/* ==========================================================================
   PROSERMAT — Premium Buttons 2026
   --------------------------------------------------------------------------
   FASE 1 · Sistema unificado de botones (sección 17 del plan UX/UI).
   Convención BEM: .btn--primary, .btn--secondary, .btn--ghost, .btn--whatsapp
   Tamaños:        .btn--sm, .btn--lg
   Estados:        :hover, :active, :focus-visible, :disabled, .is-loading
   Modificadores:  .btn--icon-only, .btn--full

   IMPORTANTE: la clase legacy `.btn` (definida en styles.css) NO se modifica.
   Las nuevas variantes BEM coexisten — el HTML existente sigue funcionando.
   ========================================================================== */

/* ── Base reusable (sólo cuando se usa BEM `--variant`) ──────────────── */
.btn--primary,
.btn--secondary,
.btn--ghost,
.btn--whatsapp {
  /* Reset + layout */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2, 8px);
  position: relative;
  isolation: isolate;

  /* Tipografía */
  font-family: var(--font-body, inherit);
  font-size: var(--text-sm, 0.95rem);
  font-weight: var(--font-weight-semibold, 600);
  line-height: 1;
  letter-spacing: 0.01em;
  white-space: nowrap;
  text-decoration: none;

  /* Caja */
  padding: var(--space-3, 12px) var(--space-6, 24px);
  min-height: 44px;          /* touch target a11y */
  border-radius: var(--radius-pill, 999px);
  border: 1.5px solid transparent;
  background: transparent;
  color: inherit;
  cursor: pointer;
  user-select: none;
  -webkit-tap-highlight-color: transparent;

  /* Movimiento */
  transition:
    background-color var(--duration-fast, 150ms) var(--ease-out, ease-out),
    border-color    var(--duration-fast, 150ms) var(--ease-out, ease-out),
    color           var(--duration-fast, 150ms) var(--ease-out, ease-out),
    box-shadow      var(--duration-base, 220ms) var(--ease-out, ease-out),
    transform       var(--duration-fast, 150ms) var(--ease-out, ease-out);
}

/* ── Iconos dentro de buttons ────────────────────────────────────────── */
.btn--primary > svg,
.btn--secondary > svg,
.btn--ghost > svg,
.btn--whatsapp > svg {
  width: 1em;
  height: 1em;
  flex: 0 0 auto;
}

/* =====================================================================
   VARIANTE · PRIMARY  (acción principal verde institucional)
   ===================================================================== */
.btn--primary {
  background: var(--color-brand-600, #1f7a4d);
  color: #ffffff;
  border-color: var(--color-brand-600, #1f7a4d);
  box-shadow: var(--shadow-brand-sm, 0 4px 10px rgba(31, 122, 77, .22));
}
.btn--primary:hover {
  background: var(--color-brand-700, #1a7344);
  border-color: var(--color-brand-700, #1a7344);
  box-shadow: var(--shadow-brand-md, 0 10px 22px rgba(31, 122, 77, .26));
  transform: translateY(-1px);
}
.btn--primary:active {
  background: var(--color-brand-800, #155c38);
  border-color: var(--color-brand-800, #155c38);
  box-shadow: var(--shadow-brand-sm, 0 4px 10px rgba(31, 122, 77, .22));
  transform: translateY(0) scale(.98);
}
.btn--primary:focus-visible {
  outline: none;
  box-shadow:
    var(--shadow-brand-sm, 0 4px 10px rgba(31, 122, 77, .22)),
    var(--shadow-focus, 0 0 0 3px rgba(31, 122, 77, .35));
}

/* =====================================================================
   VARIANTE · SECONDARY  (acción complementaria, outline)
   ===================================================================== */
.btn--secondary {
  background: var(--surface-card, #ffffff);
  color: var(--color-brand-700, #1a7344);
  border-color: var(--color-brand-600, #1f7a4d);
  box-shadow: var(--shadow-xs, 0 1px 2px rgba(15, 23, 42, .04));
}
.btn--secondary:hover {
  background: var(--color-brand-50, #edfaf3);
  border-color: var(--color-brand-700, #1a7344);
  color: var(--color-brand-800, #155c38);
  box-shadow: var(--shadow-sm, 0 2px 4px rgba(15, 23, 42, .06));
  transform: translateY(-1px);
}
.btn--secondary:active {
  background: var(--color-brand-100, #d4f6e5);
  transform: translateY(0) scale(.98);
}
.btn--secondary:focus-visible {
  outline: none;
  box-shadow: var(--shadow-focus, 0 0 0 3px rgba(31, 122, 77, .35));
}

/* =====================================================================
   VARIANTE · GHOST  (acción terciaria, sin fondo)
   ===================================================================== */
.btn--ghost {
  background: transparent;
  color: var(--color-brand-700, #1a7344);
  border-color: transparent;
}
.btn--ghost:hover {
  background: var(--color-brand-50, #edfaf3);
  color: var(--color-brand-800, #155c38);
}
.btn--ghost:active {
  background: var(--color-brand-100, #d4f6e5);
  transform: scale(.98);
}
.btn--ghost:focus-visible {
  outline: none;
  background: var(--color-brand-50, #edfaf3);
  box-shadow: var(--shadow-focus, 0 0 0 3px rgba(31, 122, 77, .35));
}

/* =====================================================================
   VARIANTE · WHATSAPP  (CTA contacto, verde marca WA)
   ===================================================================== */
.btn--whatsapp {
  background: #25d366;
  color: #ffffff;
  border-color: #25d366;
  box-shadow: 0 4px 10px rgba(37, 211, 102, .26);
}
.btn--whatsapp:hover {
  background: #1ebe5b;
  border-color: #1ebe5b;
  box-shadow: 0 10px 22px rgba(37, 211, 102, .32);
  transform: translateY(-1px);
}
.btn--whatsapp:active {
  background: #18a44d;
  border-color: #18a44d;
  transform: translateY(0) scale(.98);
}
.btn--whatsapp:focus-visible {
  outline: none;
  box-shadow:
    0 4px 10px rgba(37, 211, 102, .26),
    0 0 0 3px rgba(37, 211, 102, .35);
}

/* =====================================================================
   TAMAÑOS
   ===================================================================== */
.btn--sm {
  font-size: var(--text-xs, 0.78rem);
  padding: var(--space-2, 8px) var(--space-4, 16px);
  min-height: 36px;
  border-radius: var(--radius-pill, 999px);
}
.btn--lg {
  font-size: var(--text-base, 1.05rem);
  padding: var(--space-4, 16px) var(--space-8, 32px);
  min-height: 56px;
  border-radius: var(--radius-pill, 999px);
  gap: var(--space-3, 12px);
}

/* =====================================================================
   MODIFICADORES
   ===================================================================== */
.btn--full {
  width: 100%;
  display: flex;
}
.btn--icon-only {
  padding: var(--space-3, 12px);
  min-width: 44px;
  aspect-ratio: 1;
  gap: 0;
}
.btn--icon-only.btn--sm {
  padding: var(--space-2, 8px);
  min-width: 36px;
}
.btn--icon-only.btn--lg {
  padding: var(--space-4, 16px);
  min-width: 56px;
}

/* =====================================================================
   ESTADOS GLOBALES
   ===================================================================== */
.btn--primary:disabled,
.btn--secondary:disabled,
.btn--ghost:disabled,
.btn--whatsapp:disabled,
.btn--primary[aria-disabled="true"],
.btn--secondary[aria-disabled="true"],
.btn--ghost[aria-disabled="true"],
.btn--whatsapp[aria-disabled="true"] {
  opacity: 0.55;
  cursor: not-allowed;
  pointer-events: none;
  transform: none !important;
  box-shadow: none !important;
}

/* Loading: spinner inline; usar <span class="btn__spinner"> dentro */
.btn--primary.is-loading,
.btn--secondary.is-loading,
.btn--ghost.is-loading,
.btn--whatsapp.is-loading {
  color: transparent !important;
  pointer-events: none;
}
.btn--primary.is-loading::after,
.btn--secondary.is-loading::after,
.btn--ghost.is-loading::after,
.btn--whatsapp.is-loading::after {
  content: '';
  position: absolute;
  inset: 50% auto auto 50%;
  width: 1.1em;
  height: 1.1em;
  margin: -0.55em 0 0 -0.55em;
  border: 2px solid currentColor;
  border-top-color: transparent;
  border-radius: 50%;
  color: var(--color-brand-700, #1a7344);
  animation: btn-spin var(--duration-slower, 480ms) linear infinite;
}
.btn--primary.is-loading::after,
.btn--whatsapp.is-loading::after {
  color: #ffffff;
}

@keyframes btn-spin {
  to { transform: rotate(360deg); }
}

/* =====================================================================
   REDUCED MOTION
   ===================================================================== */
@media (prefers-reduced-motion: reduce) {
  .btn--primary,
  .btn--secondary,
  .btn--ghost,
  .btn--whatsapp {
    transition: none;
  }
  .btn--primary:hover,
  .btn--secondary:hover,
  .btn--ghost:hover,
  .btn--whatsapp:hover,
  .btn--primary:active,
  .btn--secondary:active,
  .btn--ghost:active,
  .btn--whatsapp:active {
    transform: none;
  }
  .btn--primary.is-loading::after,
  .btn--secondary.is-loading::after,
  .btn--ghost.is-loading::after,
  .btn--whatsapp.is-loading::after {
    animation-duration: 1.4s;
  }
}