/* ============================================
   DESAFÍOS — listing page
   Plataforma premium de desafíos abiertos de IA.
   Coherente con el resto del sitio: paleta cyan
   + pink, glass cards, hover sutil, sin íconos
   extra ni elementos administrativos.
   ============================================ */

.desafios-hero {
  background:
    radial-gradient(ellipse 70% 50% at 50% 0%, rgba(0, 229, 255, 0.07), transparent 70%),
    radial-gradient(ellipse 60% 40% at 10% 50%, rgba(234, 64, 118, 0.06), transparent 70%);
  padding-top: clamp(120px, 14vw, 180px);
  padding-bottom: clamp(60px, 7vw, 100px);
  position: relative;
}
.desafios-hero::before {
  content: "";
  position: absolute;
  top: 0; left: 10%; right: 10%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(0, 229, 255, 0.3), transparent);
}
.desafios-hero .section__title {
  font-size: clamp(2.4rem, 5.2vw, 4.2rem);
  line-height: 1.04;
  letter-spacing: -0.025em;
}

/* Tres pilares debajo del hero — comunican valor antes de las tarjetas */
.desafios-hero__pillars {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 26px);
  max-width: 980px;
  margin: clamp(40px, 5vw, 64px) auto 0;
}
.desafios-hero__pillar {
  background: rgba(18, 18, 18, 0.55);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  padding: 22px 22px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: border-color 0.32s var(--ease-out), transform 0.32s var(--ease-out);
}
.desafios-hero__pillar:hover { border-color: var(--c-cyan); transform: translateY(-3px); }
.desafios-hero__pillar-num {
  display: inline-block;
  font-family: var(--f-display);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--c-cyan);
  margin-bottom: 10px;
}
.desafios-hero__pillar h3 {
  font-family: var(--f-display);
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}
.desafios-hero__pillar p { font-size: 13px; color: var(--c-muted); line-height: 1.55; }

@media (max-width: 720px) {
  .desafios-hero__pillars { grid-template-columns: 1fr; }
}

/* ============================================
   GRID DE DESAFÍOS — tarjetas premium
   ============================================ */
.desafios-grid-section { padding-top: clamp(40px, 6vw, 80px); padding-bottom: clamp(60px, 7vw, 100px); }
.desafios-grid-section__head { text-align: center; margin-bottom: clamp(36px, 4vw, 56px); }
.desafios-grid-section__head .section__title {
  font-size: clamp(1.8rem, 3.2vw, 2.4rem);
  letter-spacing: -0.015em;
}

.desafios-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: clamp(20px, 2.4vw, 32px);
  max-width: 1180px;
  margin: 0 auto;
}

.challenge-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 28px;
  background: rgba(18, 18, 18, 0.7);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  isolation: isolate;
  /* Microinteracción premium — lift + tinte cyan + box-shadow del color de marca */
  transition:
    transform 0.4s var(--ease-out),
    border-color 0.32s var(--ease-out),
    background 0.32s var(--ease-out),
    box-shadow 0.4s var(--ease-out);
}
.challenge-card::before {
  /* Aura interior que aparece al hover, palette-only */
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(135deg, rgba(0, 229, 255, 0.08), transparent 55%);
  opacity: 0;
  transition: opacity 0.4s var(--ease-out);
  z-index: -1;
  pointer-events: none;
}
.challenge-card:hover {
  transform: translateY(-6px);
  border-color: var(--c-cyan);
  background: rgba(18, 18, 18, 0.82);
  box-shadow:
    0 28px 60px -24px rgba(0, 229, 255, 0.4),
    inset 0 0 0 1px rgba(0, 229, 255, 0.16);
}
.challenge-card:hover::before { opacity: 1; }

.challenge-card__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  min-height: 56px;
}
.challenge-card__sponsor {
  display: inline-flex;
  align-items: center;
  height: 44px;
  max-width: 65%;
}
.challenge-card__sponsor img {
  max-height: 44px;
  width: auto;
  filter: grayscale(1) brightness(2);
  opacity: 0.9;
  transition: filter 0.3s var(--ease-out), opacity 0.3s var(--ease-out);
}
.challenge-card__sponsor span {
  font-family: var(--f-display);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--c-muted-2);
}
.challenge-card:hover .challenge-card__sponsor img { filter: grayscale(0) brightness(1); opacity: 1; }

/* Badge de estado — Abierto = cyan, Próximamente = ámbar suave (palette pink soft),
   Cerrado = gris muted. Sin íconos. */
.challenge-card__badge {
  flex-shrink: 0;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  padding: 6px 12px;
  border-radius: 999px;
  white-space: nowrap;
}
.challenge-card__badge--abierto {
  color: var(--c-cyan);
  background: var(--c-cyan-soft);
  border: 1px solid rgba(0, 229, 255, 0.32);
}
.challenge-card__badge--proximamente {
  color: var(--c-pink);
  background: rgba(234, 64, 118, 0.10);
  border: 1px solid rgba(234, 64, 118, 0.32);
}
.challenge-card__badge--cerrado {
  color: var(--c-muted-2);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--c-line);
}

.challenge-card__title {
  font-family: var(--f-display);
  font-size: clamp(20px, 2.2vw, 24px);
  font-weight: 700;
  letter-spacing: -0.015em;
  line-height: 1.18;
  color: var(--c-white);
}
.challenge-card__slogan {
  font-size: 15px;
  line-height: 1.45;
  color: var(--c-white);
  opacity: 0.92;
  font-weight: 500;
}
.challenge-card__desc { font-size: 13.5px; line-height: 1.6; color: var(--c-muted); }

.challenge-card__meta {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  padding: 14px 0;
  border-top: 1px dashed var(--c-line);
  border-bottom: 1px dashed var(--c-line);
  margin-top: auto;
}
.challenge-card__meta-item { display: flex; flex-direction: column; gap: 4px; }
.challenge-card__meta-label {
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--c-muted-2);
  font-weight: 600;
}
.challenge-card__meta-value {
  font-family: var(--f-display);
  font-size: 14px;
  font-weight: 700;
  color: var(--c-white);
  letter-spacing: -0.005em;
}

.challenge-card__cta {
  /* No full-width: cuando hay UNA sola card, el grid auto-fit la estira a
     ~1180px y un botón al 100% se ve desproporcionado. Lo limitamos y centramos.
     Con varias cards (más angostas) igual se ve bien. */
  align-self: center;
  width: 100%;
  max-width: 340px;
  justify-content: center;
  min-height: 48px;
}
.challenge-card__cta svg { transition: transform 0.3s var(--ease-out); }
.challenge-card:hover .challenge-card__cta svg { transform: translateX(3px); }

/* ============================================
   AVISO TRANSVERSAL — el requisito IA aplica a todos
   ============================================ */
.desafios-ai-note { padding-top: 0; padding-bottom: clamp(70px, 8vw, 110px); }
.desafios-ai-note__card {
  max-width: 880px;
  margin: 0 auto;
  padding: clamp(28px, 4vw, 44px) clamp(28px, 4vw, 48px);
  background:
    linear-gradient(135deg, rgba(0, 229, 255, 0.10), transparent 60%),
    rgba(18, 18, 18, 0.75);
  border: 1px solid rgba(0, 229, 255, 0.28);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  position: relative;
  overflow: hidden;
}
.desafios-ai-note__card::before {
  content: "";
  position: absolute;
  top: 0; left: 8%; right: 8%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--c-cyan), transparent);
}
.desafios-ai-note__tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--c-cyan);
  background: var(--c-cyan-soft);
  border: 1px solid rgba(0, 229, 255, 0.32);
  padding: 5px 12px;
  border-radius: 999px;
  margin-bottom: 16px;
}
.desafios-ai-note__card h2 {
  font-family: var(--f-display);
  font-size: clamp(1.4rem, 2.6vw, 2rem);
  font-weight: 700;
  letter-spacing: -0.015em;
  line-height: 1.2;
  margin-bottom: 14px;
}
.desafios-ai-note__card p { color: var(--c-muted); font-size: 15px; line-height: 1.62; max-width: 700px; }

@media (max-width: 640px) {
  .challenge-card { padding: 22px; }
  .challenge-card__meta { grid-template-columns: 1fr; }
}

/* Banner de confirmación de voto (redirección del backend con ?voto=). */
.desafios-vote-banner {
  margin: 0 0 24px;
  padding: 14px 18px;
  font-size: 14px;
  color: var(--c-white);
  background: rgba(234, 64, 118, 0.08);
  border: 1px solid rgba(234, 64, 118, 0.35);
  border-left: 3px solid var(--c-pink);
  border-radius: var(--radius-sm);
}
.desafios-vote-banner--ok {
  background: rgba(0, 229, 255, 0.08);
  border-color: rgba(0, 229, 255, 0.35);
  border-left-color: var(--c-cyan);
}