:root {
  --fondo: #f4f5f2;
  --superficie: #ffffff;
  --texto: #1c1f1d;
  --tenue: #6b716d;
  --borde: #dfe2dd;
  --acento: #0f766e;
  --acento-texto: #ffffff;
  --burbuja-yo: #0f766e;
  --burbuja-yo-texto: #ffffff;
  --chip: #e6f2ef;
  --chip-texto: #0b5a54;
  --error: #b42318;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --fondo: #121513;
    --superficie: #1c201e;
    --texto: #e7eae8;
    --tenue: #9aa19d;
    --borde: #2d3330;
    --acento: #2dd4bf;
    --acento-texto: #06201d;
    --burbuja-yo: #14544e;
    --burbuja-yo-texto: #e7f7f4;
    --chip: #183430;
    --chip-texto: #9be7da;
    --error: #f97066;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

html, body { height: 100%; margin: 0; }

body {
  display: flex;
  flex-direction: column;
  background: var(--fondo);
  color: var(--texto);
  font: 16px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

header {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: calc(12px + env(safe-area-inset-top)) 16px 12px;
  border-bottom: 1px solid var(--borde);
  background: var(--superficie);
}
header h1 { margin: 0; font-size: 18px; letter-spacing: .08em; color: var(--acento); }
header span { color: var(--tenue); font-size: 14px; }

#chat {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-width: 720px;
  width: 100%;
  margin: 0 auto;
}

.vacio { margin: auto; text-align: center; color: var(--tenue); max-width: 280px; }

.msg {
  max-width: 85%;
  padding: 9px 13px;
  border-radius: 16px;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.msg.user {
  align-self: flex-end;
  background: var(--burbuja-yo);
  color: var(--burbuja-yo-texto);
  border-bottom-right-radius: 4px;
}
.msg.assistant {
  align-self: flex-start;
  background: var(--superficie);
  border: 1px solid var(--borde);
  border-bottom-left-radius: 4px;
}
.msg.error { color: var(--error); }
.msg img { display: block; max-width: 220px; max-height: 220px; border-radius: 10px; margin-bottom: 6px; }

.chips { display: flex; flex-wrap: wrap; gap: 6px; align-self: flex-start; max-width: 85%; }
.chip {
  font-size: 13px;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--chip);
  color: var(--chip-texto);
}
.chip.eliminado, .chip.olvidada { text-decoration: line-through; opacity: .75; }

.escribiendo { color: var(--tenue); font-style: italic; }

#composer {
  border-top: 1px solid var(--borde);
  background: var(--superficie);
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
}
#composer .fila { display: flex; align-items: flex-end; gap: 8px; max-width: 720px; margin: 0 auto; }

textarea {
  flex: 1;
  resize: none;
  max-height: 140px;
  padding: 10px 14px;
  border: 1px solid var(--borde);
  border-radius: 20px;
  background: var(--fondo);
  color: var(--texto);
  font: inherit;
}
textarea:focus { outline: 2px solid var(--acento); outline-offset: -1px; }

.boton-icono {
  flex: none;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--tenue);
  cursor: pointer;
}
.boton-icono svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linejoin: round; }
.boton-icono.enviar { background: var(--acento); color: var(--acento-texto); }
.boton-icono:disabled { opacity: .5; cursor: default; }
.boton-icono.grabando { background: var(--error); color: #fff; animation: latido 1.2s ease-in-out infinite; }
@keyframes latido { 50% { transform: scale(1.08); } }
@media (prefers-reduced-motion: reduce) { .boton-icono.grabando { animation: none; } }

#vista-previa { position: relative; width: max-content; max-width: 720px; margin: 0 auto 8px; }
#vista-previa img { display: block; height: 72px; border-radius: 10px; }
#quitar-foto {
  position: absolute; top: -6px; right: -6px;
  width: 22px; height: 22px; border-radius: 50%; border: none;
  background: var(--texto); color: var(--fondo); font-size: 12px; cursor: pointer;
}

dialog {
  border: 1px solid var(--borde);
  border-radius: 14px;
  background: var(--superficie);
  color: var(--texto);
  width: min(320px, calc(100% - 32px));
}
dialog::backdrop { background: rgb(0 0 0 / .4); }
dialog form { display: flex; flex-direction: column; gap: 10px; }
dialog p { margin: 0; }
dialog input { padding: 10px; border: 1px solid var(--borde); border-radius: 8px; background: var(--fondo); color: var(--texto); font: inherit; }
dialog button { padding: 10px; border: none; border-radius: 8px; background: var(--acento); color: var(--acento-texto); font: inherit; cursor: pointer; }