```css
/* ============================================================
   CLASES.CSS
   Estilos específicos para la página de clases.
   Requiere GLOBAL.CSS antes de este archivo.
   ============================================================ */


/* ============================================================
   HERO
   ============================================================ */

.clases-hero {
  position: relative;
  min-height: 100vh;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: center;
  gap: clamp(2rem, 5vw, 4rem);

  padding: 8rem 8% 6rem;

  background: var(--dark);
  overflow: hidden;
  isolation: isolate;
}

/* Textura del hero */

.clases-hero::before {
  content: '';
  position: absolute;
  inset: 0;

  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='300' height='300' filter='url(%23noise)' opacity='0.04'/%3E%3C/svg%3E");

  pointer-events: none;
  z-index: -1;
}


/* ===== Hero eyebrow ===== */

.clases-hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;

  margin-bottom: 1.5rem;
  padding: 6px 16px;

  border: 1px solid rgba(163, 192, 55, 0.4);
  border-radius: 100px;

  background: rgba(163, 192, 55, 0.2);

  color: var(--green);

  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  line-height: 1;
  text-transform: uppercase;
}


/* ===== Hero title ===== */

.clases-hero-title {
  max-width: 850px;
  margin-bottom: 1.5rem;

  color: white;

  font-size: clamp(3.5rem, 7vw, 6.5rem);
  font-weight: 900;
  line-height: 0.95;
  letter-spacing: -0.04em;
}

.clases-hero-title span {
  color: var(--green);
}


/* ===== Hero description ===== */

.clases-hero-sub {
  max-width: 480px;
  margin-bottom: 2.5rem;

  color: rgba(255, 255, 255, 0.65);

  font-size: 1.05rem;
  line-height: 1.75;
}


/* ===== Hero statistics ===== */

.clases-hero-stats {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.hero-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hero-stat strong {
  color: white;

  font-size: clamp(2rem, 4vw, 2.4rem);
  font-weight: 900;
  line-height: 1;
}

.hero-stat span {
  color: rgba(255, 255, 255, 0.4);

  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.hero-stat-divider {
  width: 1px;
  height: 40px;

  background: rgba(255, 255, 255, 0.15);
}


/* ============================================================
   HERO — DECORACIÓN
   ============================================================ */

.clases-hero-deco {
  position: relative;

  display: flex;
  align-items: center;
  justify-content: center;

  min-height: 480px;
}

.deco-circle {
  position: absolute;

  border-radius: 50%;
  pointer-events: none;
}

.deco-c1 {
  width: 360px;
  height: 360px;

  background: rgba(163, 192, 55, 0.08);
  border: 2px solid rgba(163, 192, 55, 0.2);
}

.deco-c2 {
  top: 40px;
  right: 20px;

  width: 240px;
  height: 240px;

  background: rgba(85, 176, 210, 0.1);
  border: 2px solid rgba(85, 176, 210, 0.25);
}

.deco-c3 {
  bottom: 60px;
  left: 30px;

  width: 120px;
  height: 120px;

  background: rgba(204, 102, 153, 0.15);
  border: 2px solid rgba(204, 102, 153, 0.3);
}

.deco-number {
  position: absolute;

  color: rgba(255, 255, 255, 0.04);

  font-size: clamp(10rem, 18vw, 14rem);
  font-weight: 900;
  line-height: 1;

  user-select: none;
  pointer-events: none;
}


/* ============================================================
   INTRO — FASES
   ============================================================ */

.fases-intro {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;

  padding: 3rem 8%;

  background: var(--cream);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.fases-intro-inner {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.fases-intro-label {
  flex-shrink: 0;

  color: #aaa;

  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.fases-intro p {
  max-width: 480px;

  color: #666;

  font-size: 0.95rem;
  line-height: 1.5;
}


/* ============================================================
   TIMELINE
   ============================================================ */

.fases-timeline {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.fase-dot {
  width: 14px;
  height: 14px;

  flex-shrink: 0;
  border-radius: 50%;
}

.fase-dot--green {
  background: var(--green);
}

.fase-dot--blue {
  background: var(--blue);
}

.fase-dot--pink {
  background: var(--pink);
}

.fase-line {
  width: 48px;
  height: 2px;

  background: rgba(0, 0, 0, 0.12);
}


/* ============================================================
   FASE SECTION
   ============================================================ */

.fase-section {
  padding: 0 0 5rem;

  background: var(--white);
}

/*
   Se recomienda agregar la clase:
   .fase-section--cream
   cuando quieras una fase con fondo crema.
*/

.fase-section--cream {
  background: var(--cream);
}


/* ============================================================
   HEADER DE FASE
   ============================================================ */

.fase-header {
  margin-bottom: 0;
  padding: 3.5rem 8%;
}

.fase-header--green {
  background:
    linear-gradient(
      to right,
      rgba(163, 192, 55, 0.12) 0%,
      transparent 60%
    );

  border-left: 6px solid var(--green);
}

.fase-header--blue {
  background:
    linear-gradient(
      to right,
      rgba(85, 176, 210, 0.12) 0%,
      transparent 60%
    );

  border-left: 6px solid var(--blue);
}

.fase-header--pink {
  background:
    linear-gradient(
      to right,
      rgba(204, 102, 153, 0.12) 0%,
      transparent 60%
    );

  border-left: 6px solid var(--pink);
}

.fase-header-inner {
  display: flex;
  align-items: center;
  gap: 2rem;

  max-width: 1100px;
  margin: 0 auto;
}

.fase-number {
  flex-shrink: 0;

  padding: 6px 18px;

  border-radius: 100px;

  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0.2em;
  line-height: 1;
  text-transform: uppercase;
  white-space: nowrap;
}

.fase-header--green .fase-number {
  background: var(--green);
  color: white;
}

.fase-header--blue .fase-number {
  background: var(--blue);
  color: white;
}

.fase-header--pink .fase-number {
  background: var(--pink);
  color: white;
}

.fase-header-text {
  min-width: 0;
}

.fase-header-text h2 {
  margin-bottom: 0.25rem;

  color: var(--dark);

  font-size: clamp(1.3rem, 2.5vw, 1.9rem);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.fase-header-text span {
  color: #aaa;

  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}


/* ============================================================
   GRID DE ACTIVIDADES
   ============================================================ */

.actividades-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.2rem;

  width: min(1100px, 84%);
  margin: 0 auto;
  padding: 2rem 0;
}


/* ============================================================
   TARJETA DE ACTIVIDAD
   ============================================================ */

.actividad-card {
  position: relative;

  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: 1.2rem;

  min-width: 0;
  padding: 1.4rem 1.6rem;

  overflow: hidden;

  background: white;
  border: 1px solid rgba(0, 0, 0, 0.07);
  border-radius: 18px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.05);

  color: var(--dark);
  text-decoration: none;

  transition:
    transform 0.25s ease,
    box-shadow 0.25s ease,
    border-color 0.25s ease;
}


/* Indicador lateral */

.actividad-card::before {
  content: '';

  position: absolute;
  inset: 0 auto 0 0;

  width: 0;

  background: var(--green);
  border-radius: 18px 0 0 18px;

  transition: width 0.3s ease;
}

.actividad-card:hover {
  transform: translate3d(4px, -4px, 0);

  border-color: transparent;

  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.12);

  color: var(--dark);
}

.actividad-card:hover::before {
  width: 4px;
}


/* ===== Número ===== */

.actividad-num {
  display: flex;
  align-items: center;
  justify-content: center;

  width: 44px;
  height: 44px;

  flex-shrink: 0;

  border-radius: 12px;

  font-size: 0.85rem;
  font-weight: 900;
}


/* ===== Contenido ===== */

.actividad-body {
  min-width: 0;
}

.actividad-body h3 {
  margin-bottom: 3px;

  overflow: hidden;

  color: var(--dark);

  font-size: 0.95rem;
  font-weight: 900;

  white-space: nowrap;
  text-overflow: ellipsis;
}

.actividad-body p {
  overflow: hidden;

  color: #999;

  font-size: 0.8rem;
  font-weight: 600;

  white-space: nowrap;
  text-overflow: ellipsis;
}


/* ===== Tag ===== */

.actividad-tag {
  flex-shrink: 0;

  padding: 4px 10px;

  border-radius: 100px;

  font-size: 0.68rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  line-height: 1;
  text-transform: uppercase;
}


/* ===== Arrow ===== */

.actividad-arrow {
  flex-shrink: 0;

  color: #ddd;

  font-size: 1.1rem;
  font-weight: 900;

  transition:
    color 0.2s ease,
    transform 0.2s ease;
}

.actividad-card:hover .actividad-arrow {
  color: var(--dark);
  transform: translateX(4px);
}


/* ============================================================
   CTA FINAL
   ============================================================ */

.clases-cta {
  position: relative;

  padding: 6rem 8%;

  overflow: hidden;

  background: var(--dark);

  text-align: center;
  isolation: isolate;
}

.clases-cta::before {
  content: '';

  position: absolute;
  top: -100px;
  left: 50%;

  width: 600px;
  height: 600px;

  transform: translateX(-50%);

  border-radius: 50%;

  background: rgba(163, 192, 55, 0.06);

  pointer-events: none;
  z-index: -1;
}

.clases-cta-inner {
  position: relative;
  z-index: 1;
}


/* ============================================================
   ACCESSIBILITY
   ============================================================ */

.actividad-card:focus-visible,
.clases-hero a:focus-visible,
.clases-cta a:focus-visible {
  outline: 3px solid var(--yellow);
  outline-offset: 4px;
}


/* ============================================================
   RESPONSIVE — TABLET
   ============================================================ */

@media (max-width: 1100px) {

  .actividades-grid {
    grid-template-columns: 1fr;
  }

}


/* ============================================================
   RESPONSIVE — TABLET / MOBILE
   ============================================================ */

@media (max-width: 900px) {

  /* Hero */

  .clases-hero {
    grid-template-columns: 1fr;

    min-height: auto;

    padding: 7rem 6% 4rem;
  }

  .clases-hero-deco {
    display: none;
  }


  /* Intro */

  .fases-intro {
    flex-direction: column;
    align-items: flex-start;

    padding: 2rem 6%;
  }

  .fases-intro-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.75rem;
  }


  /* Fase */

  .fase-header {
    padding: 2.5rem 6%;
  }

  .fase-header-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 1rem;
  }


  /* Actividades */

  .actividades-grid {
    width: auto;
    padding: 1.5rem 6%;
  }


  /* CTA */

  .clases-cta {
    padding: 4rem 6%;
  }

}


/* ============================================================
   RESPONSIVE — MOBILE
   ============================================================ */

@media (max-width: 600px) {

  .clases-hero {
    padding-top: 6rem;
  }

  .clases-hero-title {
    font-size: clamp(2.8rem, 14vw, 4rem);
  }

  .clases-hero-sub {
    font-size: 0.95rem;
  }


  /* Stats */

  .clases-hero-stats {
    gap: 1.25rem;
  }

  .hero-stat strong {
    font-size: 1.8rem;
  }

  .hero-stat span {
    font-size: 0.65rem;
  }

  .hero-stat-divider {
    height: 32px;
  }


  /* Timeline */

  .fases-timeline {
    width: 100%;
  }

  .fase-line {
    flex: 1;
  }


  /* Activity card */

  .actividad-card {
    grid-template-columns: auto minmax(0, 1fr) auto;

    padding: 1.1rem 1.2rem;
  }

  .actividad-tag {
    display: none;
  }

  .actividad-num {
    width: 40px;
    height: 40px;

    border-radius: 10px;
  }

  .actividad-body h3 {
    font-size: 0.88rem;
  }

  .actividad-body p {
    font-size: 0.75rem;
  }


  /* Fase */

  .fase-header-text h2 {
    font-size: 1.2rem;
  }

}


/* ============================================================
   REDUCIR MOVIMIENTO
   ============================================================ */

@media (prefers-reduced-motion: reduce) {

  .actividad-card,
  .actividad-card::before,
  .actividad-arrow {
    transition: none;
  }

  .actividad-card:hover {
    transform: none;
  }

  .actividad-card:hover .actividad-arrow {
    transform: none;
  }

}
```