/* ============================================================
   STAIRCASE — Zigzag con números decorativos, acento vertical,
   clip-path reveal en imágenes, border-radius asimétrico
   ============================================================ */

.staircase {
  padding-block: var(--section-py-lg);
  padding-inline: var(--section-px);
  background-color: var(--dark);
  overflow: hidden;
}

.staircase__container {
  max-width: var(--container-max);
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  /* Espaciado deliberadamente irregular entre bloques */
  gap: 0;
}

/* ── Bloque individual ───────────────────────────────────────── */

.staircase__block {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  column-gap: 4rem;
  align-items: start;
}

/* Espaciado asimétrico: los tres bloques tienen padding-top diferente */
.staircase__block:nth-child(1) { padding-block: 0 5rem; }
.staircase__block:nth-child(2) { padding-block: 0 7rem; }
.staircase__block:nth-child(3) { padding-block: 0 2rem; }

/* Efecto escalera: la segunda columna de cada fila baja */
.staircase__block:nth-child(odd)  .staircase__text  { order: 1; padding-top: 0; }
.staircase__block:nth-child(odd)  .staircase__image { order: 2; padding-top: 5rem; }

.staircase__block:nth-child(even) .staircase__image { order: 1; padding-top: 0; }
.staircase__block:nth-child(even) .staircase__text  { order: 2; padding-top: 5rem; }

/* ── Número decorativo de fondo ──────────────────────────────── */
/* Se añade desde main.js como <span class="staircase__bg-num"> */

.staircase__bg-num {
  position: absolute;
  font-family: var(--font-heading);
  font-size: clamp(120px, 16vw, 220px);
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.06em;
  color: var(--teal-300);
  opacity: 0.045;
  top: -0.15em;
  left: -0.05em;
  pointer-events: none;
  user-select: none;
  z-index: 0;
}

.staircase__block:nth-child(even) .staircase__bg-num {
  left: auto;
  right: -0.05em;
}

/* ── Columna de texto ────────────────────────────────────────── */

.staircase__text {
  position: relative;
  z-index: 1;
  max-width: 460px;
}

/* Alinear texto al borde del grid */
.staircase__block:nth-child(odd)  .staircase__text { margin-inline-start: auto; }
.staircase__block:nth-child(even) .staircase__text { margin-inline-end: auto; }

/* Mono label */
.staircase__label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--teal-300);
  margin-bottom: 1.25rem;
}

/* Título con acento vertical a la izquierda */
.staircase__title-wrap {
  position: relative;
  padding-inline-start: 1.1rem;
  margin-bottom: 1.1rem;
}

.staircase__title-wrap::before {
  content: '';
  position: absolute;
  inset-inline-start: 0;
  inset-block: 0.1em 0.1em;
  width: 3px;
  background: var(--teal-500);
}

.staircase__title {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 2.8vw, 2rem);
  font-weight: 700;
  color: var(--neutral-100);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.staircase__body {
  font-size: 1rem;
  font-weight: 300;
  color: var(--neutral-200);
  line-height: 1.8;
}

/* ── Columna de imagen ───────────────────────────────────────── */

.staircase__image {
  position: relative;
  z-index: 1;
}

/* El clip-path reveal se aplica al wrapper de imagen desde base.css (.reveal-clip) */

/* Placeholder con trama de puntos y border-radius asimétrico */
.staircase__image-placeholder {
  width: 100%;
  aspect-ratio: 4 / 3;
  background-color: var(--dark-soft);
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 0.75rem;
}

/* Border-radius asimétrico por paridad del bloque */
.staircase__block:nth-child(odd)  .staircase__image-placeholder {
  border-radius: var(--radius-img);     /* 2px 20px 20px 2px */
}
.staircase__block:nth-child(even) .staircase__image-placeholder {
  border-radius: var(--radius-img-alt); /* 20px 2px 2px 20px */
}

/* Trama de puntos (halftone-like) */
.staircase__image-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(
    circle,
    rgba(var(--teal-300-rgb), 0.13) 1px,
    transparent 1px
  );
  background-size: 22px 22px;
  z-index: 0;
}

/* Luz suave de fondo */
.staircase__image-placeholder::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(
    ellipse at 30% 60%,
    rgba(var(--teal-300-rgb), 0.06) 0%,
    transparent 65%
  );
  z-index: 0;
}

/* Borde izquierdo de acento en las placeholders */
.staircase__block:nth-child(odd)  .staircase__image-placeholder {
  border-left: 3px solid rgba(var(--teal-300-rgb), 0.25);
}
.staircase__block:nth-child(even) .staircase__image-placeholder {
  border-right: 3px solid rgba(var(--blue-300-rgb), 0.2);
}

.staircase__img-label {
  position: relative;
  z-index: 1;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(var(--teal-300-rgb), 0.35);
}

/* Sustituir placeholder por imagen real:
   <img src="assets/images/tu-foto.webp" alt="..." class="staircase__real-img"> */
.staircase__real-img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
  border-radius: 10px;
}

/* ── Responsive ──────────────────────────────────────────────── */

@media (max-width: 860px) {
  .staircase__block {
    column-gap: 2.5rem;
  }
  .staircase__block:nth-child(odd)  .staircase__image,
  .staircase__block:nth-child(even) .staircase__image {
    padding-top: 3rem;
  }
  .staircase__block:nth-child(even) .staircase__text {
    padding-top: 3rem;
  }
}

@media (max-width: 640px) {
  .staircase {
    padding-block: var(--section-py);
  }

  .staircase__block {
    grid-template-columns: 1fr;
    row-gap: 2rem;
  }

  .staircase__block:nth-child(1),
  .staircase__block:nth-child(2),
  .staircase__block:nth-child(3) {
    padding-block: 0 3.5rem;
  }

  .staircase__block:nth-child(odd)  .staircase__text,
  .staircase__block:nth-child(even) .staircase__text {
    order: 1; padding-top: 0; max-width: 100%; margin-inline: 0;
  }

  .staircase__block:nth-child(odd)  .staircase__image,
  .staircase__block:nth-child(even) .staircase__image {
    order: 2; padding-top: 0;
  }

  .staircase__bg-num {
    font-size: clamp(80px, 22vw, 120px);
  }
}