Use the large field size for the Ask AI bar on every screen

The larger field was limited to small screens through one-off padding
overrides. The bar now uses the Input's large size everywhere, the same as
the Assistant's chat input, so desktop gets the bigger field too and the
overrides go away.

Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011HgypMzRurWjvNb5ZswrNd

packages/gitbook/src/components/AIChat/AIChatPageBar.tsx

@@ -92,7 +92,7 @@ export function AIChatPageBar() {
                 ) : null}
                 {showSuggestions ? (
                     // The input stays in flow on top of the card, so focusing it never moves it; the bottom padding leaves its room.
-                    <div className="pb-13 absolute -inset-x-2 -bottom-2 flex flex-col border border-tint bg-tint-base p-2 shadow-lg rounded-corners:rounded-[1.25rem] circular-corners:rounded-[1.75rem] max-lg:pb-16">
+                    <div className="absolute -inset-x-2 -bottom-2 flex flex-col border border-tint bg-tint-base p-2 pb-16 shadow-lg rounded-corners:rounded-[1.25rem] circular-corners:rounded-[1.75rem]">
                         {suggestions.map((question, index) => (
                             <Button
                                 key={question}
@@ -114,6 +114,7 @@ export function AIChatPageBar() {
                     name="ai-page-bar-input"
                     multiline
                     resize
+                    sizing="large"
                     rows={1}
                     label={tString(
                         language,
@@ -150,9 +151,8 @@ export function AIChatPageBar() {
                     onSubmit={ask}
                     className={tcls(
                         // The send button is overlaid, so the textarea spans the full width and scrolls at the right edge.
-                        'bg-tint-base/9 pl-3 text-sm contrast-more:bg-tint-base [&_textarea]:max-h-32 [&_textarea]:pr-9',
-                        // A larger field on small screens; iOS also zooms the page when focusing text under 16px.
-                        'max-lg:p-3 max-lg:pl-4 max-lg:text-base max-lg:[&_textarea]:-m-3 max-lg:[&_textarea]:p-3 max-lg:[&_textarea]:pr-12',
+                        // text-base because iOS zooms the page when focusing a field with text under 16px.
+                        'bg-tint-base/9 pl-4 text-base contrast-more:bg-tint-base [&_textarea]:max-h-32 [&_textarea]:pr-12',
                         // The larger shadow would be cut off at the bottom edge of a small screen.
                         showSuggestions ? null : 'shadow-lg backdrop-blur-lg max-lg:shadow-sm'
                     )}
@@ -165,7 +165,7 @@ export function AIChatPageBar() {
                     label={tString(language, 'send')}
                     disabled={!value.trim()}
                     onClick={() => ask(value)}
-                    className="max-lg:bottom-2.25 max-lg:right-2.25 absolute bottom-1.5 right-1.5 max-lg:p-1.5"
+                    className="bottom-2.25 right-2.25 absolute p-1.5"
                 />
             </div>
             <div ref={restRef} />