/* Sección 3: Cómo funciona (escena fija con scroll) */
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ember-2);
  font: 500 0.76rem/1 var(--font-mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.kicker::before {
  content: "";
  width: 26px;
  height: 2px;
  border-radius: 2px;
  background: var(--ember);
}

.how { position: relative; padding-bottom: clamp(3rem, 6vw, 5rem); }
.how-intro {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-block: clamp(4.5rem, 9vw, 8rem) clamp(2rem, 4vw, 3.4rem);
  text-align: center;
}
.how-title {
  margin-top: 1.2rem;
  max-width: 17em;
  font: 700 clamp(2rem, 5.2vw, 4rem) / 1.05 var(--font-display);
  letter-spacing: -0.034em;
  text-wrap: balance;
}
.how-lede {
  max-width: 34rem;
  margin-top: 1.2rem;
  color: var(--text-2);
  font-size: clamp(1rem, 1.6vw, 1.15rem);
}

/* Base sin JS: pasos y paneles apilados */
.how-scene { position: relative; }
.how-grid { display: grid; grid-template-columns: minmax(0, 1fr); gap: 2rem; align-items: start; }
.how-ambient, .docs { display: none; }
.step-caption { display: none; }

.steps { display: grid; gap: 0.9rem; margin: 0; padding: 0; list-style: none; }
.step {
  position: relative;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 1rem;
  width: 100%;
  min-height: 44px;
  padding: 1.15rem 1.25rem;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: color-mix(in srgb, var(--bg-2) 60%, transparent);
  color: inherit;
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition: opacity 0.35s, border-color 0.35s, background-color 0.35s;
}
.step-num { padding-top: 0.25rem; color: var(--text-3); font: 500 0.8rem/1 var(--font-mono); }
.step-title { display: block; font: 700 1.2rem/1.2 var(--font-display); letter-spacing: -0.02em; }
.step-desc { display: block; margin-top: 0.45rem; color: var(--text-2); font-size: 0.95rem; line-height: 1.55; }
.step-tags { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-top: 0.8rem; }
.step-tags i {
  padding: 0.28rem 0.6rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text-2);
  font: 500 0.68rem/1.2 var(--font-mono);
  font-style: normal;
  letter-spacing: 0.04em;
}
.step-bar { position: absolute; left: 0; right: 0; bottom: 0; height: 2px; }
.step-bar i {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--ember-2), var(--crimson));
  transform: scaleX(0);
  transform-origin: left;
}
.how-cta { margin-top: 1.4rem; }

.how-stage { position: relative; min-width: 0; }
.window {
  position: relative;
  z-index: 2;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: var(--bg-2);
  box-shadow: var(--shadow-frame);
}
.panes { display: flex; flex-direction: column; gap: 1rem; padding: 1rem; }
.pane { min-width: 0; padding: 1.1rem; border: 1px solid var(--line); border-radius: 14px; background: var(--bg); }
.pane-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 0.6rem; margin-bottom: 1rem; }
.pane-head h3 { font: 700 1.15rem/1.2 var(--font-display); letter-spacing: -0.02em; }
.pane-head .badge { background: color-mix(in srgb, var(--text) 8%, transparent); color: var(--text-2); }
.pane-head .badge--ok { background: color-mix(in srgb, var(--pos) 16%, transparent); color: var(--pos); }
.pane-note { margin-top: 0.9rem; color: var(--text-3); font-size: 0.8rem; }

.rows { display: grid; gap: 0.6rem; }
.row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 0.8rem;
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-2);
}
.row-ico {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: color-mix(in srgb, var(--ember) 14%, transparent);
  color: var(--ember-2);
}
.row-ico .ico { width: 18px; height: 18px; }
.row-main b { display: block; overflow: hidden; font: 500 0.86rem/1.3 var(--font-mono); text-overflow: ellipsis; white-space: nowrap; }
.row-main small { display: block; margin-top: 0.15rem; color: var(--text-3); font-size: 0.78rem; }
.status {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.3rem 0.65rem;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 600;
  white-space: nowrap;
}
.status .ico { width: 0.95em; height: 0.95em; }
.status--ok { background: color-mix(in srgb, var(--pos) 15%, transparent); color: var(--pos); }
.status--warn { background: var(--warn-bg); color: var(--warn-text); }

.recipe { width: 100%; border-collapse: collapse; font-size: 0.86rem; }
.recipe th, .recipe td { padding: 0.5rem 0; border-bottom: 1px dashed var(--line); font-weight: 400; text-align: left; }
.recipe td { color: var(--text-2); font-family: var(--font-mono); font-size: 0.78rem; text-align: right; }
.recipe td:last-child { min-width: 5.5rem; color: var(--text); }
.recipe tfoot th, .recipe tfoot td { padding-top: 0.75rem; border-top: 1px solid var(--line); border-bottom: 0; font-weight: 600; }
.recipe tfoot td:last-child { color: var(--ember-2); font-size: 0.95rem; }
.calc { margin-top: 1rem; }
.calc-stats { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0.6rem; }
.stat { padding: 0.7rem 0.85rem; border: 1px solid var(--line); border-radius: 12px; background: var(--bg-2); }
.stat small { display: block; color: var(--text-3); font: 500 0.68rem/1.2 var(--font-mono); letter-spacing: 0.06em; text-transform: uppercase; }
.stat b { display: block; margin-top: 0.3rem; font: 500 1.15rem/1.1 var(--font-mono); letter-spacing: -0.02em; }
.stat--margin { border-color: color-mix(in srgb, var(--crimson) 45%, var(--line)); }
.stat--margin b { color: var(--danger-text); }
.margin-bar { position: relative; height: 10px; margin-top: 1.7rem; border-radius: 999px; background: var(--bg-3); }
.margin-bar i {
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--ember-2), var(--crimson));
  transform: scaleX(var(--w));
  transform-origin: left;
}
.margin-bar .goal { position: absolute; top: -5px; bottom: -5px; left: 50%; width: 2px; background: var(--text); }
.margin-bar .goal em {
  position: absolute;
  top: -1.45rem;
  left: 50%;
  color: var(--text-2);
  font: 500 0.68rem/1 var(--font-mono);
  font-style: normal;
  transform: translateX(-50%);
  white-space: nowrap;
}

.recs { display: grid; gap: 0.6rem; }
.rec-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 0.8rem;
  padding: 0.8rem 0.95rem;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-2);
}
.rec-card--danger { border-color: color-mix(in srgb, var(--crimson) 45%, var(--line)); }
.dot { width: 9px; height: 9px; border-radius: 50%; background: var(--crimson); box-shadow: 0 0 12px var(--crimson); }
.rec-card--warn .dot { background: var(--amber); box-shadow: 0 0 12px var(--amber); }
.rec-main b { display: block; font-size: 0.88rem; font-weight: 600; }
.rec-main small { display: block; margin-top: 0.15rem; color: var(--text-3); font-size: 0.76rem; line-height: 1.4; }
.rec-val { color: var(--danger-text); font: 500 1rem/1 var(--font-mono); text-align: right; white-space: nowrap; }
.rec-val small { display: block; margin-top: 0.2rem; color: var(--text-3); font: 400 0.68rem var(--font-body); }
.rec-val--warn { color: var(--warn-text); font-size: 0.86rem; }

.sim { margin-top: 1rem; padding: 0.95rem 1rem; border: 1px solid var(--line); border-radius: 14px; background: var(--bg-2); }
.sim label { display: block; font-size: 0.84rem; font-weight: 600; }
.sim-row { display: flex; align-items: center; gap: 1rem; margin-top: 0.2rem; }
.sim output { min-width: 4.8rem; font: 500 1rem/1 var(--font-mono); text-align: right; }
.sim input[type="range"] {
  flex: 1;
  min-width: 0;
  height: 44px;
  margin: 0;
  background: transparent;
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}
.sim input[type="range"]::-webkit-slider-runnable-track {
  height: 6px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--ember) var(--fill, 25%), var(--bg-3) var(--fill, 25%));
}
.sim input[type="range"]::-moz-range-track {
  height: 6px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--ember) var(--fill, 25%), var(--bg-3) var(--fill, 25%));
}
.sim input[type="range"]::-webkit-slider-thumb {
  width: 22px;
  height: 22px;
  margin-top: -8px;
  border: 3px solid var(--ember);
  border-radius: 50%;
  background: var(--text);
  box-shadow: 0 0 0 6px color-mix(in srgb, var(--ember) 18%, transparent);
  -webkit-appearance: none;
  appearance: none;
}
.sim input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border: 3px solid var(--ember);
  border-radius: 50%;
  background: var(--text);
  box-shadow: 0 0 0 6px color-mix(in srgb, var(--ember) 18%, transparent);
}
.sim-stats { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 0.4rem 1rem; color: var(--text-2); font-size: 0.82rem; }
.sim-stats b { margin-left: 0.3rem; color: var(--text); font: 500 0.95rem/1 var(--font-mono); }
.sim-stats .is-good { color: var(--pos); }
.sim-stats .is-bad { color: var(--danger-text); }
.sim-note { margin-top: 0.6rem; color: var(--text-3); font-size: 0.74rem; }
.pane-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 44px;
  margin-top: 0.4rem;
  color: var(--ember-2);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
}
.pane-link .ico { transition: transform 0.3s var(--ease-out); }
.pane-link:hover .ico { transform: translateX(4px); }

.doc { position: absolute; width: clamp(108px, 13vw, 168px); will-change: transform; }
.doc-body {
  padding: 0.65rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: color-mix(in srgb, var(--bg-2) 92%, transparent);
  box-shadow: 0 18px 40px -18px rgba(0, 0, 0, 0.65);
}
.doc-head { display: flex; align-items: center; gap: 0.4rem; margin-bottom: 0.5rem; color: var(--text-2); }
.doc-head .ico { width: 14px; height: 14px; color: var(--ember-2); }
.doc-head b { overflow: hidden; font: 500 0.66rem/1.2 var(--font-mono); text-overflow: ellipsis; white-space: nowrap; }
.doc-body i { display: block; height: 5px; margin-top: 0.35rem; border-radius: 3px; background: var(--line); }
.doc-body i.short { width: 58%; }

/* Escena fija (JS activo) */
.how.is-scene .how-track { height: calc(var(--how-screens, 4.6) * 100vh); height: calc(var(--how-screens, 4.6) * 100svh); }
.how.is-scene .how-scene {
  position: sticky;
  top: 0;
  display: flex;
  height: 100vh;
  height: 100svh;
  padding-top: 76px;
  overflow: hidden;
}
.how.is-scene .how-grid { width: 100%; margin-block: auto; align-items: center; }
.how.is-scene .how-ambient { position: absolute; inset: 0; display: block; pointer-events: none; }
.how-ambient--a, .how-ambient--b { position: absolute; inset: 0; }
.how-ambient--a {
  background: radial-gradient(58% 60% at 28% 50%, var(--glow-b), transparent 72%),
    radial-gradient(50% 50% at 78% 60%, color-mix(in srgb, var(--crimson) 10%, transparent), transparent 70%);
}
.how-ambient--b {
  background: radial-gradient(60% 60% at 72% 48%, var(--glow-a), transparent 72%),
    radial-gradient(46% 50% at 22% 62%, color-mix(in srgb, var(--ember-2) 14%, transparent), transparent 70%);
}
.how.is-scene .docs { position: absolute; inset: 0; z-index: 3; display: block; pointer-events: none; }
.how.is-scene .how-stage { padding: clamp(1.4rem, 3.4vw, 3rem) clamp(1rem, 3.2vw, 2.6rem); }
.how.is-scene .panes { display: grid; padding: 0; gap: 0; }
.how.is-scene .pane {
  grid-area: 1 / 1;
  padding: clamp(1rem, 1.8vw, 1.5rem);
  border: 0;
  border-radius: 0;
  background: transparent;
}
.how.is-scene .step { opacity: 0.42; }
.how.is-scene .step:hover { opacity: 0.8; }
.how.is-scene .step.is-active {
  border-color: color-mix(in srgb, var(--ember) 45%, var(--line));
  background: color-mix(in srgb, var(--bg-2) 88%, transparent);
  opacity: 1;
}
.how.is-scene .step.is-active .step-num { color: var(--ember-2); }

@media (min-width: 1024px) {
  .how-grid { grid-template-columns: minmax(300px, 0.82fr) minmax(0, 1.5fr); gap: clamp(2rem, 4vw, 4.5rem); }
}

@media (max-width: 1023px) {
  .how.is-scene .how-grid { grid-template-columns: minmax(0, 1fr); gap: 0.6rem; }
  .how.is-scene .steps { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0.5rem; }
  .how.is-scene .step { grid-template-columns: minmax(0, 1fr); gap: 0.3rem; min-height: 48px; padding: 0.75rem 0.8rem; border-radius: 12px; }
  .how.is-scene .step-title { font-size: 0.84rem; }
  .how.is-scene .step-desc, .how.is-scene .step-tags, .how.is-scene .how-cta { display: none; }
  .how.is-scene .step-caption { display: block; margin-top: 0.7rem; color: var(--text-2); font-size: 0.92rem; line-height: 1.5; }
  .how.is-scene .step-caption b { display: block; margin-bottom: 0.2rem; color: var(--text); font: 700 1.05rem/1.2 var(--font-display); letter-spacing: -0.02em; }
  .how.is-scene .how-stage { padding: clamp(1rem, 4vw, 2rem) clamp(0.6rem, 3vw, 1.6rem) 0; }
  .how.is-scene .how-scene { padding-top: 84px; }
  .how.is-scene .how-stage { overflow: clip; }
  .how.is-scene .docs { top: 0.8rem; }
}

@media (max-width: 700px) {
  .how.is-scene .rec-main small,
  .how.is-scene .pane-note,
  .how.is-scene .sim-note { display: none; }
  .how.is-scene .pane { padding: 0.9rem; }
  .how.is-scene .pane-head { margin-bottom: 0.7rem; }
  .how.is-scene .sim { margin-top: 0.7rem; padding: 0.7rem 0.85rem; }
  .how.is-scene .sim input[type="range"] { height: 38px; }
  .step-num { display: none; }
  .row { gap: 0.6rem; padding: 0.6rem 0.65rem; }
  .row-ico { width: 30px; height: 30px; }
  .calc-stats { gap: 0.4rem; }
  .stat { padding: 0.55rem 0.6rem; }
  .stat b { font-size: 1rem; }
  .recipe .qty { display: none; }
  .rec-card { gap: 0.6rem; padding: 0.65rem 0.7rem; }
}

@media (max-height: 800px) {
  .how.is-scene .pane-note, .how.is-scene .sim-note { display: none; }
  .how.is-scene .row { padding-block: 0.5rem; }
  .how.is-scene .recipe th, .how.is-scene .recipe td { padding-block: 0.36rem; }
  .how.is-scene .rec-card { padding-block: 0.6rem; }
  .how.is-scene .sim { margin-top: 0.7rem; padding-block: 0.7rem; }
  .how.is-scene .sim input[type="range"] { height: 36px; }
}

@media (max-height: 700px) {
  .how.is-scene .rec-card:nth-child(3) { display: none; }
  .how.is-scene .pane-link, .how.is-scene .pane-head .badge { display: none; }
  .how.is-scene .how-intro { padding-block: 3rem 1.5rem; }
}