body[data-page="chat"] {
  background-color: #0a0c11;
  background-image:
    radial-gradient(900px 600px at 15% 10%, rgba(255, 255, 255, 0.06), transparent 60%),
    radial-gradient(900px 700px at 85% 90%, rgba(255, 255, 255, 0.04), transparent 60%);
  overflow: hidden;
}

body[data-page="chat"] [data-chat-shell] {
  display: grid;
  grid-template-columns: minmax(240px, 320px) minmax(0, 1fr);
  grid-template-areas: "sidebar main";
  min-height: 100vh;
}

body[data-page="chat"] [data-chat-sidebar] {
  grid-area: sidebar;
  display: grid;
  grid-template-rows: auto auto 1fr;
  gap: 16px;
  padding: calc(20px + env(safe-area-inset-top)) 18px calc(18px + env(safe-area-inset-bottom));
  background: rgba(12, 14, 19, 0.96);
  box-shadow: 30px 0 60px rgba(0, 0, 0, 0.5);
  overflow: auto;
  animation: chat-enter 0.45s ease both;
}

body[data-page="chat"] [data-chat-sidebar-header] {
  display: grid;
  gap: 12px;
}

body[data-page="chat"] [data-chat-nav] {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

body[data-page="chat"] [data-chat-nav] a[data-button] {
  background: rgba(255, 255, 255, 0.06);
  font-size: 12px;
  padding: 6px 10px;
}

body[data-page="chat"] [data-chat-sidebar-actions] {
  display: flex;
  align-items: center;
  gap: 10px;
}

body[data-page="chat"] [data-chat-sidebar-body] {
  display: grid;
  gap: 14px;
  align-content: start;
}

body[data-page="chat"] [data-chat-panel] {
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.04);
  padding: 12px;
  display: grid;
  gap: 10px;
}

body[data-page="chat"] [data-chat-panel] > summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted-2);
}

body[data-page="chat"] [data-chat-panel] > summary::-webkit-details-marker {
  display: none;
}

body[data-page="chat"] [data-chat-panel] > summary::marker {
  content: "";
}

body[data-page="chat"] [data-chat-panel] > summary::after {
  content: "";
  width: 8px;
  height: 8px;
  border-right: 2px solid currentcolor;
  border-bottom: 2px solid currentcolor;
  transform: rotate(-45deg);
  transition: transform 150ms ease;
}

body[data-page="chat"] [data-chat-panel][open] > summary::after {
  transform: rotate(45deg);
}

body[data-page="chat"] [data-panel-body] {
  display: grid;
  gap: 12px;
}

body[data-page="chat"] [data-passkey-advanced],
body[data-page="chat"] [data-token-fallback] {
  display: grid;
  gap: 10px;
}

body[data-page="chat"] [data-passkey-advanced] summary,
body[data-page="chat"] [data-token-fallback] summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  list-style: none;
  color: var(--muted-2);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

body[data-page="chat"] [data-passkey-advanced] summary::-webkit-details-marker,
body[data-page="chat"] [data-token-fallback] summary::-webkit-details-marker {
  display: none;
}

body[data-page="chat"] [data-passkey-advanced] summary::marker,
body[data-page="chat"] [data-token-fallback] summary::marker {
  content: "";
}

body[data-page="chat"] [data-passkey-advanced] summary::after,
body[data-page="chat"] [data-token-fallback] summary::after {
  content: "";
  width: 8px;
  height: 8px;
  border-right: 2px solid currentcolor;
  border-bottom: 2px solid currentcolor;
  transform: rotate(-45deg);
  transition: transform 150ms ease;
}

body[data-page="chat"] [data-passkey-advanced][open] summary::after,
body[data-page="chat"] [data-token-fallback][open] summary::after {
  transform: rotate(45deg);
}

body[data-page="chat"] [data-passkey-advanced-body],
body[data-page="chat"] [data-token-fallback-body] {
  display: grid;
  gap: 12px;
  padding-top: 2px;
}

body[data-page="chat"] [data-chat-main] {
  grid-area: main;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 16px;
  min-height: 100vh;
  padding: calc(24px + env(safe-area-inset-top)) 32px calc(24px + env(safe-area-inset-bottom));
  animation: chat-enter 0.45s ease both;
  animation-delay: 60ms;
}

body[data-page="chat"] [data-chat-topbar] {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

body[data-page="chat"] h1 {
  font-size: clamp(22px, 2.4vw, 32px);
}

body[data-page="chat"] [data-chat-subtitle] {
  margin-top: 6px;
  color: var(--muted);
  font-size: 13px;
}

body[data-page="chat"] [data-messages] {
  min-height: 0;
  padding: 18px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.04);
  display: flex;
  flex-direction: column;
  gap: 16px;
  overflow: auto;
  box-shadow: var(--shadow-soft);
}

body[data-page="chat"] [data-messages]:empty {
  display: grid;
  place-items: center;
  color: var(--muted-2);
  font-size: 13px;
}

body[data-page="chat"] [data-messages]:empty::before {
  content: "Start a new chat.";
}

body[data-page="chat"] [data-message] {
  max-width: min(720px, 90%);
  padding: 12px 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.06);
  font-size: 14px;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-word;
  animation: chat-rise 0.25s ease both;
}

body[data-page="chat"] [data-message="user"] {
  align-self: flex-end;
  background: rgba(255, 255, 255, 0.12);
  border-radius: 16px 16px 6px 16px;
}

body[data-page="chat"] [data-message="assistant"] {
  align-self: flex-start;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 16px 16px 16px 6px;
}

body[data-page="chat"] [data-message="system"] {
  align-self: center;
  background: rgba(255, 255, 255, 0.02);
  color: var(--muted-2);
  font-size: 12px;
  text-align: center;
}

body[data-page="chat"] [data-message="error"] {
  align-self: center;
  background: rgba(246, 201, 201, 0.18);
  color: var(--danger);
}

body[data-page="chat"] [data-chat-form] {
  display: grid;
  gap: 10px;
}

body[data-page="chat"] [data-chat-compose] {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  padding: 12px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.06);
  box-shadow: var(--shadow-soft);
}

body[data-page="chat"] [data-chat-compose]:focus-within {
  box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.12), var(--shadow-soft);
}

body[data-page="chat"] [data-chat-compose-actions] {
  display: flex;
  align-items: flex-end;
  gap: 8px;
}

body[data-page="chat"] [data-chat-form] textarea {
  min-height: 60px;
  padding: 8px 10px;
  background: transparent;
  box-shadow: none;
}

body[data-page="chat"] [data-chat-form] textarea:focus {
  background: transparent;
  box-shadow: none;
}

body[data-page="chat"] button,
body[data-page="chat"] a[data-button] {
  border-radius: 12px;
  padding: 8px 12px;
  font-weight: 500;
}

body[data-page="chat"] button[data-icon-button] {
  width: 40px;
  height: 40px;
}

body[data-page="chat"] [data-chat-sidebar] input,
body[data-page="chat"] [data-chat-sidebar] textarea,
body[data-page="chat"] [data-chat-sidebar] select {
  background-color: rgba(255, 255, 255, 0.08);
}

@keyframes chat-rise {
  from {
    opacity: 0;
    transform: translateY(6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@media (max-width: 900px) {
  body[data-page="chat"] {
    overflow: auto;
  }

  body[data-page="chat"] [data-chat-shell] {
    grid-template-columns: 1fr;
    grid-template-areas:
      "main"
      "sidebar";
  }

  body[data-page="chat"] [data-chat-main] {
    min-height: auto;
    padding: calc(20px + env(safe-area-inset-top)) 16px 20px;
  }

  body[data-page="chat"] [data-chat-sidebar] {
    min-height: auto;
    padding: 20px 16px calc(24px + env(safe-area-inset-bottom));
    box-shadow: none;
  }

  body[data-page="chat"] [data-chat-topbar] {
    align-items: flex-start;
    flex-direction: column;
  }

  body[data-page="chat"] [data-chat-compose] {
    grid-template-columns: 1fr;
  }

  body[data-page="chat"] [data-chat-compose-actions] {
    justify-content: flex-end;
  }

  body[data-page="chat"] [data-chat-form] button {
    width: auto;
  }

  body[data-page="chat"] [data-chat-form] button[data-icon-button] {
    width: 40px;
    height: 40px;
  }

  body[data-page="chat"] [data-messages] {
    min-height: 50vh;
  }
}

@media (prefers-reduced-motion: reduce) {
  body[data-page="chat"] [data-message] {
    animation: none;
  }

  body[data-page="chat"] [data-chat-sidebar],
  body[data-page="chat"] [data-chat-main] {
    animation: none;
  }

  body[data-page="chat"] [data-chat-panel] > summary::after,
  body[data-page="chat"] [data-passkey-advanced] summary::after,
  body[data-page="chat"] [data-token-fallback] summary::after {
    transition: none;
  }
}