:root {
  --primary: #ff2f92;      /* rosa del congreso */
  --primary-dark: #cc216f;
  --accent: #00b4e6;       /* celeste de las cintas */
  --accent-warm: #ffd54b;  /* amarillo fecha */
  --text-main: #ffffff;
  --text-soft: rgba(255, 255, 255, 0.8);
  --bg-overlay: rgba(0, 0, 0, 0.45);
  --card-bg: rgba(0, 0, 0, 0.60);
  --border-soft: rgba(255, 255, 255, 0.15);
  --radius-lg: 18px;
  --transition-fast: 0.2s ease-out;
  --max-width: 1080px;
}

/* Reset mínimo */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
}

body {
  min-height: 100vh;
  font-family: "Fira Sans", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text-main);
  background-color: #000;
  background-image: url("fondo-mobile.jpeg");
  background-size: cover;
  background-position: center top;
  background-repeat: no-repeat;
  position: relative;
}

/* Overlay para mejorar legibilidad */
.page-overlay {
  position: fixed;
  inset: 0;
  background: radial-gradient(circle at top, rgba(255, 47, 146, 0.45), transparent 55%),
              linear-gradient(to bottom, rgba(0, 0, 0, 0.65), rgba(0, 0, 0, 0.95));
  pointer-events: none;
  z-index: -1;
}

@media (min-width: 768px) {
  body {
    background-image: url("fondo-PC.jpeg");
    background-attachment: fixed;
    background-position: center center;
  }
}

/* Layout principal */

.header {
  padding: 24px 16px 8px;
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: center;
}

.logo {
  max-width: 640px;
  width: 100%;
  height: auto;
}

/* Contenido principal */

.main-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 8px 16px 32px;
}

/* Hero */

.hero {
  text-align: center;
  margin-top: 8px;
  margin-bottom: 32px;
}

.hero-buttons {
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: center;
}

/* Botones */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: 999px;
  border: 0; /* <- sin borde por defecto */
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast),
              background-color var(--transition-fast), border-color var(--transition-fast),
              color var(--transition-fast);
  min-width: 220px;
  backdrop-filter: blur(6px);
}

.btn.primary {
  background: linear-gradient(135deg, var(--primary), var(--accent-warm));
  color: #1b0030;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
}

.btn.primary:hover,
.btn.primary:focus-visible {
  background: linear-gradient(135deg, var(--primary-dark), var(--accent-warm));
  transform: translateY(-1px);
  box-shadow: 0 14px 32px rgba(0, 0, 0, 0.55);
}

/* ahora sí los otros tienen borde explícito */
.btn.secondary {
  background-color: var(--card-bg);
  color: var(--text-main);
  border: 1px solid var(--border-soft);
}

.btn.secondary:hover,
.btn.secondary:focus-visible {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.btn.outline {
  background-color: transparent;
  color: var(--accent-warm);
  border: 1px solid var(--accent-warm);
}

.btn.outline:hover,
.btn.outline:focus-visible {
  background-color: rgba(0, 0, 0, 0.6);
}

/* Secciones */

.section-title {
  text-align: left;
  margin-bottom: 12px;
}

.section-title h2 {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--text-soft);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* Video responsivo */

.video-section {
  margin-bottom: 32px;
}

.video-wrapper {
  position: relative;
  width: 100%;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: rgba(0, 0, 0, 0.7);
  box-shadow: 0 14px 30px rgba(0, 0, 0, 0.6);
}

.video-wrapper::before {
  content: "";
  display: block;
  padding-top: 56.25%; /* 16:9 */
}

.video-wrapper iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

/* Sponsors */

.sponsors-section {
  margin-bottom: 32px;
}

.sponsors-wrapper {
  border-radius: var(--radius-lg);
  padding: 14px 18px;
  background-color: var(--card-bg);
  border: 1px solid var(--border-soft);
  display: flex;
  justify-content: center;
  align-items: center;
}

.sponsors-image {
  width: 100%;
  height: auto;
  max-height: 120px;
  object-fit: contain;
}

/* Contacto */

.contact-section {
  margin-bottom: 40px;
}

.contact-grid {
  display: grid;
  gap: 14px;
}

.contact-card {
  display: flex;
  flex-direction: column;
  padding: 12px 14px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-soft);
  background-color: var(--card-bg);
  text-decoration: none;
  color: var(--text-main);
  transition: transform var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast), box-shadow var(--transition-fast);
}

.contact-card:hover,
.contact-card:focus-visible {
  transform: translateY(-2px);
  border-color: var(--accent);
  background-color: rgba(0, 0, 0, 0.78);
  box-shadow: 0 10px 26px rgba(0, 0, 0, 0.55);
}

.contact-label {
  font-weight: 500;
  font-size: 0.95rem;
}

.contact-sub {
  font-size: 0.8rem;
  color: var(--text-soft);
  margin-top: 2px;
}

/* Footer */

.footer {
  padding: 16px;
  text-align: center;
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.7);
}

.footer a {
  color: rgba(255, 255, 255, 0.7);
  text-decoration: underline;
  text-decoration-style: dotted;
}

.footer a:hover,
.footer a:focus-visible {
  color: var(--accent-warm);
}

/* Lightbox */

.lightbox {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.lightbox.active {
  display: flex;
}

.lightbox-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
}

.lightbox-content {
  position: relative;
  max-width: 960px;
  width: 100%;
  margin: 16px;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.lightbox-content img {
  width: 100%;
  max-height: 90vh;
  object-fit: contain;
  border-radius: 10px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.8);
}

.lightbox-close {
  position: absolute;
  top: -14px;
  right: -10px;
  background: #000;
  border-radius: 999px;
  border: 1px solid var(--border-soft);
  font-size: 28px;
  width: 40px;
  height: 40px;
  color: var(--text-main);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition-fast), transform var(--transition-fast);
}

.lightbox-close:hover {
  background-color: var(--primary-dark);
  transform: translateY(-1px);
}

.lightbox-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(0, 0, 0, 0.7);
  border-radius: 999px;
  border: 1px solid var(--border-soft);
  color: var(--text-main);
  cursor: pointer;
  font-size: 26px;
  width: 38px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  transition: background-color var(--transition-fast), transform var(--transition-fast);
}

.lightbox-nav:hover {
  background-color: var(--primary-dark);
  transform: translateY(-50%) scale(1.05);
}

.lightbox-nav.prev {
  left: -6px;
}

.lightbox-nav.next {
  right: -6px;
}

.lightbox-counter {
  position: absolute;
  bottom: -26px;
  right: 4px;
  font-size: 0.8rem;
  color: var(--text-soft);
}

/* Preload container oculto */

.preload-container {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
  opacity: 0;
  pointer-events: none;
}

/* Breakpoints */

@media (min-width: 600px) {
  .hero-buttons {
    flex-direction: row;
    justify-content: center;
  }

  .btn {
    min-width: auto;
  }

  .contact-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .main-content {
    padding-bottom: 48px;
  }

  .video-section,
  .sponsors-section,
  .contact-section {
    margin-bottom: 40px;
  }
}