/* Estilos específicos da demo de backpropagation: blocos de matrizes da
   seção vetorizada, com colchetes desenhados via bordas. */

.matrix-board {
  display: flex;
  flex-direction: column;
  gap: .2rem;
  margin: .4rem 0 .9rem;
}

.matrix-group {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: .35rem .8rem;
  margin-bottom: .35rem;
}

.matrix-group-title {
  flex-basis: 100%;
  color: var(--comment);
  font-size: .72rem;
  text-transform: uppercase;
  letter-spacing: .07em;
  margin: .15rem 0 0;
}

.matrix-block {
  border: 1.5px solid transparent;
  border-radius: 8px;
  padding: .3rem .5rem .4rem;
  transition: opacity .2s, border-color .2s, box-shadow .2s;
}
.matrix-block.pending { opacity: .32; }
.matrix-block.active-in { border-color: var(--purple); }
.matrix-block.active-out {
  border-color: var(--purple);
  box-shadow: 0 0 0 1.5px var(--purple), 0 0 14px -4px var(--purple);
}

.matrix-label {
  display: flex;
  align-items: baseline;
  gap: .45rem;
  font-size: .85rem;
  margin-bottom: .2rem;
}
.matrix-dims { color: var(--comment); font-size: .72rem; }

.matrix {
  position: relative;
  display: inline-grid;
  gap: .12rem .7rem;
  padding: .28rem .55rem;
  font-family: "STIX Two Math", "Cambria Math", Georgia, serif;
  font-size: .88rem;
}
.matrix::before,
.matrix::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  width: 7px;
  border: 1.5px solid var(--comment);
}
.matrix::before { left: 0; border-right: none; }
.matrix::after { right: 0; border-left: none; }

.matrix span {
  text-align: right;
  font-variant-numeric: tabular-nums;
}
.matrix-block[data-kind="given"] .matrix span { color: var(--cyan); }
.matrix-block[data-kind="fwd"] .matrix span { color: var(--green); }
.matrix-block[data-kind="bwd"] .matrix span { color: var(--pink); }
.matrix-block.pending .matrix span { color: var(--comment); }

/* ── Seções 4 e 5 (MLP Playground importado): grade de mapas dos neurônios escondidos ── */

.neuron-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: .8rem;
}

.neuron-box {
  display: flex;
  flex-direction: column;
}

.neuron-box canvas {
  width: 100%;
  aspect-ratio: 1 / 1;
  height: auto;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 6px;
}

@media (max-width: 700px) {
  .neuron-grid { grid-template-columns: repeat(2, 1fr); }
}