@layer components {
  /* ============================================================
     Chat -- Conversation interface for Brain Dump
     ============================================================ */

  .chat {
    display: flex;
    flex-direction: column;
    block-size: 100%;
    max-block-size: calc(100dvh - var(--nav-height) - var(--tab-bar-height));
    overflow: hidden;
  }

  @media (min-width: 800px) {
    .chat {
      max-block-size: calc(100dvh - var(--nav-height));
    }
  }

  /* Header */
  .chat__header {
    display: flex;
    align-items: center;
    gap: var(--inline-space);
    padding: var(--block-space-half) var(--inline-space);
    border-block-end: var(--border);
    flex-shrink: 0;
  }

  .chat__back {
    display: inline-flex;
    color: var(--color-ink-secondary);
    text-decoration: none;
  }

  .chat__back:hover {
    color: var(--color-link);
  }

  .chat__header-info {
    display: flex;
    flex-direction: column;
    min-inline-size: 0;
  }

  .chat__title {
    font-weight: 600;
    font-size: var(--text-normal);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .chat__purpose {
    font-size: var(--text-small);
    color: var(--color-ink-muted);
  }

  /* Messages area */
  .chat__messages {
    flex: 1;
    overflow-y: auto;
    padding: var(--block-space) var(--inline-space);
    display: flex;
    flex-direction: column;
    gap: var(--block-space);
    overscroll-behavior: contain;
  }

  /* Individual message */
  .chat__message {
    max-inline-size: 85%;
    padding: var(--block-space-half) var(--inline-space);
    border-radius: var(--radius-lg);
    line-height: var(--line-height);
    word-break: break-word;
  }

  .chat__message--user {
    align-self: flex-end;
    background-color: var(--color-link);
    color: oklch(var(--lch-canvas));
  }

  .chat__message--assistant {
    align-self: flex-start;
    background-color: var(--color-surface);
    border: var(--border);
  }

  .chat__message--system {
    align-self: center;
    font-size: var(--text-small);
    color: var(--color-ink-muted);
    font-style: italic;
  }

  .chat__message-content {
    white-space: pre-wrap;
  }

  .chat__message-content span {
    display: inline;
  }

  .chat__message-meta {
    display: block;
    font-size: var(--text-xs);
    color: var(--color-ink-muted);
    margin-block-start: 0.25rem;
    opacity: 0.7;
  }

  /* Streaming message */
  .chat__message--streaming .chat__message-content:empty + .chat__typing-indicator {
    display: flex;
  }

  .chat__message--streaming .chat__message-content:not(:empty) + .chat__typing-indicator {
    display: none;
  }

  /* Typing indicator */
  .chat__typing-indicator {
    display: flex;
    gap: 0.25rem;
    padding: 0.25rem 0;
  }

  .chat__typing-indicator span {
    display: block;
    inline-size: 0.5rem;
    block-size: 0.5rem;
    border-radius: 50%;
    background-color: var(--color-ink-muted);
    animation: chat-typing 1.4s infinite ease-in-out both;
  }

  .chat__typing-indicator span:nth-child(1) { animation-delay: 0s; }
  .chat__typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
  .chat__typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

  @keyframes chat-typing {
    0%, 80%, 100% { opacity: 0.3; transform: scale(0.8); }
    40% { opacity: 1; transform: scale(1); }
  }

  /* Error banner */
  .chat__error {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--inline-space);
    padding: var(--block-space-half) var(--inline-space);
    background-color: oklch(var(--lch-negative) / 0.1);
    color: var(--color-negative);
    font-size: var(--text-small);
    flex-shrink: 0;
  }

  .chat__error[hidden] {
    display: none;
  }

  .chat__error-dismiss {
    background: none;
    border: none;
    color: inherit;
    cursor: pointer;
    font-size: var(--text-small);
    text-decoration: underline;
    padding: 0;
  }

  /* Input area */
  .chat__input-area {
    padding: var(--block-space-half) var(--inline-space);
    padding-block-end: calc(var(--block-space-half) + var(--safe-inset-bottom));
    border-block-start: var(--border);
    background-color: var(--color-canvas);
    flex-shrink: 0;
  }

  .chat__form {
    display: flex;
    align-items: flex-end;
    gap: var(--inline-space-half);
  }

  .chat__input {
    flex: 1;
    resize: none;
    border: var(--border);
    border-radius: var(--radius-lg);
    padding: var(--block-space-half) var(--inline-space);
    font-family: var(--font-sans);
    font-size: var(--text-normal);
    line-height: var(--line-height);
    max-block-size: 8rem;
    overflow-y: auto;
    background-color: var(--color-canvas);
    color: var(--color-ink);
  }

  .chat__input:focus {
    outline: var(--focus-ring);
    outline-offset: var(--focus-ring-offset);
  }

  .chat__send {
    flex-shrink: 0;
  }

  .chat__send:disabled {
    opacity: 0.5;
    cursor: not-allowed;
  }

  /* Conversation list */
  .chat-list {
    padding: var(--block-space) var(--inline-space);
    max-inline-size: var(--editor-max-width);
    margin-inline: auto;
  }

  .chat-list__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-block-end: var(--block-space);
  }

  .chat-list__title {
    font-size: var(--text-large);
    font-weight: 600;
  }

  .chat-list__items {
    display: flex;
    flex-direction: column;
    gap: var(--block-space-half);
  }

  .chat-list__item {
    display: flex;
    flex-direction: column;
    padding: var(--block-space) var(--inline-space);
    border: var(--border);
    border-radius: var(--radius);
    text-decoration: none;
    color: var(--color-ink);
    transition: border-color var(--transition-fast);
  }

  .chat-list__item:hover {
    border-color: var(--color-link);
  }

  .chat-list__item-title {
    font-weight: 600;
  }

  .chat-list__item-meta {
    font-size: var(--text-small);
    color: var(--color-ink-muted);
    margin-block-start: 0.25rem;
  }

  /* New conversation form */
  .chat-new {
    padding: var(--block-space) var(--inline-space);
    max-inline-size: var(--editor-max-width);
    margin-inline: auto;
  }

  .chat-new__title {
    font-size: var(--text-large);
    font-weight: 600;
    margin-block-end: var(--block-space-half);
  }

  .chat-new__description {
    color: var(--color-ink-secondary);
    margin-block-end: var(--block-space);
  }

  .chat-new__form {
    display: flex;
    flex-direction: column;
    gap: var(--block-space);
  }

  .chat-new__purposes {
    border: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: var(--block-space-half);
  }

  .chat-new__purpose-option {
    display: grid;
    grid-template-columns: auto 1fr;
    grid-template-rows: auto auto;
    gap: 0 var(--inline-space-half);
    padding: var(--block-space-half) var(--inline-space);
    border: var(--border);
    border-radius: var(--radius);
    cursor: pointer;
    transition: border-color var(--transition-fast);
  }

  .chat-new__purpose-option:has(input:checked) {
    border-color: var(--color-link);
    background-color: oklch(var(--lch-link) / 0.05);
  }

  .chat-new__purpose-option input[type="radio"] {
    grid-row: 1 / -1;
    align-self: center;
  }

  .chat-new__purpose-label {
    font-weight: 600;
  }

  .chat-new__purpose-description {
    grid-column: 2;
    font-size: var(--text-small);
    color: var(--color-ink-secondary);
  }

  .chat-new__actions {
    display: flex;
    gap: var(--inline-space);
  }
}