/* ===========================================================================
   study.css — shared styling for the static AKTU study-material pages
   (Notes / PYQs / Quantum / Syllabus). Plain static HTML, no PHP.
   Palette: Navy #0a1f44 / Blue #14478f / White. Full-width business look.
   =========================================================================== */

:root{
  /* same palette as /assets/theme.css */
  --navy:#0B1F3A; --blue:#1D4ED8; --blue-d:#1E40AF;
  --ink:#111827; --muted:#6B7280; --line:#E5E7EB; --bg:#F7F8FA;
}
/* Page chrome (top bar, navbar, footer, back button) comes from the site's
   header.php / footer.php — this file only styles the study content. */
html{scroll-behavior:smooth;}
body{background:var(--bg);}
.st-page{color:var(--ink);}
:where(.st-page) a{color:var(--blue);}
.st-page a{text-decoration:none;}


/* ===================== BREADCRUMB + HERO ===================== */
.st-crumb{background:#fff;border-bottom:1px solid var(--line);
  padding:12px clamp(14px,4vw,60px);font-size:13px;color:var(--muted);
  display:flex;flex-wrap:wrap;gap:6px;align-items:center;}
.st-crumb a{font-weight:600;}
.st-crumb .sep{color:#a3adbf;}
.st-hero{background:linear-gradient(135deg,#14478f,#0a2a5c);color:#fff;
  padding:42px clamp(14px,4vw,60px);}
.st-hero h1{font-size:clamp(24px,3.4vw,34px);font-weight:850;margin:0 0 8px;}
.st-hero p{font-size:16px;opacity:.93;max-width:900px;line-height:1.6;margin:0;}

/* ===================== CARD GRID (hubs / lists) ===================== */
.st-body{padding:6px clamp(14px,4vw,60px) 60px;}
.st-section{font-size:22px;color:var(--navy);font-weight:800;margin:28px 0 16px;
  display:flex;align-items:center;gap:10px;}
.st-section::before{content:"";width:6px;height:24px;background:var(--blue);border-radius:4px;}
.st-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px;}
.st-card{display:block;background:#fff;border:1px solid var(--line);border-radius:12px;
  padding:18px 20px;transition:.18s;color:var(--ink);}
.st-card:hover{transform:translateY(-2px);box-shadow:0 12px 30px rgba(8,36,92,.12);border-color:#cdd8f5;}
.st-card .tag{display:inline-block;background:#eef3ff;color:var(--blue);font-weight:700;
  font-size:12px;padding:3px 10px;border-radius:20px;margin-bottom:10px;}
.st-card h3{font-size:17px;color:var(--navy);margin:0 0 6px;font-weight:750;line-height:1.35;}
.st-card p{font-size:13px;color:var(--muted);margin:0;}
.st-card.soon{opacity:.6;cursor:not-allowed;pointer-events:none;}
.st-card.soon .badge{float:right;background:#fff3cd;color:#9a6b00;font-size:11px;
  font-weight:700;padding:2px 8px;border-radius:12px;}

/* ===================== SUBJECT PAGE (W3Schools layout) ===================== */
.st-doc{display:flex;align-items:flex-start;gap:0;max-width:100%;}
.st-side{flex:0 0 270px;background:#fff;border-right:1px solid var(--line);
  align-self:stretch;padding:18px 0;position:sticky;top:104px;max-height:calc(100vh - 104px);overflow-y:auto;}
.st-side h4{font-size:13px;text-transform:uppercase;letter-spacing:.4px;color:var(--muted);
  padding:0 20px 10px;}
.st-side a{display:block;padding:11px 20px;color:#1f2d4d;font-size:14px;font-weight:650;
  border-left:3px solid transparent;}
.st-side a:hover{background:#f1f5ff;color:var(--blue);}
.st-side a.active{background:#eaf1ff;color:var(--blue);border-left-color:var(--blue);font-weight:800;}
.st-content{flex:1 1 auto;min-width:0;padding:26px clamp(16px,3vw,46px) 60px;}
.st-content h1,.st-content .st-h1{font-size:clamp(22px,3vw,30px);color:var(--navy);font-weight:850;margin:0 0 6px;}
.st-content .lead{color:var(--muted);font-size:15px;margin:0 0 22px;}
.st-unit{background:#fff;border:1px solid var(--line);border-radius:12px;padding:20px 22px;
  margin:0 0 18px;box-shadow:0 6px 18px rgba(15,23,42,.05);scroll-margin-top:120px;}
.st-unit h2{font-size:19px;color:var(--navy);font-weight:800;margin:0 0 10px;}
.st-unit p{color:#3a4761;line-height:1.65;font-size:15px;margin:0 0 10px;}
.st-pdf{width:100%;height:520px;border:1px solid var(--line);border-radius:10px;margin:14px 0;background:#fff;}
.dl-btn{display:inline-flex;align-items:center;gap:8px;background:var(--blue);color:#fff;
  padding:11px 18px;border-radius:8px;font-size:14px;font-weight:800;}
.dl-btn:hover{background:var(--blue-d);color:#fff;}
.st-prevnext{display:flex;justify-content:space-between;gap:12px;margin-top:24px;flex-wrap:wrap;}
.st-prevnext a{background:#fff;border:1px solid var(--line);border-radius:10px;padding:12px 18px;
  font-weight:750;color:var(--navy);}
.st-prevnext a:hover{border-color:#cdd8f5;color:var(--blue);}
@media(max-width:880px){
  .st-doc{flex-direction:column;}
  .st-side{flex-basis:auto;width:100%;position:static;max-height:none;border-right:0;
    border-bottom:1px solid var(--line);}
  .st-side a{display:inline-block;border-left:0;border-bottom:3px solid transparent;}
}

/* ===================== FOOTER ===================== */
@media(max-width:576px){.st-grid{grid-template-columns:1fr;}.st-hero h1{font-size:24px;}}

/* ===================== FLOATING BACK BUTTON ===================== */
@media(max-width:576px){}

/* ---- cross-links ("Also for this subject") ---- */
.st-related{margin:30px 0 0;padding-top:18px;border-top:1px solid #e8edf7;}
.st-related h3{font-size:16px;color:#0a1f44;margin:0 0 12px;}
.st-related a{display:inline-block;background:#eef3ff;color:#14478f;text-decoration:none;font-weight:600;
  font-size:14px;padding:8px 14px;border-radius:20px;margin:0 8px 8px 0;}
.st-related a:hover{background:#14478f;color:#fff;}
.st-side a.back{color:#14478f;font-weight:700;border-bottom:1px solid #e7ebf6;border-radius:0;margin-bottom:10px;}

/* ---- MBA topic notes (article body) ---- */
.note-article h2{font-size:23px;color:#0a1f44;margin:32px 0 12px;font-weight:800;border-left:5px solid #14478f;padding-left:12px;}
.note-article h3{font-size:19px;color:#1a3a7a;margin:22px 0 10px;}
.note-article h4{font-size:16px;color:#2a2a55;margin:18px 0 8px;}
.note-article p,.note-article li{font-size:16.5px;line-height:1.85;color:#2f3742;}
.note-article ul,.note-article ol{padding-left:24px;margin:0 0 16px;}
.note-article .note-def{background:#eef3ff;border:1px solid #d6e0ff;border-left:5px solid #14478f;border-radius:8px;padding:15px 18px;margin:0 0 17px;}
.note-article .note-tip{background:#fff7e6;border:1px solid #ffe1a6;border-left:5px solid #f0a500;border-radius:8px;padding:15px 18px;margin:0 0 17px;}
.note-article .note-key{background:#e9fbf0;border:1px solid #b9ecca;border-left:5px solid #16a34a;border-radius:8px;padding:15px 18px;margin:0 0 17px;}
.note-article table{width:100%;border-collapse:collapse;margin:0 0 18px;font-size:15px;display:block;overflow-x:auto;}
.note-article th,.note-article td{border:1px solid #dde3ee;padding:10px 12px;text-align:left;vertical-align:top;}
.note-article th{background:#f0f4ff;color:#08245c;}
.st-prevnext small{display:block;font-size:12px;color:#889;font-weight:600;margin-bottom:3px;}
.note-article h2.st-h1{border-left:0;padding-left:0;margin:0 0 6px;font-size:clamp(22px,3vw,30px);}