/* Prednáška 3 – Backpropagation */

/* horný panel labu: prepínače + posuvník */
.l3-top { display: flex; flex-wrap: wrap; align-items: flex-end; gap: 14px 28px; margin-bottom: 18px; }
.l3-group .lab-label { margin-bottom: 8px; }
.l3-grow { flex: 1 1 220px; min-width: 0; max-width: 360px; }
.l3-row + .l3-row, .l3-mt { margin-top: 18px; }
.l3-nomb { margin-bottom: 0 !important; }
.l3-teal { color: var(--teal) !important; }
#lab-steps .l3-row { grid-template-columns: minmax(0, 1fr) minmax(0, 1.08fr); }

/* sieť 2-2-1 */
.l3-net { width: 100%; height: auto; }
.l3-edge { transition: stroke-width .25s, opacity .25s; }
.l3-edge.l3-off { opacity: .28; }
.l3-edge.l3-on { filter: drop-shadow(0 0 4px rgba(255, 189, 99, .55)); }
.l3-node { stroke: rgba(255, 255, 255, .35); stroke-width: 1.5; transition: fill .3s, stroke .2s; }
.l3-node.l3-on { stroke: var(--accent); stroke-width: 3; }
.stage svg text.l3-nn { font-size: 12px; font-weight: 600; }
.stage svg text.l3-nv { font-size: 12px; font-weight: 600; }
.l3-pill rect { fill: #0e121a; stroke: rgba(255, 255, 255, .16); stroke-width: 1; transition: stroke .2s; }
.stage svg .l3-pill text { font-size: 12px; fill: var(--text); }
.stage svg .l3-pill text.l3-p2 { fill: var(--accent-hi); }
.l3-pill { transition: opacity .25s; }
.l3-pill.l3-off { opacity: .35; }
.l3-pill.l3-on rect { stroke: var(--accent); stroke-width: 1.6; }
.l3-pill.l3-sel rect { stroke: var(--teal); stroke-width: 2; fill: #0f1d22; }
.l3-click { cursor: pointer; }
.l3-click:hover rect { stroke: rgba(255, 255, 255, .5); }
.l3-pill.l3-t rect { fill: rgba(90, 217, 154, .12); stroke: rgba(90, 217, 154, .5); }
.stage svg .l3-pill.l3-t text { fill: var(--green); }
.l3-pill.l3-d rect { fill: rgba(255, 122, 122, .1); stroke: rgba(255, 122, 122, .45); }
.stage svg .l3-pill.l3-d text { fill: #ffb0b0; }
.l3-pill.l3-d.l3-on rect, .l3-pill.l3-t.l3-on rect { stroke: var(--accent); }

/* krokovanie */
.l3-kick { font: 600 .75rem/1 var(--font); letter-spacing: .08em; text-transform: uppercase; color: var(--text-3); }
.l3-dots { display: flex; gap: 5px; margin-top: 10px; }
.l3-dots i { flex: 1; height: 4px; border-radius: 4px; background: var(--surface-3); transition: background-color .25s; }
.l3-dots i.done { background: rgba(242, 165, 65, .45); }
.l3-dots i.on { background: var(--accent); }
.prose .l3-step-t { margin-top: 14px !important; font-size: 1.1875rem; }
.l3-step-d { margin-top: 6px; color: var(--text-2); font-size: .9375rem; line-height: 1.6; }
.l3-read { font-size: .8125rem; line-height: 1.85; white-space: pre; }

/* hlásenia */
.l3-msg { padding: 10px 14px; border-radius: var(--r-sm); border: 1px solid var(--line); background: rgba(255, 255, 255, .02); color: var(--text-2); font-size: .9063rem; line-height: 1.5; }
.l3-msg.ok { border-color: rgba(90, 217, 154, .4); background: rgba(90, 217, 154, .07); color: var(--text); }
.l3-msg.bad { border-color: rgba(255, 122, 122, .4); background: rgba(255, 122, 122, .07); color: var(--text); }

/* výstupy vs. ciele */
.l3-outs { display: grid; grid-template-columns: 3.4em 3.2em minmax(0, 1fr) 3.6em; gap: 6px 10px; align-items: center; font-size: .875rem; color: var(--text-2); }
.l3-outs-h { font-size: .75rem; color: var(--text-3); margin-bottom: 6px; }
.l3-outs > b { font: 600 .875rem/1 var(--font-mono); color: var(--text); text-align: right; }
.l3-tg { color: var(--green); }
.l3-bar { position: relative; height: 10px; border-radius: 6px; background: var(--surface-3); overflow: hidden; }
.l3-bar i { position: absolute; inset: 0 auto 0 0; border-radius: 6px; transition: width .2s; }
.l3-bar::after { content: ""; position: absolute; left: 50%; top: -2px; bottom: -2px; width: 1px; background: rgba(255, 255, 255, .3); }

.l3-tbl td, .l3-tbl th { padding: 8px 14px; }
.l3-clicky { cursor: crosshair; }

/* MNIST: stĺpce */
.l3-row-m { grid-template-columns: minmax(0, .7fr) minmax(0, 1.3fr); }
.l3-digit { max-width: 260px; width: 100%; }
.l3-bars { display: grid; gap: 4px; }
.l3-bars-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 4px 28px; }
.l3-brow { display: grid; grid-template-columns: 2.4em minmax(0, .8fr) 3em minmax(0, 1.2fr) 4.4em; gap: 8px; align-items: center; padding: 2px 6px; border-radius: 6px; font-size: .8125rem; color: var(--text-2); }
.l3-brow.hl { background: rgba(90, 217, 154, .09); color: var(--text); }
.l3-brow.hl .l3-bl { color: var(--green); font-weight: 700; }
.l3-bn { text-align: right; color: var(--text); font-size: .8125rem; }
.l3-bact, .l3-bwish { position: relative; height: 10px; border-radius: 4px; background: var(--surface-3); overflow: hidden; }
.l3-bact i { position: absolute; inset: 0 auto 0 0; background: #cfd3db; border-radius: 4px; }
.l3-bwish i { position: absolute; top: 0; bottom: 0; border-radius: 3px; }
.l3-bwish::after { content: ""; position: absolute; left: 50%; top: 0; bottom: 0; width: 1px; background: rgba(255, 255, 255, .35); }

/* schéma v texte */
.l3-eqmap { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.l3-eq { padding: 16px 18px; border-radius: var(--r-sm); border: 1px solid var(--line); background: var(--surface); }
.l3-eq b { display: block; font: 600 .75rem/1 var(--font); letter-spacing: .08em; text-transform: uppercase; color: var(--accent-hi); margin-bottom: 10px; }
.l3-eq .f { font-family: var(--font-mono); font-size: .9375rem; color: var(--text); overflow-x: auto; white-space: nowrap; padding-bottom: 2px; }
.l3-eq p { margin-top: 8px; font-size: .9063rem !important; line-height: 1.55 !important; color: var(--text-2) !important; }
.l3-eq sub, .l3-eq sup { font-size: .7em; }

@media (max-width: 1020px) {
  #lab-steps .l3-row { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 760px) {
  .l3-row-m, .l3-eqmap { grid-template-columns: minmax(0, 1fr); }
  .l3-digit { max-width: 200px; }
  .l3-bars-2 { grid-template-columns: minmax(0, 1fr); }
  .l3-top { gap: 12px 20px; }
  .l3-grow { max-width: none; }
  .l3-brow { grid-template-columns: 2.4em minmax(0, .7fr) 2.8em minmax(0, 1.3fr) 4.2em; gap: 6px; padding: 2px 4px; }
}