.subject-link { display: block; transition: transform .2s, box-shadow .2s, border-color .2s; }
.subject-link:hover { transform: translateY(-6px); border-color: var(--red); box-shadow: 0 20px 45px rgba(11,23,45,.13); }
.subject-link b { display: inline-block; margin-top: 18px; color: var(--red); font-size: 12px; letter-spacing: .04em; }
.topic-page { padding: 85px 0 115px; }
.topic-index { display: grid; grid-template-columns: repeat(3,1fr); gap: 15px; margin-bottom: 85px; }
.topic-index a { min-height: 115px; padding: 22px; background: #fff; border: 1px solid #ddd9d1; display: flex; flex-direction: column; justify-content: space-between; transition: transform .2s,border-color .2s; }
.topic-index a:hover { transform: translateY(-4px); border-color: var(--red); }
.topic-index small { color: var(--red); font-weight: 800; letter-spacing: .12em; }
.topic-index strong { font: 22px Georgia,"Times New Roman",serif; font-weight: 400; }
.topic-section { scroll-margin-top: 25px; display: grid; grid-template-columns: .58fr 1.42fr; gap: 55px; padding: 55px 0; border-top: 1px solid #d8d4cc; }
.topic-section h2 { font-size: 36px; line-height: 1.05; font-weight: 400; margin: 0; }
.topic-content { display: grid; gap: 16px; }
.topic-content p { margin: 0; color: var(--muted); line-height: 1.75; }
.formula-box { padding: 21px 24px; background: var(--navy); color: #fff; border-left: 4px solid var(--red); font: 20px Georgia,"Times New Roman",serif; line-height: 1.8; overflow-x: auto; }
.formula-box span { color: #ff7780; }
.note-box { padding: 18px 22px; background: #e9e5dc; color: #50596a; line-height: 1.65; }
.back-top { display: inline-block; margin-top: 10px; color: var(--red); font-size: 12px; font-weight: 800; }
@media(max-width:850px){.topic-index{grid-template-columns:1fr 1fr}.topic-section{grid-template-columns:1fr;gap:22px}}
@media(max-width:520px){.topic-index{grid-template-columns:1fr}.topic-page{padding-top:60px}.topic-section h2{font-size:31px}}
.empty-subject-page {
  min-height: 58vh;
}

/* Righe aggiuntive nelle schede materia: Quiz ed Esercizi */
.subject-link .card-extra-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 12px;
  padding: 12px 0 0;
  border-top: 1px solid #e4dfd6;
  color: var(--ink);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .02em;
}
.subject-link .card-extra-row + .card-extra-row { margin-top: 10px; }
.subject-link .card-extra-row i {
  color: var(--red);
  font-style: normal;
  font-size: 15px;
}
.subject-link:hover .card-extra-row { color: var(--red); }


/* Schede con collegamenti separati: Formule, Quiz, Esercizi */
.subject-card .subject-main{display:block;}
.subject-card h3 a{display:inline;}
.subject-card .card-extra-row{display:flex;}
.subject-card:hover .card-extra-row{color:var(--ink);}
.subject-card .card-extra-row:hover{color:var(--red);}