/*
 * static/css/chat.css — bubbles, work chips and their animations, refusal marker, turn-end note, composer, recovery bar, attachment tray, jump button, code-copy island.
 *
 * Owner: WP A-15. Spec: FA §8, §16.1 (no visual change: values are the legacy index.html values
 * after its later "VISUAL REDESIGN INTEGRATION" overrides, merged into one rule each).
 * Every selector is defined once, in one file (I7; T-CSS checks the critical ones).
 * Also here (nothing else owns them): the chat column (#chat-box), the welcome state, chat
 * markdown (.markdown-content), citation chips (.cite-chip) and in-timeline notices.
 * Tokens come from tokens.css; the assistant avatar is the fork seam --assistant-avatar
 * (default: the profile portrait served at /brand/portrait.png).
 */

/* ============================================================
   CHAT COLUMN
   ============================================================ */
#chat-box {
    flex: 1;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    scroll-behavior: auto;
    z-index: 2;
    position: relative;
    overflow-x: hidden;   /* guard: nothing may make the chat pane scroll sideways (wide content scrolls in its own box) */
    padding: 100px 34px var(--chat-bottom-padding, max(154px, calc(var(--composer-clearance, 142px) + 12px)));
    /* The scrollport runs under the glass nav and the composer: keyboard focus scrolls a control out
       from under both (V-6 Z35). --composer-clearance is the live composer height (recovery bar and
       tray included), so this also tracks the expanded composer. */
    scroll-padding: 100px 0 calc(var(--composer-clearance, 142px) + 12px);
    gap: 30px;
    background: transparent;
    overscroll-behavior: contain;
    transition: background-color .25s ease, color .25s ease, border-color .25s ease;
}
#chat-box:has(.welcome-message) {
    padding-top: 86px;
    padding-bottom: var(--welcome-bottom-padding, 132px);
    overflow-y: hidden;
    overscroll-behavior: none;
    justify-content: center;
}
body.composer-expanded #chat-box { --chat-bottom-padding: calc(var(--composer-clearance, 154px) + 42px); }
body.composer-expanded #chat-box:has(.welcome-message) {
    --welcome-bottom-padding: calc(var(--composer-clearance, 132px) + 42px);
    overflow-y: auto;
    overscroll-behavior: contain;
    justify-content: flex-start;
}
#chat-box:has(.welcome-message) .welcome-message { margin-top: auto; margin-bottom: auto; transform: translateY(48px); }
body.composer-expanded #chat-box:has(.welcome-message) .welcome-message { margin-top: 0; margin-bottom: 0; }
#chat-box:not(:has(.welcome-message)) > .message:first-child { margin-top: auto; }
#chat-box:not(:has(.welcome-message)) > .message:last-of-type { margin-bottom: 10px; }
.drag-over #chat-box,
.drag-over #input-area { outline: 2px dashed var(--gold-accent); outline-offset: -8px; background: var(--drag-tint); }

/* Jump-to-latest button. The #main-area prefix out-ranks the `#main-area > *` positioning rule
   (layout.css); without it the button sat in normal flow under #chat-box and took no clicks (I7). */
#main-area > .jump-bottom-btn {
    display: none;
    position: absolute;
    left: 50%;
    bottom: calc(var(--composer-clearance, 104px) + 12px);
    transform: translateX(-50%);
    width: 40px;
    height: 40px;
    border-radius: var(--radius-pill);
    border: 1px solid var(--border-color);
    background: var(--card-bg);
    color: var(--gold-accent);
    cursor: pointer;
    z-index: 25; /* above #chat-box (2) and #input-area (20); below the nav (30), the files pane, the stage, the lightbox and the mobile sidebar */
    pointer-events: auto;
    align-items: center;
    justify-content: center;
    font-size: 1.15rem;
    box-shadow: var(--elev-2);
    transition: background 0.15s, transform 0.15s;
}
#main-area > .jump-bottom-btn.active { display: flex; }
#main-area > .jump-bottom-btn:hover { background: var(--border-color); transform: translateX(-50%) translateY(-2px); }
body.home-mode #jump-bottom-btn,
body.auth-mode #jump-bottom-btn,
#chat-box:has(.welcome-message) + #jump-bottom-btn { display: none !important; }

/* ============================================================
   WELCOME STATE (FA §16.3; copy from /brand/site.json)
   ============================================================ */
.welcome-message {
    position: relative;
    z-index: 1;
    width: min(900px, 100%);
    max-width: 900px;
    margin: auto;
    padding: 24px 16px 34px;
    text-align: left;
    color: var(--text-color);
    display: block !important;
    grid-column: 1 / -1;
}
.welcome-message h1 { margin-top: 16px; margin-bottom: 10px; font-size: clamp(2.7rem, 5vw, 4.7rem); line-height: 0.98; letter-spacing: -0.055em; overflow-wrap: anywhere; } /* a long username wraps instead of being clipped (X37) */
.welcome-message h2 { max-width: 680px; margin: 16px 0 10px; color: var(--text-dim); font-size: 1.22rem; font-weight: 500; }
.welcome-message > p { max-width: 800px; color: var(--text-dim); font-size: 0.98rem; line-height: 1.65; }
.welcome-kicker {
    display: block;
    color: var(--gold-accent);
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.13em;
    text-transform: uppercase;
}
.starter-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; margin-top: 28px; }
.starter-grid button {
    min-height: 108px;
    padding: 18px;
    text-align: left;
    border: 1px solid var(--border-color);
    border-radius: 18px;
    background: color-mix(in srgb, var(--surface-2) 88%, transparent);
    color: var(--text-color);
    cursor: pointer;
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    transition: transform 0.16s, border-color 0.16s, background 0.16s;
}
.starter-grid button:hover { transform: translateY(-2px); border-color: var(--gold-glow); background: var(--card-bg); }
.starter-grid span { display: block; font-weight: 650; }
.starter-grid small { display: block; margin-top: 8px; color: var(--text-muted); line-height: 1.45; }

/* ============================================================
   MESSAGES (bubbles)
   Assistant: avatar grid. User: gold-tinted right-aligned card, no avatar.
   ============================================================ */
.message {
    max-width: 900px;
    margin: 0 auto;
    width: 100%;
    line-height: 1.7;
    display: grid;
    grid-template-columns: 38px minmax(0, 1fr);
    column-gap: 16px;
    align-items: start;
    animation: message-in 0.3s ease both;
}
@keyframes message-in { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: translateY(0); } }
.message > * { grid-column: 2; min-width: 0; }
.message::before {
    content: '';
    grid-column: 1;
    grid-row: 1 / span 1;
    width: 38px;
    height: 38px;
    border-radius: 50%;
    background-size: cover;
    background-position: center;
    margin-top: 2px;
    flex-shrink: 0;
}
.message:has(.user-label) { grid-template-columns: 1fr; }
.message:has(.user-label) > * { grid-column: 1; }
.message:has(.user-label)::before { content: none; display: none; }
.message:has(.ai-label)::before {
    background-image: var(--assistant-avatar, url('/brand/portrait.png'));
    background-size: cover;
    background-position: center;
    background-color: transparent;
    border: 2px solid var(--gold-accent);
    box-shadow: 0 0 0 3px var(--gold-soft);
}
.message:has(.user-label) .message-body {
    background: var(--gold-soft);
    border: 1px solid var(--gold-glow);
    border-radius: 20px 20px 7px 20px;
    padding: 13px 16px;
    max-width: 72%;
    margin-left: auto;
}
.user-label, .ai-label { font-size: 0.7rem; font-weight: 600; letter-spacing: 0.09em; margin-bottom: 10px; text-transform: uppercase; }
.user-label { color: var(--text-color); text-align: right; }
.ai-label { color: var(--gold-accent); }

/* A steer (R-85) waiting for the step boundary: dimmed until steer.applied moves it into place. */
.message.steer-queued { opacity: 0.55; }
.steer-queued-note { margin-top: var(--space-2); color: var(--meta-text); font-size: 0.76rem; text-align: right; }

/* Per-message timestamp (PA-8), viewer's zone; full date/zone/offset in the title. */
.message-time { color: var(--meta-text); font-size: 0.72rem; font-variant-numeric: tabular-nums; }
/* G2 (B-14 CCR): the stamp sits inside the uppercase label */
.ai-label .message-time, .user-label .message-time { margin-left: 8px; text-transform: none; letter-spacing: normal; font-weight: 400; }

.message-actions {
    display: flex;
    align-items: center;
    gap: 6px;
    min-height: 26px;
    margin-top: 14px;
    padding-bottom: 8px;
    color: var(--meta-text);
    font-size: 0.78rem;
    opacity: 0;
    transition: opacity 0.15s;
}
.message:has(.user-label) .message-actions { justify-self: end; justify-content: flex-end; max-width: 80%; margin-left: auto; }
.message:hover .message-actions,
.message:focus-within .message-actions { opacity: 1; }
.message-action-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 26px;
    min-height: 24px;
    border: 1px solid transparent;
    background: transparent;
    color: var(--text-muted);
    border-radius: var(--radius-sm);
    padding: 3px 8px;
    cursor: pointer;
    line-height: 1.2;
    font-family: inherit;
    font-size: 0.78rem;
    transition: background 0.15s, color 0.15s;
}
.message-action-btn svg { display: block; }
.message-action-btn:hover:not(:disabled) { color: var(--gold-accent); background: var(--card-bg); }
.message-action-btn:disabled { opacity: 0.4; cursor: not-allowed; }
.variant-count { color: var(--meta-text); min-width: 34px; text-align: center; font-variant-numeric: tabular-nums; }

/* In-place editing: the bubble itself becomes the editor (full row, seamless textarea). */
.message.editing .message-body,
.message.editing:has(.user-label) .message-body { max-width: 100%; width: 100%; border-color: var(--gold-accent); box-shadow: var(--ring); }
.message-edit-box {
    display: block;
    width: 100%;
    padding: 0;
    background: transparent;
    border: none;
    color: var(--text-color);
    resize: none;
    font-family: inherit;
    font-size: inherit;
    line-height: 1.7;
    min-height: 1.7em;
    outline: none;
    overflow: hidden;
}
.message-edit-box:focus-visible { outline: none; }
.message-edit-actions { display: flex; gap: var(--space-2); margin-top: var(--space-3); justify-content: flex-end; }
.message-edit-actions .edit-action-pill { min-width: 74px; }

/* Attachments on a sent user message */
.message-attachments { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-2); }
.message-attachment {
    border: 1px solid var(--border-color);
    background: var(--card-bg);
    color: var(--link-text);
    border-radius: var(--radius-sm);
    padding: 5px 8px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: background 0.15s;
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    max-width: 100%;
}
.message-attachment-name { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.message-attachment:hover { background: var(--border-color); }

/* ============================================================
   TURN TIMELINE (FA §8): text, work runs, displays, controls, notices in block order
   ============================================================ */
.turn-timeline { display: flex; flex-direction: column; gap: 10px; min-width: 0; }
.turn-timeline > .markdown-content { min-width: 0; }

/* Work runs and steps (FA §8.3, R-18). Not interactive: no toggles, no pointer affordance (B3). */
.work-run { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.work-step { cursor: default; user-select: none; min-width: 0; overflow-wrap: anywhere; }
.think-chip {
    padding: 8px 13px;
    font-size: 0.82rem;
    font-weight: 500;
    background: color-mix(in srgb, var(--think-bg) 84%, transparent);
    border: 1px solid var(--think-border);
    border-radius: 15px;
    color: var(--think-text);
}
.tool-chip {
    padding: 9px 12px;
    font-size: 0.85rem;
    font-family: var(--font-mono);
    color: var(--indicator-text);
    background: var(--code-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: opacity 0.15s;
}
/* UX-5: the chip appears on the first tool_use fragment; while the call is still being written it is
   slightly dimmed. Only its border and spinner dim: the label keeps full contrast (WCAG AA). */
.tool-chip[data-state="authoring"] { border-color: color-mix(in srgb, var(--border-color) 50%, transparent); }
.tool-chip[data-state="authoring"] .tool-inline-spinner { opacity: 0.6; }
.tool-chip[data-state="error"] .tool-chip-label { color: var(--danger-text); }
.tool-chip[data-state="stopped"] .tool-chip-label { color: var(--text-muted); }
.folded-chip {
    padding: 6px 12px;
    font-size: 0.8rem;
    color: var(--meta-text);
    border: 1px dashed var(--border-color);
    border-radius: var(--radius-md);
}
/* Inline spinner in a running tool chip, so a long call never looks like a hang. */
.tool-inline-spinner {
    display: inline-block;
    width: 11px;
    height: 11px;
    border: 2px solid var(--spinner-track);
    border-top-color: var(--gold-accent);
    border-radius: 50%;
    animation: chat-spin 0.8s linear infinite;
    vertical-align: -1px;
    margin-right: 6px;
}
.thinking-dots { display: inline-block; width: 1.35em; text-align: left; }
.think-chip[data-state="running"] .thinking-dots::after { content: ''; animation: thinking-dots 1.15s steps(1, end) infinite; }
@keyframes thinking-dots {
    0%, 100% { content: ''; }
    25% { content: '.'; }
    50% { content: '..'; }
    75% { content: '...'; }
}
/* Tail liveness (UX-4): replaces the legacy .tool-loading "Working..." box. */
.work-pending {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    width: fit-content;
    padding: 8px 12px;
    font-size: 0.85rem;
    font-family: var(--font-mono);
    color: var(--gold-accent);
    background: var(--gold-soft);
    border: 1px solid var(--gold-glow);
    border-radius: var(--radius-md);
    cursor: default;
}
.work-pending .spinner {
    width: 15px;
    height: 15px;
    border: 2px solid var(--spinner-track);
    border-radius: 50%;
    border-top-color: var(--gold-accent);
    animation: chat-spin 0.8s linear infinite;
}
@keyframes chat-spin { to { transform: rotate(360deg); } }

/* In-timeline notices (notice blocks, e.g. upstream retrying, usage limit) */
.timeline-notice {
    padding: 8px 12px;
    font-size: 0.85rem;
    line-height: 1.5;
    color: var(--warning-text);
    background: var(--warning-bg);
    border: 1px solid var(--warning-border);
    border-radius: var(--radius-md);
}
.timeline-notice[data-level="info"] { color: var(--indicator-text); background: var(--gold-soft); border-color: var(--gold-glow); }

/* Inline turn-end line inside the bubble (FA §12.2: stopped / interrupted / error) */
.turn-end-note { margin-top: var(--space-2); color: var(--meta-text); font-size: 0.82rem; font-style: italic; }
.turn-end-note[data-status="error"] { color: var(--danger-text); font-style: normal; }

/* Refused reply (A5): partial output is gone; a muted marker stands in its place. */
.refusal-marker {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: 8px 12px;
    color: var(--text-muted);
    font-size: 0.88rem;
    font-style: italic;
    background: var(--card-bg);
    border: 1px dashed var(--border-strong);
    border-radius: var(--radius-md);
}
.refusal-marker .edit-action-pill {
    font: inherit;
    font-style: normal;
    font-size: 0.85rem;
    padding: 4px 12px;
    white-space: nowrap;
    color: var(--text-muted);
    background: var(--surface-1);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-pill);
    cursor: pointer;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.refusal-marker .edit-action-pill:hover { background: var(--card-bg); color: var(--gold-accent); border-color: var(--border-strong); }

/* ============================================================
   CHAT MARKDOWN (render/markdown.js output)
   ============================================================ */
/* Long unbroken tokens (bare URLs, log lines) wrap instead of widening the column. Tables keep
   normal wrapping and scroll inside their own box; pre and math scroll too (white-space). */
.markdown-content { overflow-wrap: anywhere; }
.markdown-content p { margin-bottom: var(--space-3); }
.markdown-content > :first-child { margin-top: 0; }
.markdown-content > :last-child { margin-bottom: 0; }
.markdown-content h1, .markdown-content h2, .markdown-content h3, .markdown-content h4 { margin: var(--space-5) 0 var(--space-3); line-height: 1.3; font-weight: 600; }
.markdown-content h1 { font-size: 1.5rem; }
.markdown-content h2 { font-size: 1.3rem; }
.markdown-content h3 { font-size: 1.12rem; }
.markdown-content h4 { font-size: 1rem; }
.markdown-content a { color: var(--link-text); text-decoration: none; border-bottom: 1px solid var(--gold-glow); transition: border-color 0.15s; }
.markdown-content a:hover { border-bottom-color: var(--gold-accent); }
.markdown-content strong { font-weight: 600; color: var(--text-color); }
.markdown-content hr { border: none; border-top: 1px solid var(--border-color); margin: var(--space-5) 0; }
.markdown-content blockquote { margin: var(--space-3) 0; padding: var(--space-1) var(--space-4); border-left: 3px solid var(--gold-accent); color: var(--text-dim); background: var(--gold-soft); border-radius: 0 var(--radius-sm) var(--radius-sm) 0; }
.markdown-content table { border-collapse: collapse; margin: var(--space-3) 0; width: 100%; font-size: 0.92em; display: block; overflow-x: auto; }
.markdown-content th, .markdown-content td { border: 1px solid var(--border-color); padding: 8px 12px; text-align: left; overflow-wrap: normal; }
.markdown-content th { background: var(--card-bg); font-weight: 600; }
.markdown-content tr:nth-child(even) td { background: var(--gold-soft); }
.markdown-content ul, .markdown-content ol { margin: var(--space-2) 0 var(--space-4); padding-left: 1.5rem; list-style-position: outside; }
.markdown-content li { margin: 4px 0; padding-left: 0.15rem; overflow-wrap: anywhere; }
.markdown-content li::marker { color: var(--gold-accent); }
.markdown-content li > p { display: inline; margin: 0; }
.markdown-content li > p + p { display: block; margin-top: var(--space-2); }
.markdown-content img { max-width: 100%; height: auto; border-radius: var(--radius-sm); }
.markdown-content .aiw-chat-image { display: block; max-height: 480px; margin: var(--space-3) 0; cursor: zoom-in; border: 1px solid var(--border-color); }
.markdown-content .aiw-image-missing { color: var(--text-muted); font-style: italic; }
.markdown-content .aiw-workspace-link { font-family: var(--font-mono); font-size: 0.92em; }
.markdown-content .aiw-math-pending { font-family: var(--font-mono); font-size: 0.92em; color: var(--text-muted); }
.markdown-content .aiw-math-error { font-family: var(--font-mono); font-size: 0.92em; color: var(--danger-text); }
.markdown-content div.aiw-math { margin: var(--space-3) 0; overflow-x: auto; overflow-y: hidden; }
.markdown-content .preserved-blank-line { height: 1.2em; }
.markdown-content pre { background: var(--code-bg); padding: var(--space-4); border-radius: var(--radius-md); overflow-x: auto; margin: var(--space-3) 0; border: 1px solid var(--border-color); font-family: var(--font-mono); font-size: 0.85rem; line-height: 1.55; }
.markdown-content code { font-family: var(--font-mono); }
/* one box per code block (X38): the highlight.js theme's own box (background, padding, scroller) is
   dropped inside the tuned pre, so highlighted and plain blocks match; the token colours stay */
.markdown-content pre code.hljs { padding: 0; background: transparent; overflow: visible; }
.markdown-content :not(pre) > code { display: inline; background: var(--code-bg); border: 1px solid var(--border-color); color: var(--code-inline-text); border-radius: var(--radius-sm); padding: 0.08em 0.34em; font-size: 0.88em; overflow-wrap: anywhere; }
.markdown-content .katex-display { overflow-x: auto; overflow-y: hidden; padding: 2px 0; }

/* Code-copy island: the button is itself sticky, so it stays inside the code box (top or
   bottom). --code-copy-sticky-top is set in JS to the nav's bottom edge minus the chat
   padding; never hard-code it. The code is pulled up under the button's flow height. */
.code-block-wrapper { position: relative; margin: var(--space-3) 0; display: flex; flex-direction: column; }
.code-block-wrapper pre { margin: -38px 0 0 0; }
.copy-code-btn {
    position: sticky;
    top: var(--code-copy-sticky-top, 12px);
    align-self: flex-end;
    z-index: 6;
    margin: 8px 8px 0 8px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 30px;
    height: 30px;
    background: color-mix(in srgb, var(--code-bg) 82%, transparent);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    border-radius: var(--radius-md);
    cursor: pointer;
    opacity: 0.6;
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.18);
    transition: opacity 0.15s, color 0.15s, background 0.15s, border-color 0.15s;
}
.code-block-wrapper:hover .copy-code-btn { opacity: 1; }
.copy-code-btn:hover { color: var(--gold-accent); border-color: var(--border-strong); background: var(--code-bg); }
.copy-code-btn.copied { color: var(--gold-accent); opacity: 1; }
.copy-code-btn svg { display: block; }

/* Citation chips: favicon + per-message number ([cite:N], R-01) */
.cite-chip {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    height: 17px;
    padding: 0 6px;
    margin: 0 3px;
    border-radius: var(--radius-pill);
    font-size: 0.68rem;
    line-height: 1;
    vertical-align: text-top;
    text-decoration: none;
    background: var(--gold-soft);
    border: 1px solid var(--gold-glow);
    color: var(--link-text);
    font-family: var(--font-mono);
    transition: background 0.15s, border-color 0.15s;
}
.cite-chip:hover { background: var(--gold-glow); border-color: var(--gold-accent); }
.cite-favicon { width: 11px; height: 11px; border-radius: 3px; flex: none; }
.cite-number { font-weight: 600; }

/* ============================================================
   RECOVERY BAR (above the composer: Continue / Rerun after an interrupted turn)
   ============================================================ */
.recovery-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-3);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-lg);
    background: var(--surface-2);
    padding: 8px 14px;
    box-shadow: var(--elev-1);
}
.recovery-text { color: var(--indicator-text); font-size: 0.88rem; }
.recovery-actions { display: flex; gap: var(--space-2); }
.recovery-btn { font-size: 0.85rem; padding: 5px 14px; }

/* ============================================================
   COMPOSER
   ============================================================ */
#input-area {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 20;
    display: flex;
    justify-content: center;
    padding: 28px 28px 22px;
    background: linear-gradient(to top, color-mix(in srgb, var(--chat-bg) 96%, transparent) 30%, transparent 100%);
    pointer-events: none;
    transition: background-color .25s ease, color .25s ease, border-color .25s ease;
}
/* minmax(0, 1fr): an auto track grows to the min-content of a long nowrap file name and pushes
   Send off a 375 px screen; a zero minimum lets the pill's max-width and the name's ellipsis work. */
.input-stack { max-width: 900px; width: 100%; display: grid; grid-template-columns: minmax(0, 1fr); gap: var(--space-2); pointer-events: auto; }
.composer-card {
    display: block;
    padding: 7px;
    border: 1px solid color-mix(in srgb, var(--border-strong) 88%, transparent);
    border-radius: var(--radius-pill);
    background: color-mix(in srgb, var(--surface-2) 78%, transparent);
    box-shadow: 0 16px 46px rgba(0, 0, 0, 0.28);
    backdrop-filter: blur(24px) saturate(1.14);
    -webkit-backdrop-filter: blur(24px) saturate(1.14);
    transition: border-color 0.18s, box-shadow 0.18s;
}
.composer-card:focus-within { border-color: var(--gold-accent); box-shadow: var(--elev-2), var(--ring); }
.composer-card.is-multiline { border-radius: 25px; }
.composer-main-row { display: flex; align-items: center; gap: 8px; min-height: 50px; }
.composer-card.is-multiline .composer-main-row { align-items: flex-end; }
.composer-add-btn {
    width: 42px;
    height: 42px;
    flex: 0 0 42px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    border: 0;
    border-radius: var(--radius-pill);
    color: var(--text-dim);
    background: transparent;
    font-family: inherit;
    font-size: 1.72rem;
    font-weight: 300;
    line-height: 1;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
}
.composer-add-btn:hover { color: var(--gold-accent); background: var(--gold-soft); }
.input-wrapper { flex: 1; min-width: 0; width: 100%; display: flex; gap: var(--space-2); align-items: center; }
#prompt-input {
    flex: 1;
    min-width: 0;   /* WebKit keeps a textarea's intrinsic width (~191px) and pushes Send off a 375px row */
    width: 100%;
    min-height: 42px;
    max-height: 176px;
    height: 42px;
    padding: 10px 4px;
    background: transparent;
    border: none;
    color: var(--text-color);
    border-radius: var(--radius-md);
    resize: none;
    font-family: inherit;
    font-size: 1rem;
    line-height: 1.45;
    overflow-y: auto;
    outline: none;
}
#prompt-input::placeholder { color: var(--text-faint); }
#send-btn {
    width: 42px;
    height: 42px;
    min-width: 42px;
    padding: 0;
    border: none;
    border-radius: var(--radius-pill);
    background-color: var(--gold-accent);
    color: var(--gold-on);
    font-family: inherit;
    font-weight: 600;
    font-size: 1.25rem;
    line-height: 1;
    cursor: pointer;
    box-shadow: 0 8px 22px var(--gold-glow);
    transition: background 0.2s, transform 0.1s, box-shadow 0.2s;
}
#send-btn:hover { background-color: var(--gold-accent-hover); box-shadow: 0 6px 18px var(--gold-glow); }
#send-btn:active { transform: translateY(1px); }
#send-btn:disabled { background-color: var(--muted-control); color: var(--text-muted); cursor: not-allowed; box-shadow: none; }
/* Stop sits next to Send while a turn runs (R-85: the composer stays enabled for steers). */
.stop-btn { display: none; height: 42px; min-width: 40px; padding: 0 16px; border-radius: var(--radius-pill); font-size: 0.92rem; }
.stop-btn.active { display: inline-flex; align-items: center; justify-content: center; }

/* Attachment tray, upload progress, file pills */
.upload-progress { display: none; border: 1px solid var(--border-color); background: var(--card-bg); border-radius: var(--radius-md); padding: 8px 10px; color: var(--indicator-text); font-size: 0.85rem; }
.upload-progress.active { display: block; }
.attachment-tray { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.attachment-tray:empty { display: none; }
.attachment-tray:not(:empty) { padding: 5px 8px 8px; }
.file-pill {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    max-width: 100%;
    border: 1px solid var(--gold-glow);
    background: var(--gold-soft);
    color: var(--link-text);
    border-radius: var(--radius-pill);
    padding: 4px 10px 4px 6px;
    font-size: 0.82rem;
    transition: background 0.15s;
}
.file-pill.previewable { cursor: pointer; }
.file-pill.previewable:hover { background: var(--gold-glow); }
.file-pill-name { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-pill-token { font-size: 0.7rem; color: var(--file-pill-token); white-space: nowrap; }
.file-pill button { border: none; background: transparent; color: var(--text-muted); cursor: pointer; border-radius: 50%; padding: 0 4px; font-size: 0.95rem; line-height: 1; }
.file-pill button:hover { color: var(--text-color); background: var(--border-color); }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 1100px) {
    .starter-grid { grid-template-columns: 1fr; }
    .starter-grid button { min-height: 84px; }
}
@media (max-width: 800px) {
    #chat-box { padding: 88px 16px calc(var(--composer-clearance, 124px) + 2px); scroll-padding: 88px 0 calc(var(--composer-clearance, 124px) + 2px); }
    body.composer-expanded #chat-box { padding-bottom: calc(var(--composer-clearance, 126px) + 26px); }
    #chat-box:has(.welcome-message) { overflow-y: auto; justify-content: flex-start; padding-top: 82px; padding-bottom: 118px; }
    body.composer-expanded #chat-box:has(.welcome-message) { padding-bottom: calc(var(--composer-clearance, 118px) + 26px); }
    #chat-box:has(.welcome-message) .welcome-message { transform: none; }
    .welcome-message { padding: 20px 6px 28px; }
    #input-area { padding: 20px 12px 12px; }
    #main-area > .jump-bottom-btn { bottom: calc(var(--composer-clearance, 86px) + 10px); }
}
@media (max-width: 560px) {
    .composer-main-row { gap: 4px; }
    /* Stop narrows the textarea while a turn runs: the placeholder ellipsizes instead of wrapping under the edge. */
    #prompt-input::placeholder { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
    .message:has(.user-label) .message-body { max-width: 88%; }
}

/* Reduced motion (FA §8.3): spinners and dots become static glyphs. */
@media (prefers-reduced-motion: reduce) {
    .message { animation: none; }
    .tool-inline-spinner,
    .work-pending .spinner {
        animation: none;
        border: 0;
        width: auto;
        height: auto;
        vertical-align: baseline;
    }
    .tool-inline-spinner::before,
    .work-pending .spinner::before { content: '…'; color: var(--gold-accent); }
    .think-chip[data-state="running"] .thinking-dots::after { animation: none; content: '…'; }
}