/* --- Calcul littéral & équations (4e, 3e, 2de) : balance des équations, identités remarquables --- */
:root {
  --clbal-metal: #475569;
  --clbal-x: #7c3aed;
  --clbal-unit: #f59e0b;
}

[data-bs-theme="dark"] {
  --clbal-metal: #94a3b8;
  --clbal-x: #a78bfa;
  --clbal-unit: #fbbf24;
}

/* Balance : fléau horizontal, plateaux, tuiles « x » et poids « 1 » */
.clbal-scene { margin-bottom: 0.75rem; }

.clbal-svg {
  display: block;
  width: 100%;
  max-width: 420px;
  margin: 0 auto;
}

.clbal-stand { fill: var(--clbal-metal); opacity: 0.35; }
.clbal-beam { stroke: var(--clbal-metal); stroke-width: 6; stroke-linecap: round; }
.clbal-pivot { fill: var(--clbal-metal); }
.clbal-string { stroke: var(--clbal-metal); stroke-width: 1.5; opacity: 0.6; }
.clbal-pan { fill: var(--mm-teal-soft); stroke: var(--mm-teal); stroke-width: 2; }
.clbal-tile-x { fill: var(--clbal-x); }
.clbal-tile-1 { fill: var(--clbal-unit); }

.clbal-svg text {
  fill: #fff;
  font-size: 12px;
  font-weight: 700;
  text-anchor: middle;
}

.clbal-members {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  max-width: 420px;
  margin: 0.25rem auto 0;
  font-size: 1.15em;
  text-align: center;
}

.clbal-equal { font-weight: 700; }

/* Commandes : opération, opérande, appliquer, annuler */
.clbal-controls {
  display: grid;
  gap: 0.6rem;
}

.clbal-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.clbal-ops {
  display: inline-flex;
  gap: 0.25rem;
}

.clbal-op {
  width: 2.5rem;
  height: 2.5rem;
  border: 2px solid var(--school-border);
  border-radius: var(--school-radius-md);
  background: var(--school-surface);
  color: var(--school-text);
  font-size: 1.2rem;
  font-weight: 700;
}

.clbal-op.is-active {
  border-color: var(--mm-teal);
  background: var(--mm-teal-soft);
  color: var(--mm-teal);
}

.clbal-operand {
  width: 8rem;
  flex: 0 0 auto;
}

.clbal-history .cf-steps { margin-top: 0.5rem; }

/* Identités remarquables : encadré des trois formules */
.cl-identities {
  padding: 0.5rem 0.8rem;
  margin-bottom: 0.75rem;
  border: 2px solid var(--mm-teal);
  border-radius: var(--school-radius-md);
  text-align: center;
}

.cl-identities p { margin: 0.2rem 0; }