/* Study hub pages: By Subject / By Stream / Chapter-wise */
.sh-wrap{position:relative;z-index:1;max-width:1040px;margin:0 auto;padding:30px 24px 80px}
.sh-hero{text-align:center;max-width:680px;margin:0 auto 22px}
.sh-eyebrow{display:inline-flex;align-items:center;gap:6px;font-size:12px;font-weight:800;letter-spacing:.06em;text-transform:uppercase;color:var(--blue);background:#EFF4FF;border:1px solid #D6E3FF;padding:5px 12px;border-radius:999px}
.sh-hero h1{font-size:clamp(26px,4.4vw,38px);line-height:1.15;font-weight:800;color:var(--ink);margin:14px 0 10px;letter-spacing:-.02em}
.sh-hero p{color:var(--muted);font-size:15.5px;line-height:1.6;margin:0}
/* tab bar (a div, not <nav>: the site-wide nav{} rule would squash it) */
.sh-tabs{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:0 auto 26px;max-width:880px;height:auto;padding:0}
.sh-tab{display:flex;align-items:center;gap:10px;padding:11px 14px;background:rgba(255,255,255,.9);border:1.5px solid var(--border);border-radius:14px;text-decoration:none;transition:.2s}
.sh-tab i{font-size:20px;color:var(--blue);flex:none}
.sh-tab b{display:block;font-size:13.5px;color:var(--ink);line-height:1.2}.sh-tab small{display:block;font-size:11px;color:var(--muted)}
.sh-tab:hover{border-color:#93B4FF;transform:translateY(-2px);box-shadow:0 10px 22px rgba(37,99,235,.12)}
.sh-tab.on{background:linear-gradient(135deg,#2563EB,#4F46E5);border-color:transparent;box-shadow:0 10px 22px rgba(37,99,235,.28)}
.sh-tab.on i,.sh-tab.on b{color:#fff}.sh-tab.on small{color:#DCE6FF}
.sh-search{display:flex;align-items:center;gap:10px;max-width:640px;margin:0 auto 26px;background:#fff;border:1.5px solid var(--border);border-radius:16px;padding:6px 6px 6px 16px;box-shadow:0 8px 24px rgba(15,23,42,.06)}
.sh-search:focus-within{border-color:var(--blue);box-shadow:0 0 0 3px rgba(37,99,235,.15)}
.sh-search i{color:var(--muted);font-size:20px}.sh-search input{flex:1;min-width:0;border:0;outline:0;background:transparent;font-size:15px;padding:10px 2px;color:var(--ink)}
.sh-search button{border:0;background:var(--blue);color:#fff;font-weight:700;font-size:14px;padding:10px 20px;border-radius:12px;cursor:pointer}
/* subject cards */
.sh-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.sh-card{background:#fff;border:1px solid var(--border);border-radius:18px;padding:18px;transition:.2s;position:relative;overflow:hidden}
.sh-card::before{content:"";position:absolute;left:0;right:0;top:0;height:4px;background:var(--c)}
.sh-card:hover{transform:translateY(-3px);box-shadow:0 14px 30px rgba(15,23,42,.10);border-color:var(--c)}
.sh-card-top{display:flex;align-items:center;gap:12px;margin-bottom:14px}
.sh-card h2{font-size:17px;font-weight:800;color:var(--ink);margin:0;line-height:1.2}.sh-card small{color:var(--muted);font-size:12px}
.sh-ico{width:46px;height:46px;border-radius:14px;background:var(--bg,#EFF4FF);color:var(--c,var(--blue));display:flex;align-items:center;justify-content:center;font-size:23px;flex:none}
.sh-ico.big{width:56px;height:56px;font-size:28px;background:rgba(255,255,255,.2);color:#fff}
.sh-pills{display:flex;flex-wrap:wrap;gap:8px}
.sh-pills a{display:inline-flex;align-items:center;gap:6px;font-size:12.5px;font-weight:700;color:var(--ink);background:#F3F6FC;border:1px solid var(--border);padding:6px 12px;border-radius:999px;text-decoration:none;transition:.15s}
.sh-pills a:hover{background:var(--c,var(--blue));border-color:var(--c,var(--blue));color:#fff}
.sh-pills em{font-style:normal;font-size:10px;font-weight:800;background:#FEE2E2;color:#B91C1C;padding:1px 6px;border-radius:99px}
.sh-pills.big a{font-size:14px;padding:9px 16px;background:#fff}
.sh-pills.big a.on{background:var(--c,var(--blue));border-color:var(--c,var(--blue));color:#fff;box-shadow:0 8px 18px rgba(37,99,235,.22)}
.sh-pills.big a.on em{background:rgba(255,255,255,.25);color:#fff}
.sh-pills.big a.dim{opacity:.55}.sh-pills.big a em{background:#EAF0FF;color:var(--blue)}
/* streams */
.sh-streams{display:grid;gap:18px}
.sh-stream{background:#fff;border:1px solid var(--border);border-radius:20px;overflow:hidden;box-shadow:0 8px 24px rgba(15,23,42,.05)}
.sh-stream-head{display:flex;align-items:center;gap:16px;padding:20px 22px;color:#fff;background:linear-gradient(135deg,var(--c1),var(--c2))}
.sh-stream-head h2{font-size:21px;font-weight:800;margin:0}.sh-stream-head p{margin:4px 0 0;font-size:13px;opacity:.92;max-width:560px;line-height:1.5}
.sh-chip{margin-left:auto;background:rgba(255,255,255,.2);border:1px solid rgba(255,255,255,.35);font-size:12px;font-weight:800;padding:5px 12px;border-radius:999px;white-space:nowrap}
.sh-stream-body{padding:8px 22px 16px}
.sh-row{display:flex;gap:16px;align-items:flex-start;padding:12px 0;border-bottom:1px dashed var(--border)}.sh-row:last-child{border:0}
.sh-row>b{flex:none;width:84px;font-size:13.5px;color:var(--ink);padding-top:6px}
.sh-stream .sh-pills a:hover{background:var(--c1);border-color:var(--c1)}
.sh-soon{color:var(--muted);font-size:13.5px;margin:14px 0 6px}
.sh-note{margin-top:20px;background:#EFF4FF;border:1px solid #D6E3FF;color:#1E40AF;border-radius:14px;padding:14px 18px;font-size:14px}.sh-note a{font-weight:700;color:var(--blue)}
/* chapter-wise */
.sh-step{display:flex;align-items:center;gap:10px;font-weight:800;color:var(--ink);font-size:15px;margin:22px 0 12px}
.sh-step .n{width:26px;height:26px;border-radius:50%;background:linear-gradient(135deg,#2563EB,#7C3AED);color:#fff;font-size:13px;display:flex;align-items:center;justify-content:center}
.sh-block{margin-top:26px;background:#fff;border:1px solid var(--border);border-radius:20px;padding:6px;box-shadow:0 8px 24px rgba(15,23,42,.05)}
.sh-block-head{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:14px 16px 8px}
.sh-block-head h2{font-size:18px;font-weight:800;color:var(--ink);margin:0}.sh-block-head a{font-size:13px;font-weight:700;color:var(--blue);text-decoration:none}
.sh-chlist{display:grid;grid-template-columns:1fr 1fr;gap:4px;padding:6px}
.sh-ch{display:flex;align-items:center;gap:12px;padding:11px 12px;border-radius:12px;text-decoration:none;transition:.15s;min-width:0}
.sh-ch:hover{background:#F3F6FC}
.sh-ch .num{width:32px;height:32px;border-radius:10px;background:#EFF4FF;color:var(--blue);font-weight:800;font-size:13px;display:flex;align-items:center;justify-content:center;flex:none}
.sh-ch .t{flex:1;min-width:0}.sh-ch .t b{display:block;font-size:14px;color:var(--ink);font-weight:600;line-height:1.35;overflow-wrap:anywhere}.sh-ch .t small{color:var(--muted);font-size:12px}
.sh-ch .free{font-size:10.5px;font-weight:800;text-transform:uppercase;background:#DCFCE7;color:#166534;padding:3px 9px;border-radius:99px;flex:none}
.sh-ch>.ti-chevron-right{color:var(--muted)}
.sh-empty{text-align:center;color:var(--muted);padding:30px 10px;grid-column:1/-1}
@media(max-width:900px){.sh-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.sh-tabs{grid-template-columns:repeat(2,1fr)}}
@media(max-width:640px){.sh-wrap{padding:22px 16px 60px}.sh-grid,.sh-chlist{grid-template-columns:1fr}.sh-stream-head{flex-wrap:wrap}.sh-chip{margin-left:0}.sh-row{flex-direction:column;gap:6px}.sh-row>b{width:auto;padding:0}}