:10px!important;border-radius:10px!important;box-shadow:none!important}.quiz-option:hover:not(:disabled){transform:none!important;border-color:var(--accent)!important;background:color-mix(in srgb,var(--accent) 4%,var(--card))!important;box-shadow:none!important}.option-key{width:32px!important;height:32px!important;border-radius:8px!important;font-size:10px!important}.option-text{font-size:14.5px!important;font-weight:700!important;line-height:1.4!important}.option-state{width:24px!important;height:24px!important;font-size:11px!important}.quiz-option.selected{border-width:1px!important}.quiz-option.correct{border-width:1.5px!important}.quiz-option.wrong{border-width:1.5px!important}
.quiz-feedback{margin-top:12px!important;padding:11px 12px!important;border-radius:9px!important;border-left-width:3px!important}.feedback-title{margin-bottom:3px!important;font-size:13px!important}.quiz-feedback p{font-size:12.5px!important;line-height:1.55!important}
.quiz-foot{padding:11px 18px!important;display:grid!important;grid-template-columns:auto 1fr auto!important;align-items:center!important;background:var(--paper)!important}.quiz-foot-hint{text-align:center;color:var(--ink-faint);font-size:9.5px}.quiz-nav{min-height:39px!important;padding:8px 13px!important;border-radius:9px!important;font-size:12.5px!important;box-shadow:none!important}.quiz-nav.primary{box-shadow:0 5px 12px color-mix(in srgb,var(--accent) 18%,transparent)!important}
.quiz-result{padding:8px 0!important}.result-ring{width:116px!important;height:116px!important;margin-bottom:14px!important}.result-ring strong{font-size:25px!important}.quiz-result h3{font-size:21px!important}.result-stats{margin:15px 0!important}.quiz-retry{min-height:41px!important;border-radius:9px!important}
@keyframes quizV3Enter{from{opacity:0;transform:translateY(8px) scale(.99)}to{opacity:1;transform:none}}
@media(max-width:760px){.quiz-overlay{padding:0!important;align-items:end!important}.quiz-modal{width:100%!important;max-height:94dvh!important;grid-template-columns:1fr!important;border-radius:18px 18px 0 0!important;border-bottom:0!important}.quiz-sidebar{display:none!important}.quiz-head{padding:14px 14px 10px!important}.quiz-head h2{font-size:19px!important}.quiz-head p{font-size:11px!important}.quiz-status{padding:7px 14px!important}.quiz-body{padding:16px 13px 18px!important}.quiz-question-card .q-title{font-size:18px!important;margin-bottom:14px!important}.quiz-option{min-height:49px!important;padding:8px 9px!important}.option-text{font-size:14px!important}.quiz-foot{padding:9px 10px calc(9px + env(safe-area-inset-bottom))!important;grid-template-columns:auto 1fr auto!important}.quiz-foot-hint{font-size:0}.quiz-foot-hint:after{content:'1–4';font-size:9px}.quiz-nav span{display:inline}}
@media(max-width:390px){.quiz-head p{display:none!important}.quiz-question-card .q-title{font-size:17px!important}.quiz-option{grid-template-columns:30px minmax(0,1fr) 22px!important}.option-key{width:30px!important;height:30px!important}.quiz-nav{padding:8px 10px!important}}

/* =========================================================
   PAGE UI/UX REFINEMENT V4 — shared across World History
   ========================================================= */
:root{
  --content-w:920px;
  --header-h:54px;
  --radius-sm:10px;
  --radius-md:16px;
  --radius-lg:22px;
  --surface-elevated:color-mix(in srgb,var(--card) 96%,var(--paper));
  --accent-ring:color-mix(in srgb,var(--accent) 18%,transparent);
}
body{
  background:
    radial-gradient(circle at 12% 0%,color-mix(in srgb,var(--accent) 5%,transparent),transparent 28rem),
    var(--paper);
}
::selection{background:color-mix(in srgb,var(--accent) 22%,transparent);color:var(--ink)}
.skip-link{position:fixed;left:16px;top:-60px;z-index:2000;padding:9px 13px;border-radius:10px;background:var(--accent);color:#fff;text-decoration:none;font-weight:800;transition:top .2s}.skip-link:focus{top:12px}

.progress-shell{
  min-height:var(--header-h);
  padding:8px clamp(10px,2vw,20px);
  gap:8px;
  box-shadow:0 1px 0 var(--line-soft);
}
.progress-shell::after{
  content:"";position:absolute;left:0;bottom:-1px;height:2px;
  width:calc(var(--reading-progress,0) * 1%);
  background:linear-gradient(90deg,var(--accent),var(--accent-2));
  transition:width .08s linear;
}
.topbtn{width:36px;height:36px;border-radius:11px;box-shadow:0 1px 2px rgba(0,0,0,.03)}
.topbtn:focus-visible,.toc-tab:focus-visible,.toc-link:focus-visible,.complete-btn:focus-visible,.h2-btn:focus-visible,.card-action:focus-visible{outline:3px solid var(--accent-ring);outline-offset:2px}
.topbar-title{font-size:13px;letter-spacing:.01em}
.section-indicator{max-width:420px;border-color:var(--line);background:var(--paper);font-size:11.5px}
.progress-label{min-width:108px;font-size:11px}

.app{grid-template-columns:286px minmax(0,1fr)}
.sidebar{
  top:var(--header-h);height:calc(100vh - var(--header-h));
  padding:18px 14px 24px;background:color-mix(in srgb,var(--paper-2) 90%,var(--card));
}
.brand-card{margin-bottom:12px;padding:15px 15px 14px;border-radius:15px;box-shadow:none;background:linear-gradient(145deg,var(--card),color-mix(in srgb,var(--accent) 4%,var(--card)))}
.brand-card::before{content:"";display:block;width:34px;height:4px;margin-bottom:11px;border-radius:99px;background:var(--accent)}
.brand-card strong{font-size:17px}.brand-card span{font-size:11.5px}
.side-link{justify-content:flex-start;margin:0 0 12px;padding:9px 11px;border-radius:11px;background:transparent}
.toc-toolbar{padding:4px;border:1px solid var(--line-soft);border-radius:12px;background:var(--card);gap:3px}
.toc-tab{border:0;border-radius:8px;padding:7px 4px;background:transparent;font-size:11px}
.toc-tab.active{box-shadow:0 3px 10px color-mix(in srgb,var(--accent) 18%,transparent)}
.toc-label{margin:18px 8px 8px}
.toc-list{gap:4px}
.toc-link{position:relative;padding:9px 10px 9px 12px;border-radius:9px;font-size:12.5px}
.toc-link::before{content:"";position:absolute;left:0;top:10px;bottom:10px;width:3px;border-radius:99px;background:transparent}
.toc-link.active{background:var(--card);border-color:var(--line-soft);box-shadow:0 2px 8px rgba(0,0,0,.035)}
.toc-link.active::before{background:var(--accent)}

.reader{width:min(var(--content-w),100%);padding:32px clamp(16px,4vw,38px) 96px}
.page-breadcrumb{margin-bottom:15px;font-size:11.5px}
.hero{
  position:relative;overflow:hidden;margin:0 0 24px;padding:28px clamp(20px,4vw,34px);
  border:1px solid var(--line);border-radius:var(--radius-lg);background:linear-gradient(135deg,var(--card),color-mix(in srgb,var(--accent) 6%,var(--card)));box-shadow:var(--shadow);
}
.hero::after{content:"";position:absolute;right:-64px;top:-72px;width:190px;height:190px;border-radius:50%;border:34px solid color-mix(in srgb,var(--accent) 5%,transparent);pointer-events:none}
.hero .eyebrow{position:relative;z-index:1;font-size:10.5px;letter-spacing:1.5px}
.hero h1{position:relative;z-index:1;margin:7px 0 10px;padding:0;border:0;font-size:clamp(30px,5vw,48px);max-width:760px}
.hero h1::after{content:"";display:block;width:72px;height:4px;margin-top:14px;border-radius:99px;background:var(--accent)}
.hero p{position:relative;z-index:1;max-width:760px;font-size:16.5px;line-height:1.75;text-align:left}
.hero-meta{position:relative;z-index:1;margin-top:17px;gap:8px}
.hero-meta span{padding:6px 10px;background:color-mix(in srgb,var(--card) 86%,transparent);font-size:11px}

.card{
  margin:18px 0;padding:clamp(20px,3vw,30px);
  border-color:var(--line-soft);border-radius:var(--radius-lg);box-shadow:0 6px 22px rgba(22,39,34,.055);
}
.card:hover{border-color:color-mix(in srgb,var(--accent) 24%,var(--line));box-shadow:0 10px 30px rgba(22,39,34,.075)}
.card h2{position:relative;margin:0 0 22px;padding-bottom:15px;border-bottom:1px solid var(--line-soft);font-size:clamp(21px,3vw,27px);line-height:1.38}
.idx{width:35px;height:35px;border-radius:10px;font-size:12px;box-shadow:0 5px 12px color-mix(in srgb,var(--accent) 18%,transparent)}
.h2-btn{width:33px;height:33px;background:var(--card);font-size:13px}
.card h3{margin:24px 0 9px;padding-left:13px;font-size:19px;line-height:1.5;position:relative}
.card h3::before{content:"";position:absolute;left:0;top:.38em;width:4px;height:1.1em;border-radius:99px;background:var(--accent)}
.card>p{margin:8px 0 13px;color:var(--ink-soft)}
.card ul{list-style:none;padding-left:0;margin:8px 0 16px}
.card li{position:relative;margin:0;padding:8px 0 8px 25px;border-bottom:1px dashed var(--line-soft);line-height:1.72}
.card li:last-child{border-bottom:0}
.card li::before{content:"";position:absolute;left:4px;top:1.18em;width:7px;height:7px;border:2px solid var(--accent);border-radius:50%;background:var(--card)}
.card li strong{font-weight:700}
.plain-note{padding:11px 13px;border-radius:10px;background:var(--accent-soft);border-left:3px solid var(--accent);font-size:14px!important}

.table-wrap{margin:15px 0 20px;border-radius:14px;box-shadow:inset 0 0 0 1px var(--line-soft);scrollbar-width:thin}
table{font-size:14px;line-height:1.55}
th,td{padding:11px 13px}
th{position:sticky;top:0;z-index:1;background:var(--paper-2);font-size:12.5px;letter-spacing:.01em}
tbody tr:nth-child(even){background:color-mix(in srgb,var(--paper-2) 46%,transparent)}
tbody tr:hover{background:var(--accent-soft)}
.complete-row{margin-top:22px;padding-top:17px}
.complete-btn{display:inline-flex;align-items:center;gap:8px;padding:8px 13px;border-radius:10px;background:var(--card);font-size:12.5px}
.complete-btn::before{content:"✓";display:grid;place-items:center;width:20px;height:20px;border:1px solid var(--line);border-radius:6px;color:transparent;font-size:11px}
.complete-btn.done::before{border-color:rgba(255,255,255,.45);color:#fff}
.section-meta{padding:5px 8px;border-radius:8px;background:var(--paper);font-size:10.5px}

/* Category / home page */
.category-main{background:transparent}
.category-reader{width:min(1100px,100%);padding:34px clamp(16px,4vw,42px) 90px}
.category-hero{margin:0 0 22px;padding:30px clamp(20px,4vw,34px);border:1px solid var(--line);border-radius:var(--radius-lg);background:linear-gradient(135deg,var(--card),color-mix(in srgb,var(--accent) 5%,var(--card)));box-shadow:var(--shadow)}
.category-hero h1{margin:7px 0 10px;padding:0;border:0;font-size:clamp(34px,5vw,52px)}
.category-hero p{max-width:820px;font-size:16.5px;text-align:left}
.category-stats span{background:var(--paper);font-size:11px}
.student-flow{gap:12px;margin:18px 0 26px}
.student-flow article{border-radius:15px;box-shadow:none;background:var(--card);padding:16px}
.category-grid{gap:15px}
.category-card{padding:20px;border-radius:18px;box-shadow:0 5px 18px rgba(22,39,34,.05);transition:transform .18s ease,border-color .18s ease,box-shadow .18s ease}
.category-card:not(.disabled):hover{transform:translateY(-3px);border-color:color-mix(in srgb,var(--accent) 35%,var(--line));box-shadow:0 12px 30px rgba(22,39,34,.09)}
.card-icon{border-radius:14px;background:var(--accent-soft);color:var(--accent)}
.category-card h2{font-size:21px}.category-card p{font-size:14px;line-height:1.65}.card-action{font-size:13px}
#categorySearch{display:block;width:100%;margin:8px 0 4px;box-shadow:none;border-radius:12px;padding:12px 14px;font:inherit;color:var(--ink)}
.help-text{margin:0 0 16px;color:var(--ink-faint);font-size:11px}
.roadmap-box,.category-note{border-radius:18px;box-shadow:none}

.back-to-top{position:fixed;right:20px;bottom:20px;z-index:45;width:42px;height:42px;border:1px solid var(--line);border-radius:13px;background:var(--card);color:var(--accent);box-shadow:var(--shadow-lg);cursor:pointer;display:grid;place-items:center;opacity:0;pointer-events:none;transform:translateY(8px);transition:.2s ease}
.back-to-top.visible{opacity:1;pointer-events:auto;transform:none}
.back-to-top:hover{background:var(--accent);color:#fff;border-color:var(--accent)}

@media(max-width:900px){
  .app{grid-template-columns:1fr}.sidebar{position:fixed;left:0;top:var(--header-h);z-index:80;width:min(320px,88vw);transform:translateX(-104%);box-shadow:18px 0 50px rgba(0,0,0,.22)}.sidebar.open{transform:translateX(0)}
  #sidebar-scrim{position:fixed;inset:var(--header-h) 0 0;z-index:70;background:rgba(7,16,15,.45);backdrop-filter:blur(3px)}#sidebar-scrim.open{display:block}
  main{grid-row:2}.mobile-only{display:grid!important}.section-indicator{flex:1}.topbar-title{display:none}
}
@media(min-width:901px){.mobile-only{display:none!important}}
@media(max-width:640px){
  :root{--fs-base:16.5px;--header-h:50px}
  .progress-shell{padding:6px 8px}.topbtn{width:34px;height:34px}.section-indicator{font-size:10.5px;padding:5px 8px}.progress-label{min-width:78px;font-size:9.5px}
  .reader,.category-reader{padding:18px 12px 80px}.page-breadcrumb{margin:0 4px 12px}
  .hero,.category-hero{padding:22px 18px;border-radius:18px}.hero h1,.category-hero h1{font-size:29px}.hero p,.category-hero p{font-size:15px;line-height:1.7}.hero-meta span,.category-stats span{font-size:10px;padding:5px 8px}
  .card{margin:14px 0;padding:19px 16px;border-radius:17px}.card h2{font-size:20px;gap:8px;padding-bottom:13px}.idx{width:32px;height:32px}.card h3{font-size:18px;margin-top:21px}.card li{padding:7px 0 7px 22px;line-height:1.68}
  .complete-row{align-items:flex-start;flex-direction:column}.section-meta{align-self:flex-end;margin-top:-38px}
  .table-wrap{margin-left:-3px;margin-right:-3px;border-radius:11px}table{min-width:650px;font-size:13px}
  .student-flow{grid-template-columns:1fr}.category-grid{grid-template-columns:1fr}.category-card{padding:17px}
  .back-to-top{right:12px;bottom:12px;width:40px;height:40px}
}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important;animation:none!important}}
@media print{.progress-shell,.sidebar,#sidebar-scrim,.complete-row,.back-to-top,.quiz-overlay{display:none!important}.app{display:block}.reader{width:100%;padding:0}.hero,.card{box-shadow:none;break-inside:avoid}.card{border-color:#bbb}body{background:#fff;color:#000}}


/* ---------- SEO, trust pages and AdSense-safe placements ---------- */
.ad-container{display:none;margin:28px auto;max-width:970px;min-height:0;overflow:hidden;text-align:center;clear:both}
.ad-container.ad-enabled{display:block;min-height:90px;padding:10px 0;border-top:1px solid var(--line-soft);border-bottom:1px solid var(--line-soft)}
.ad-container.ad-enabled::before{content:"Advertisement";display:block;margin-bottom:6px;color:var(--ink-faint);font:600 9px/1.2 'JetBrains Mono',monospace;letter-spacing:.08em;text-transform:uppercase}
.study-article{display:contents}
.article-meta{display:flex;flex-wrap:wrap;gap:8px 18px;align-items:center;margin:28px 0 12px;padding:16px 18px;border:1px solid var(--line);border-radius:12px;background:var(--paper-2);color:var(--ink-soft);font-size:13px}
.article-meta a{margin-left:auto;color:var(--accent-2);font-weight:700;text-decoration:none}
.related-nav{width:min(var(--reader-w),calc(100% - 32px));margin:20px auto 40px}
.related-nav a{display:flex;justify-content:space-between;gap:18px;padding:18px 20px;border:1px solid var(--line);border-radius:14px;background:var(--card);color:var(--ink);text-decoration:none;box-shadow:var(--shadow)}
.related-nav span{color:var(--ink-soft)}.related-nav strong{color:var(--accent-2)}
.site-footer{margin-top:52px;border-top:1px solid var(--line);background:var(--paper-2);color:var(--ink-soft)}
.site-footer-inner{width:min(1080px,100%);margin:auto;padding:30px 24px 22px;display:grid;grid-template-columns:minmax(220px,1fr) auto;gap:22px 42px;align-items:start}
.site-footer strong{color:var(--ink);font-size:17px}.site-footer p{margin:6px 0 0;font-size:13px;line-height:1.65}
.site-footer nav{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:10px 18px}.site-footer a{color:var(--ink-soft);font-size:13px;font-weight:650;text-decoration:none}.site-footer a:hover{color:var(--accent-2);text-decoration:underline}
.footer-copy{grid-column:1/-1;padding-top:14px;border-top:1px solid var(--line-soft);font-size:11px!important}
.seo-content-block{margin:28px 0;padding:24px;border:1px solid var(--line);border-radius:16px;background:var(--card);box-shadow:var(--shadow)}
.seo-content-block h2{margin:0 0 12px;font-size:clamp(21px,3vw,28px)}.seo-content-block p{margin:8px 0;color:var(--ink-soft);line-height:1.8}
.legal-main{min-height:70vh;padding:48px 22px}.legal-reader{width:min(780px,100%);margin:auto}.legal-reader h1{font-size:clamp(32px,5vw,48px);line-height:1.2}.legal-card{margin-top:22px;padding:26px;border:1px solid var(--line);border-radius:16px;background:var(--card);box-shadow:var(--shadow)}.legal-card h2{margin-top:26px;font-size:23px}.legal-card h2:first-child{margin-top:0}.legal-card p,.legal-card li{color:var(--ink-soft);line-height:1.8}.legal-card a{color:var(--accent-2)}
@media(max-width:700px){.site-footer-inner{grid-template-columns:1fr}.site-footer nav{justify-content:flex-start}.article-meta a{width:100%;margin-left:0}.related-nav{width:calc(100% - 24px)}.ad-container.ad-enabled{margin:20px 0;min-height:70px}}
@media print{.ad-container,.site-footer,.related-nav,.article-meta{display:none!important}}

/* Quiz result review map */
.quiz-palette.is-result-map .quiz-palette-btn{position:relative;color:#fff;border-width:1px;box-shadow:none}
.quiz-palette.is-result-map .quiz-palette-btn.correct{background:color-mix(in srgb,var(--success) 82%,#13211d);border-color:color-mix(in srgb,var(--success) 90%,white);color:#fff}
.quiz-palette.is-result-map .quiz-palette-btn.wrong{background:color-mix(in srgb,var(--danger) 84%,#251415);border-color:color-mix(in srgb,var(--danger) 88%,white);color:#fff;box-shadow:0 0 0 1px color-mix(in srgb,var(--danger) 18%,transparent)}
.quiz-palette.is-result-map .quiz-palette-btn.wrong:hover{transform:translateY(-1px);box-shadow:0 5px 14px color-mix(in srgb,var(--danger) 24%,transparent)}
.quiz-palette.is-result-map .quiz-palette-btn.correct:hover{transform:translateY(-1px);box-shadow:0 5px 14px color-mix(in srgb,var(--success) 20%,transparent)}
.quiz-palette.is-result-map .quiz-palette-btn.current-review{outline:2px solid #fff;outline-offset:2px;box-shadow:0 0 0 4px color-mix(in srgb,var(--accent) 45%,transparent)}
.legend-dot.result-correct{background:var(--success);border-color:var(--success)}
.legend-dot.result-wrong{background:var(--danger);border-color:var(--danger)}
.legend-dot.review-current{background:transparent;border:2px solid var(--accent)}
.result-review-help{max-width:660px;margin:14px auto 18px;padding:12px 14px;display:flex;align-items:flex-start;gap:10px;text-align:left;border:1px solid color-mix(in srgb,var(--accent) 30%,var(--line));border-radius:11px;background:color-mix(in srgb,var(--accent) 7%,var(--card));color:var(--ink-soft)}
.result-review-help i{margin-top:3px;color:var(--accent)}
.result-review-help p{margin:0;font-size:12.5px;line-height:1.55}
.result-actions{display:flex;justify-content:center;align-items:center;gap:10px;flex-wrap:wrap}
.quiz-review-wrong,.quiz-retry{min-height:42px;padding:9px 15px;border-radius:9px;font-weight:800;cursor:pointer}
.quiz-review-wrong{border:1px solid color-mix(in srgb,var(--danger) 55%,var(--line));background:color-mix(in srgb,var(--danger) 12%,var(--card));color:var(--danger)}
.quiz-review-wrong:hover{background:color-mix(in srgb,var(--danger) 18%,var(--card));transform:translateY(-1px)}
.perfect-score-note{display:inline-flex;align-items:center;gap:8px;margin:0;padding:10px 14px;border-radius:9px;background:color-mix(in srgb,var(--success) 12%,var(--card));color:var(--success);font-weight:800}
.review-banner{display:flex;align-items:flex-start;gap:10px;margin-bottom:14px;padding:11px 12px;border-radius:10px;border:1px solid var(--line)}
.review-banner>i{margin-top:2px;font-size:17px}.review-banner>div{display:grid;gap:2px}.review-banner strong{font-size:13.5px}.review-banner span{color:var(--ink-faint);font-size:11px;line-height:1.45}
.review-banner.is-correct{border-color:color-mix(in srgb,var(--success) 45%,var(--line));background:color-mix(in srgb,var(--success) 9%,var(--card));color:var(--success)}
.review-banner.is-wrong{border-color:color-mix(in srgb,var(--danger) 45%,var(--line));background:color-mix(in srgb,var(--danger) 9%,var(--card));color:var(--danger)}
.review-count{color:var(--danger);font-family:'JetBrains Mono',monospace;font-size:10px;font-weight:800}
.quiz-review-card .quiz-option:disabled{opacity:1;cursor:default}
@media(max-width:760px){.result-actions{align-items:stretch;flex-direction:column}.quiz-review-wrong,.quiz-retry{width:100%}.result-review-help{margin-inline:0}.quiz-review-card .review-banner span{display:none}}

/* High-yield exam event cards */
.exam-sequence{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px;margin:16px 0 18px}.exam-sequence-compact{grid-template-columns:repeat(3,minmax(0,1fr))}.exam-sequence-four{grid-template-columns:repeat(4,minmax(0,1fr))}.sequence-step{min-width:0;padding:15px 15px 14px;border:1px solid var(--line);border-top:3px solid var(--accent);border-radius:14px;background:var(--card);box-shadow:var(--shadow)}.sequence-year{display:inline-flex;align-items:center;min-height:26px;padding:3px 9px;border-radius:999px;background:var(--accent-soft);color:var(--accent-2);font-family:'JetBrains Mono',monospace;font-size:11px;font-weight:900;line-height:1.2}.sequence-step h4{margin:10px 0 6px;color:var(--ink);font-size:16px;line-height:1.35}.sequence-step p{margin:0;color:var(--ink-soft);font-size:14px;line-height:1.62}.civil-war-causes .fact{border-top:3px solid var(--accent)}.civil-war-causes .fact p{margin:7px 0 0;color:var(--ink-soft);font-size:14px;line-height:1.6}@media(max-width:980px){.exam-sequence-four{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:760px){.exam-sequence,.exam-sequence-compact,.exam-sequence-four{grid-template-columns:1fr}.sequence-step{padding:14px}.sequence-step h4{font-size:15px}}


/* ---------- American chapter: readable responsive tables ---------- */
.exam-table-wrap{
  overflow:auto;
  border:1px solid var(--line);
  border-radius:16px;
  margin:18px 0 22px;
  background:var(--card);
  box-shadow:0 8px 26px rgba(28,45,39,.06);
  scrollbar-width:thin;
  scrollbar-color:var(--line) transparent;
}
.exam-table-wrap::-webkit-scrollbar{height:9px;width:9px}
.exam-table-wrap::-webkit-scrollbar-thumb{background:var(--line);border:2px solid transparent;border-radius:999px;background-clip:padding-box}
.exam-table{
  width:100%;
  min-width:0;
  border-collapse:separate;
  border-spacing:0;
  table-layout:auto;
  font-size:15px;
  line-height:1.65;
}
.exam-table th,
.exam-table td{
  padding:14px 16px;
  border:0;
  border-right:1px solid var(--line-soft);
  border-bottom:1px solid var(--line-soft);
  text-align:left;
  vertical-align:top;
}
.exam-table th:last-child,
.exam-table td:last-child{border-right:0}
.exam-table tbody tr:last-child td{border-bottom:0}
.exam-table thead th{
  position:sticky;
  top:0;
  z-index:2;
  background:color-mix(in srgb,var(--paper-2) 94%,var(--card));
  color:var(--ink);
  font-size:13px;
  font-weight:900;
  letter-spacing:.01em;
  box-shadow:0 1px 0 var(--line);
}
.exam-table tbody tr:nth-child(even){background:color-mix(in srgb,var(--paper-2) 38%,transparent)}
.exam-table tbody tr{transition:background .16s ease}
.exam-table tbody tr:hover{background:var(--accent-soft)}
.exam-table td:first-child{
  width:24%;
  min-width:150px;
  color:var(--accent-2);
  font-weight:900;
  background:color-mix(in srgb,var(--accent-soft) 48%,transparent);
}
.exam-table.table-cols-3 td:first-child{width:18%;min-width:130px}
.exam-table.table-cols-3 td:nth-child(2){width:28%;min-width:190px}
.table-cell-lines{
  display:grid;
  gap:0;
  color:var(--ink-soft);
}
.table-fact-line{
  position:relative;
  display:block;
  padding-left:16px;
  line-height:1.68;
}
.table-fact-line::before{
  content:"";
  position:absolute;
  left:1px;
  top:.72em;
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--accent);
  box-shadow:0 0 0 3px var(--accent-soft);
}
.table-fact-line + .table-fact-line{
  margin-top:9px;
  padding-top:9px;
  border-top:1px dashed var(--line);
}
.table-fact-line + .table-fact-line::before{top:1.45em}
.table-fact-line strong{color:var(--ink)}

/* ---------- Compact chapter-end information and navigation ---------- */
.chapter-end{
  display:grid;
  gap:14px;
  margin:30px 0 0;
}
.chapter-meta-bar{
  display:flex;
  align-items:center;
  gap:14px 24px;
  flex-wrap:wrap;
  padding:16px 18px;
  border:1px solid var(--line);
  border-radius:16px;
  background:linear-gradient(135deg,color-mix(in srgb,var(--accent-soft) 72%,var(--card)),var(--card));
  box-shadow:var(--shadow);
}
.chapter-meta-item{display:flex;align-items:center;gap:10px;min-width:180px}
.chapter-meta-icon{
  width:38px;
  height:38px;
  flex:0 0 38px;
  display:grid;
  place-items:center;
  border:1px solid color-mix(in srgb,var(--accent) 28%,var(--line));
  border-radius:11px;
  background:var(--card);
  color:var(--accent-2);
}
.chapter-meta-copy{display:grid;gap:1px;line-height:1.3}
.chapter-meta-copy small{color:var(--ink-faint);font-size:10.5px;font-weight:800;letter-spacing:.04em;text-transform:uppercase}
.chapter-meta-copy strong{font-size:14px;color:var(--ink)}
.chapter-meta-badge{
  margin-left:auto;
  display:inline-flex;
  align-items:center;
  gap:7px;
  padding:7px 11px;
  border:1px solid color-mix(in srgb,var(--accent) 28%,var(--line));
  border-radius:999px;
  background:var(--card);
  color:var(--accent-2);
  font-size:12px;
  font-weight:900;
  white-space:nowrap;
}
.chapter-navigation{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.chapter-nav-card{
  min-width:0;
  min-height:88px;
  display:flex;
  align-items:center;
  gap:14px;
  padding:17px 18px;
  border:1px solid var(--line);
  border-radius:16px;
  background:var(--card);
  color:var(--ink);
  text-decoration:none;
  box-shadow:var(--shadow);
  transition:transform .16s ease,border-color .16s ease,box-shadow .16s ease,background .16s ease;
}
.chapter-nav-card:hover{
  transform:translateY(-2px);
  border-color:color-mix(in srgb,var(--accent) 55%,var(--line));
  background:color-mix(in srgb,var(--accent-soft) 50%,var(--card));
  box-shadow:var(--shadow-lg);
}
.chapter-nav-index{justify-content:space-between;text-align:right}
.chapter-nav-copy{display:grid;gap:3px;min-width:0}
.chapter-nav-copy small{color:var(--ink-faint);font-size:11px;font-weight:800;letter-spacing:.03em}
.chapter-nav-copy strong{overflow:hidden;color:var(--accent-2);font-size:17px;line-height:1.35;text-overflow:ellipsis}
.chapter-nav-icon{
  width:40px;
  height:40px;
  flex:0 0 40px;
  display:grid;
  place-items:center;
  border-radius:12px;
  background:var(--accent-soft);
  color:var(--accent-2);
}

@media(max-width:720px){
  .exam-table-wrap{
    overflow:visible;
    border:0;
    border-radius:0;
    background:transparent;
    box-shadow:none;
    margin:16px 0 20px;
  }
  .exam-table,
  .exam-table tbody,
  .exam-table tr,
  .exam-table td{display:block;width:100%;min-width:0!important}
  .exam-table thead{
    position:absolute!important;
    width:1px!important;
    height:1px!important;
    padding:0!important;
    margin:-1px!important;
    overflow:hidden!important;
    clip:rect(0,0,0,0)!important;
    white-space:nowrap!important;
    border:0!important;
  }
  .exam-table tbody{display:grid;gap:12px}
  .exam-table tbody tr{
    overflow:hidden;
    margin:0;
    border:1px solid var(--line);
    border-radius:14px;
    background:var(--card)!important;
    box-shadow:var(--shadow);
  }
  .exam-table td{
    display:grid;
    grid-template-columns:minmax(92px,30%) minmax(0,1fr);
    gap:12px;
    padding:12px 14px;
    border:0;
    border-bottom:1px solid var(--line-soft);
    color:var(--ink-soft);
  }
  .exam-table td::before{
    content:attr(data-label);
    color:var(--ink-faint);
    font-size:10.5px;
    font-weight:900;
    letter-spacing:.04em;
    line-height:1.4;
    text-transform:uppercase;
  }
  .exam-table td:first-child{
    display:grid;
    grid-template-columns:minmax(92px,30%) minmax(0,1fr);
    width:100%;
    padding:12px 14px;
    background:var(--accent-soft);
    color:var(--accent-2);
  }
  .exam-table td:last-child{border-bottom:0}
  .table-cell-lines{min-width:0}
  .table-fact-line{padding-left:14px;font-size:14px;line-height:1.65}
  .table-fact-line + .table-fact-line{margin-top:7px;padding-top:7px}
  .chapter-end{margin-top:22px;gap:12px}
  .chapter-meta-bar{display:grid;grid-template-columns:1fr 1fr;gap:14px;padding:15px}
  .chapter-meta-item{min-width:0;align-items:flex-start}
  .chapter-meta-icon{width:34px;height:34px;flex-basis:34px}
  .chapter-meta-copy strong{font-size:13px}
  .chapter-meta-badge{grid-column:1/-1;margin-left:0;justify-content:center;width:100%}
  .chapter-navigation{grid-template-columns:1fr}
  .chapter-nav-card{min-height:76px;padding:14px 15px}
  .chapter-nav-copy strong{font-size:15.5px}
}
@media(max-width:430px){
  .exam-table td,
  .exam-table td:first-child{grid-template-columns:1fr;gap:5px}
  .exam-table td::before{font-size:9.5px}
  .chapter-meta-bar{grid-template-columns:1fr}
  .chapter-meta-badge{grid-column:auto}
}
@media print{
  .exam-table-wrap{overflow:visible;box-shadow:none}
  .exam-table{min-width:0;font-size:11px}
  .exam-table thead{display:table-header-group!important;position:static!important;width:auto!important;height:auto!important;clip:auto!important;white-space:normal!important}
  .exam-table tbody{display:table-row-group!important}
  .exam-table tr{display:table-row!important;box-shadow:none!important}
  .exam-table td,.exam-table th{display:table-cell!important;padding:7px 8px!important}
  .exam-table td::before{display:none!important}
  .chapter-end{display:none!important}
}


/* ---------- Unified footer + responsive page shell refinement ---------- */
html,body{max-width:100%;overflow-x:clip}
img,svg,video,canvas{max-width:100%}

/* Let the footer follow the actual content instead of forcing an empty viewport. */
.app{min-height:0}
.category-page{min-height:0}
.reader{padding-bottom:38px}
.category-main{padding-bottom:44px}

.world-history-footer{
  margin-top:0;
  background:color-mix(in srgb,var(--paper-2) 96%,var(--card));
}
.world-history-footer .unified-site-footer-inner{
  width:min(1120px,100%);
  padding-top:30px;
}
.world-history-footer .unified-site-footer-brand strong{
  font-family:'Poppins','Hind',sans-serif;
  letter-spacing:-.2px;
}
.world-history-footer .unified-site-footer-brand p{max-width:360px}
.world-history-footer h2{
  color:var(--ink-faint);
  font-family:'JetBrains Mono',monospace;
  font-size:10px;
  letter-spacing:.09em;
  text-transform:uppercase;
}
.world-history-footer a{transition:color .15s ease,transform .15s ease}
.world-history-footer a:hover{transform:translateX(2px)}

/* Tablet and mobile header: keep essential controls only and prevent overflow. */
@media(max-width:880px){
  body.menu-open{overflow:hidden}
  .sidebar{transition:transform .24s ease;overscroll-behavior:contain}
  .reader{padding-bottom:30px}
  .category-main{padding-bottom:34px}
}

@media(max-width:700px){
  .progress-shell{
    min-height:50px;
    display:grid;
    grid-template-columns:auto auto minmax(0,1fr) auto auto;
    gap:6px;
    padding:6px 8px;
  }
  .progress-shell .topbar-title,
  .progress-shell .progress-label,
  .progress-shell [data-print-page]{display:none!important}
  .progress-shell .section-indicator{
    width:100%;
    min-width:0;
    max-width:none;
    padding:5px 9px;
    font-size:10.5px;
  }
  .progress-shell .section-indicator span{display:block;overflow:hidden;text-overflow:ellipsis}
  .progress-shell .topbtn{width:34px;height:34px;border-radius:10px}

  .reader,.category-reader{width:100%;min-width:0}
  .reader{padding:20px 12px 28px}
  .category-main{padding:22px 12px 30px}
  .page-breadcrumb{margin:0 2px 12px;font-size:11px}

  .hero,.category-hero{
    margin-bottom:18px;
    padding:22px 16px;
    border:1px solid var(--line);
    border-radius:18px;
    background:linear-gradient(145deg,color-mix(in srgb,var(--accent-soft) 52%,var(--card)),var(--card));
    box-shadow:var(--shadow);
  }
  .hero h1,.category-hero h1{
    margin-top:7px;
    padding-bottom:11px;
    overflow-wrap:anywhere;
    font-size:clamp(27px,8.5vw,35px);
  }
  .hero p,.category-hero p{font-size:15.5px;line-height:1.72}
  .hero-meta,.category-stats{gap:7px;margin-top:15px}
  .hero-meta span,.category-stats span{font-size:10.5px;padding:5px 8px}

  .card{margin:13px 0;padding:18px 15px;border-radius:16px}
  .card h2{display:grid;grid-template-columns:auto minmax(0,1fr) auto;align-items:start;font-size:20px;line-height:1.42}
  .card h2 .actions{margin-left:0}
  .card h3{font-size:17.5px}
  .card > p,.card li{font-size:15.5px;line-height:1.72}
  .card ul{margin-left:.8rem;padding-left:0}
  .complete-row{gap:8px;padding-top:14px}
  .complete-btn{width:100%;border-radius:12px;text-align:center}
  .section-meta{align-self:flex-end;margin-top:0}

  .category-grid{gap:12px;margin:16px 0 22px}
  .category-card{
    grid-template-columns:42px minmax(0,1fr);
    min-height:0;
    gap:12px;
    padding:15px;
    border-radius:16px;
  }
  .category-card h2{font-size:19px;line-height:1.35}
  .category-card p{font-size:13.5px;line-height:1.62}
  .card-icon{width:42px;height:42px;border-radius:12px;font-size:18px}
  #categorySearch{padding:13px 14px;border-radius:14px}
  .roadmap-box,.seo-content-block{margin:18px 0;padding:17px;border-radius:16px}
  .roadmap-box h2,.seo-content-block h2{font-size:20px}
  .seo-content-block p{font-size:14.5px;line-height:1.72}

  .chapter-meta-bar{border-radius:14px}
  .chapter-nav-card{border-radius:14px}

  .world-history-footer .unified-site-footer-inner{
    padding:25px 16px 18px;
    gap:22px 16px;
  }
  .world-history-footer .unified-site-footer-brand p{font-size:12.5px}
}

@media(max-width:480px){
  .progress-shell{grid-template-columns:auto auto minmax(0,1fr) auto auto}
  .progress-shell .section-indicator i{display:none}
  .progress-shell .section-indicator{padding-inline:8px}

  .page-breadcrumb{display:none}
  .reader{padding-top:14px}
  .category-main{padding-top:16px}

  .card h2{grid-template-columns:auto minmax(0,1fr);column-gap:8px}
  .card h2 .actions{grid-column:2;justify-self:end;margin-top:-2px}
  .idx{width:32px;height:32px;border-radius:9px;font-size:12px}

  .category-card{grid-template-columns:1fr}
  .category-card .card-icon{margin-bottom:2px}
  .category-stats{display:grid;grid-template-columns:1fr 1fr}
  .category-stats span{justify-content:center;text-align:center}

  .chapter-meta-bar{grid-template-columns:1fr!important}
  .chapter-navigation{grid-template-columns:1fr}

  .world-history-footer .unified-site-footer-inner{grid-template-columns:1fr}
  .world-history-footer .unified-site-footer-brand,
  .world-history-footer .unified-site-footer-copy{grid-column:1}
  .world-history-footer nav{
    display:grid;
    grid-template-columns:repeat(2,minmax(0,1fr));
    gap:5px 12px;
  }
  .world-history-footer a{width:auto;padding:6px 0;line-height:1.35}
  .world-history-footer .unified-site-footer-copy{padding-top:14px}
}

@media(max-width:360px){
  .progress-shell{grid-template-columns:auto auto minmax(0,1fr) auto}
  .progress-shell [data-wh-theme-control]{display:none!important}
  .category-stats{grid-template-columns:1fr}
  .world-history-footer nav{grid-template-columns:1fr}
}