/* Demo de descenso por gradiente paso a paso (js/components/demos/gradient-descent.js) */
.gdd { display: grid; gap: 1.4rem; }
.gdd-top { display: grid; grid-template-columns: minmax(0, 1.65fr) minmax(0, 1fr); gap: 1.6rem; align-items: stretch; }
.gdd-stage { position: relative; margin: 0; border-radius: var(--r); background: linear-gradient(180deg, #0b0b10, #07070a); overflow: hidden; }
.gdd-stage canvas { display: block; width: 100%; height: auto; aspect-ratio: 16 / 10; touch-action: manipulation; }
.gdd-hud { position: absolute; right: 1rem; top: 0.7rem; display: flex; gap: 1.1rem; font: 500 0.72rem var(--mono); color: var(--muted2); pointer-events: none; }
.gdd-hud b { color: var(--text); font-weight: 500; font-variant-numeric: tabular-nums; display: inline-block; min-width: 4.4ch; }
.gdd-side { display: flex; flex-direction: column; gap: 0.9rem; min-width: 0; }
.gdd-h { font: 500 0.7rem var(--mono); letter-spacing: 0.1em; text-transform: uppercase; color: var(--accent); }
.gdd-steps { list-style: none; padding: 0; margin: 0; display: grid; gap: 0.55rem; }
.gdd-steps li { display: grid; gap: 0.25rem; padding: 0.75rem 0.9rem; border-radius: 10px; background: var(--card); opacity: 0.55; transition: opacity 0.2s, background 0.2s, box-shadow 0.2s; }
.gdd-steps li.done { opacity: 0.8; }
.gdd-steps li.on { opacity: 1; background: var(--card2); box-shadow: inset 2px 0 0 var(--accent); }
.gdd-steps li:nth-child(2).on { box-shadow: inset 2px 0 0 #fbbf24; }
.gdd-steps b { font: 500 0.68rem var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); }
.gdd-steps code { font: 400 0.8rem/1.5 var(--mono); color: var(--text); overflow-wrap: anywhere; background: none; padding: 0; }
.gdd-verdict { font-size: 0.86rem; line-height: 1.55; color: var(--muted); padding: 0.1rem 0 0; min-height: 4.6em; }
.gdd-verdict[data-kind="converged"] { color: #86efac; } .gdd-verdict[data-kind="diverged"] { color: #fca5a5; } .gdd-verdict[data-kind="oscillating"], .gdd-verdict[data-kind="slow"] { color: #fcd34d; }
.gdd-controls { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); align-items: end; gap: 1rem 1.6rem; }
.gdd-controls .gdd-btns { grid-column: 1 / -1; }
.gdd-btns { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.gdd-btns .btn { min-width: 6.6rem; justify-content: center; } .gdd-btns .btn:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }
.gdd-field { display: grid; gap: 0.3rem; font-size: 0.78rem; color: var(--muted); min-width: 0; }
.gdd-field b { font: 500 0.78rem var(--mono); color: var(--text); margin-left: 0.4rem; }
.gdd-field select { background: var(--bg2); color: var(--text); border: 1px solid var(--border2); border-radius: 6px; padding: 0.4rem 0.5rem; font: inherit; }
.gdd-field input[type="range"] { -webkit-appearance: none; appearance: none; height: 20px; background: transparent; width: 100%; cursor: pointer; }
.gdd-field input[type="range"]::-webkit-slider-runnable-track { height: 4px; border-radius: 2px; background: #2a2a34; }
.gdd-field input[type="range"]::-moz-range-track { height: 4px; border-radius: 2px; background: #2a2a34; }
.gdd-field input[type="range"]::-webkit-slider-thumb { -webkit-appearance: none; width: 16px; height: 16px; border-radius: 50%; background: var(--accent); margin-top: -6px; border: 0; box-shadow: 0 0 0 4px rgba(var(--accent-r), 0.16); }
.gdd-field input[type="range"]::-moz-range-thumb { width: 16px; height: 16px; border-radius: 50%; background: var(--accent); border: 0; }
.gdd-presets { display: flex; flex-wrap: wrap; gap: 0.45rem; }
.gdd-chip { font: 500 0.72rem var(--mono); color: var(--muted); background: transparent; border: 1px solid var(--border2); border-radius: 999px; padding: 0.3rem 0.75rem; transition: color 0.2s, border-color 0.2s; }
.gdd-chip:hover { color: var(--accent); border-color: var(--accent); }
.gdd-loss { margin: 0; } .gdd-loss figcaption { font: 500 0.7rem var(--mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted2); margin-bottom: 0.4rem; } .gdd-loss small { text-transform: none; letter-spacing: 0; color: var(--muted); font-size: 0.72rem; }
.gdd-loss svg { display: block; width: 100%; height: 110px; background: var(--bg2); border-radius: 10px; }
.gdd-credit { font-size: 0.74rem; color: var(--muted2); line-height: 1.55; max-width: none; margin: 0; }
.gdd-credit a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; } .gdd-credit code { font-size: 0.72rem; }
@media (max-width: 860px) { .gdd-top { grid-template-columns: minmax(0, 1fr); } .gdd-hud { right: 0.6rem; gap: 0.7rem; font-size: 0.66rem; } .gdd-verdict { min-height: 0; } }
@media (max-width: 520px) { .gdd-stage canvas { aspect-ratio: 4 / 3.4; } }