:root{
  --bg:#0b0b0c;
  --panel:#0f1720;
  --muted:#9aa4b2;
  --accent:#1e90ff;
  --card:#0f1724;
  --glass:rgba(255,255,255,0.03);
}
body .studyhub-subjects, body .studyhub-chapters, body .studyhub-resources{display:flex;flex-wrap:wrap;gap:1rem;margin:1rem 0}
.sh-card{background:linear-gradient(180deg,var(--panel),var(--card));color:#fff;border-radius:10px;display:block;overflow:hidden;text-decoration:none;box-shadow:0 6px 18px rgba(2,6,23,0.6);width:260px;transform:translateY(8px);opacity:0;transition:transform .42s cubic-bezier(.2,.9,.2,1),opacity .42s}
.sh-card.in-view{transform:none;opacity:1}
.sh-card-media{height:120px;background-size:cover;background-position:center}
.sh-card-body{padding:14px}
.sh-card-body h3{margin:0 0 6px;font-size:1.05rem;color:var(--accent)}
.sh-card-body p{margin:0;font-size:.9rem;color:var(--muted)}
.sh-chapter{background:var(--glass);padding:12px;border-radius:8px;color:#fff;min-width:220px;flex:1 1 220px;transition:transform .2s}
.sh-chapter a{color:#fff;text-decoration:none}
.sh-chapter:hover{transform:translateY(-6px)}
.sh-resource{background:linear-gradient(180deg,rgba(255,255,255,0.02),rgba(255,255,255,0.01));padding:12px;border-radius:8px;color:#fff;min-width:280px;flex:1 1 280px}
.sh-resource h4{margin:0 0 8px}
.sh-btn{display:inline-block;padding:8px 12px;border-radius:6px;background:var(--accent);color:#00121a;text-decoration:none;font-weight:600}

/* Simple responsive */
@media(max-width:720px){
  .sh-card{width:100%}
  .studyhub-subjects, .studyhub-chapters, .studyhub-resources{flex-direction:column}
}

/* Light mode support when body has .studyhub-light */
body.studyhub-light{--bg:#ffffff;--panel:#f5f7fb;--muted:#55606a;--accent:#0b63d6;--card:#ffffff;--glass:rgba(2,6,23,0.03);color:#111}

/* Page background hook (theme may override) */
body .studyhub-root{background:var(--bg);padding:18px;color:var(--muted)}