/*
 * chat-entrance.css — Animación de entrada del Chat IA (solo index.html)
 * Especificación: Kinik Home — AI Chat Entrance Animation
 *
 * Principio visual: el contenido emerge desde abajo hacia arriba (fade +
 * translate + máscara de gradiente). Nada de partículas, opciones de lienzo
 * ni librerías de terceros. Animación única al cargar; idle después.
 */

:root {
  /* Easing premium de entrada (spec §5) */
  --ease-chat: cubic-bezier(0.22, 1, 0.36, 1);
  /* Desplazamiento vertical del reveal (se reduce en mobile, spec §13) */
  --chat-rise-distance: 18px;
}

/* ─────────────────────────────────────────────
   1. Contenedor — Bottom-to-Top fade reveal
   ───────────────────────────────────────────── */
#lead-chat .chat-panel {
  animation:
    chat-panel-rise 600ms var(--ease-chat) 150ms both,
    chat-panel-mask 600ms var(--ease-chat) 150ms both;
}

@keyframes chat-panel-rise {
  from {
    opacity: 0;
    transform: translateY(var(--chat-rise-distance, 18px));
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Máscara vertical: una banda de contenido visible que se expande de arriba
   hacia abajo mientras el panel asciende. Estado final 100% opaco. */
@keyframes chat-panel-mask {
  from {
    -webkit-mask-image: linear-gradient(
      to top,
      transparent 0%,
      transparent 84%,
      #000 94%,
      #000 100%
    );
    mask-image: linear-gradient(
      to top,
      transparent 0%,
      transparent 84%,
      #000 94%,
      #000 100%
    );
  }
  to {
    -webkit-mask-image: linear-gradient(to top, #000 0%, #000 25%, #000 75%, #000 100%);
    mask-image: linear-gradient(to top, #000 0%, #000 25%, #000 75%, #000 100%);
  }
}

/* ─────────────────────────────────────────────
   2. Header — Kinik AI
   ───────────────────────────────────────────── */
.chat-panel__header {
  display: flex;
  align-items: center;
  padding: var(--space-3) var(--space-4);
  background: var(--bg-subtle);
  border-bottom: var(--border-thin) solid var(--border-color);
}

.chat-panel__ai-name {
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semibold);
  letter-spacing: var(--tracking-wide);
}

/* ─────────────────────────────────────────────
   3. Typing indicator (● ● ●) — solo inicial
   ───────────────────────────────────────────── */
.chat-typing--entrance {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  animation: chat-typing-bubble 600ms ease 750ms both;
}

.chat-typing__dot {
  width: 6px;
  height: 6px;
  border-radius: var(--radius-full);
  background: var(--color-brand-blue);
  opacity: 0;
  animation: chat-typing-dot 180ms ease both;
}

.chat-typing__dot:nth-child(1) {
  animation-delay: 760ms;
}

.chat-typing__dot:nth-child(2) {
  animation-delay: 880ms;
}

.chat-typing__dot:nth-child(3) {
  animation-delay: 1000ms;
}

@keyframes chat-typing-dot {
  to {
    opacity: 1;
  }
}

@keyframes chat-typing-bubble {
  0% {
    opacity: 0;
    transform: translateY(6px);
  }
  30% {
    opacity: 1;
    transform: translateY(0);
  }
  82% {
    opacity: 1;
    transform: translateY(0);
  }
  100% {
    opacity: 0;
    transform: translateY(0);
  }
}

/* ─────────────────────────────────────────────
   4. Mensaje inicial — reveal bottom-to-top
   ───────────────────────────────────────────── */
.chat-greeting {
  animation: chat-greeting-bubble 300ms var(--ease-chat) 1500ms both;
}

.chat-greeting__line {
  display: block;
}

.chat-greeting__line--later {
  margin-top: var(--space-2);
  animation: chat-element-rise 300ms var(--ease-chat) both;
}

@keyframes chat-greeting-bubble {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes chat-element-rise {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ─────────────────────────────────────────────
   5. Suggested actions — stagger 80ms
   ───────────────────────────────────────────── */
.chat-suggestions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  align-self: flex-start;
  padding-top: var(--space-1);
}

.chat-suggestion {
  appearance: none;
  border: var(--border-thin) solid var(--border-color-strong);
  background: var(--bg-surface);
  color: var(--text-secondary);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  line-height: var(--leading-normal);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-full);
  cursor: pointer;
  animation: chat-element-rise 280ms var(--ease-chat) both;
  transition:
    border-color var(--duration-fast) var(--ease-default),
    color var(--duration-fast) var(--ease-default),
    transform var(--duration-fast) var(--ease-default);
}

.chat-suggestion:hover {
  border-color: var(--color-brand-blue);
  color: var(--text-brand);
  transform: translateY(-1px);
}

.chat-suggestion:focus-visible {
  outline: 2px solid var(--border-color-focus);
  outline-offset: 2px;
}

/* ─────────────────────────────────────────────
   6. Responsive — desplazamiento reducido en mobile
   ───────────────────────────────────────────── */
@media (max-width: 640px) {
  :root {
    --chat-rise-distance: 10px;
  }
}

/* ─────────────────────────────────────────────
   7. Accessibility — prefers-reduced-motion
   ───────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  #lead-chat .chat-panel {
    animation: none;
    opacity: 1;
    transform: none;
    -webkit-mask-image: none;
    mask-image: none;
  }

  .chat-typing--entrance,
  .chat-typing__dot,
  .chat-greeting,
  .chat-greeting__line--later,
  .chat-suggestion {
    animation: none !important;
    opacity: 1 !important;
    transform: none !important;
  }
}