:root {
  --radius: 18px;
  --transition: 0.3s ease;
  --max-width: 700px;
}

/* Modo oscuro */
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111;
    --text: #f5f5f5;
    --accent: #2a2a2a;
    --input-bg: #222;
    --bubble-user: #333;
    --input-field: #1a1a1a;
    --shadow: rgba(0, 0, 0, 0.3);
    --disclaimer: #999;
  }
}

/* Modo claro */
@media (prefers-color-scheme: light) {
  :root {
    --bg: #f7f7f7;
    --text: #111;
    --accent: #ddd;
    --input-bg: #fff;
    --bubble-user: #efefef;
    --input-field: #ffffff;
    --shadow: rgba(0, 0, 0, 0.08);
    --disclaimer: #888;
  }
}

body {
  font-family: "Inter", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  transition: background var(--transition), color var(--transition);
}

/* Cabecera con blur sutil y mismo tono que el fondo */
header {
  width: 100%;
  max-width: var(--max-width);
  position: sticky;
  top: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  background-color: rgba(255, 255, 255, 0.02); /* casi transparente, mismo tono */
  padding: 8px 0;
  box-sizing: border-box;
  z-index: 10;
  border: none; /* sin línea de separación */
}

@media (prefers-color-scheme: dark) {
  header {
    background-color: rgba(17, 17, 17, 0.02);
  }
}

/* Logo Eli centrado */
.eli-logo {
  height: 20px;
  opacity: 0.9;
  user-select: none;
  -webkit-user-drag: none;
}

/* Chat */
.chat-container {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  width: 100%;
  max-width: var(--max-width);
  padding: 0 20px;
  box-sizing: border-box;
}

.messages {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px 0;
  box-sizing: border-box;
}

.message {
  padding: 12px 16px;
  border-radius: var(--radius);
  max-width: 80%;
  line-height: 1.4;
  word-wrap: break-word;
  transition: background var(--transition);
}

.user {
  background: var(--bubble-user);
  align-self: flex-end;
  border-bottom-right-radius: 4px;
}

.bot {
  background: var(--input-bg);
  align-self: flex-start;
  border-bottom-left-radius: 4px;
}

/* Input */
.input-container {
  width: 100%;
  max-width: var(--max-width);
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 12px 14px;
  background: none;
  position: sticky;
  bottom: 0;
  box-sizing: border-box;
}

.input-wrapper {
  display: flex;
  align-items: center;
  gap: 8px;
}

input {
  flex: 1;
  border: none;
  outline: none;
  background: var(--input-field);
  color: var(--text);
  font-size: 16px;
  padding: 12px 18px;
  border-radius: 50px;
  box-shadow: 0 2px 8px var(--shadow);
}

input::placeholder {
  color: #888;
}

button {
  background: var(--text);
  color: var(--bg);
  border: none;
  border-radius: 50%;
  width: 42px;
  height: 42px;
  cursor: pointer;
  transition: background var(--transition), transform 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

button svg {
  width: 18px;
  height: 18px;
}

button:hover {
  opacity: 0.85;
  transform: scale(1.05);
}

/* Disclaimer */
.disclaimer {
  font-size: 11px;
  color: var(--disclaimer);
  text-align: center;
  margin: 0;
  line-height: 1.2;
  opacity: 0.7;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 6px;
}
::-webkit-scrollbar-thumb {
  background: var(--accent);
  border-radius: 3px;
}