feat: Phase 1 Aether Drift — mobile-first grid layout and token migration

Replace Discord flex layout with CSS Grid on desktop (312px sidebar +
1fr main) and overlay drawer on mobile. Migrate all discord-* class
references to Aether Drift design tokens across 15 files (~200 refs).

Layout: ServerSidebar becomes a fixed glass strip (md:glass-strip),
ChannelSidebar gets pl-[72px] offset, bottom bar is a glass-bubble
(z-105), MessageInput floats as absolute glass pill on desktop (z-110).
MemberSidebar/ActivityPanel hidden on mobile via hidden md:block.

Z-index stack: MobileNav backdrop z-35, sidebar z-40, glass strip z-100,
bottom bar z-105, input bubble z-110, hamburger z-120, profile popout
z-145, device panels z-150, modals z-200.

packages/web/src/components/chat/MessageInput.tsx

@@ -216,16 +216,16 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
   };
 
   return (
-    <div className="px-4 pb-6 flex-shrink-0">
+    <div className="px-3 pb-3 flex-shrink-0 md:absolute md:bottom-3 md:left-3 md:right-3 md:z-[110] md:px-0 md:pb-0 md:glass-bubble md:rounded-[14px]">
       {replyTo && (
-        <div className="bg-discord-bg-hover rounded-t-lg px-4 py-2 flex items-center justify-between border-b border-discord-bg-tertiary/50">
-          <div className="flex items-center gap-1 text-[14px] text-discord-text-normal truncate">
+        <div className="bg-interactive-hover rounded-t-lg px-4 py-2 flex items-center justify-between border-b border-border-hard/50">
+          <div className="flex items-center gap-1 text-[14px] text-txt-message truncate">
             <span className="opacity-60">Replying to</span>
             <span className="font-bold">{replyTo.user.displayName ?? replyTo.user.username}</span>
           </div>
           <button
             onClick={() => setReplyTo(null)}
-            className="text-discord-text-muted hover:text-discord-text-primary transition-colors"
+            className="text-txt-tertiary hover:text-txt-primary transition-colors"
           >
             <svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor">
               <path d="M18.4 4L12 10.4L5.6 4L4 5.6L10.4 12L4 18.4L5.6 20L12 13.6L18.4 20L20 18.4L13.6 12L20 5.6L18.4 4Z" />
@@ -234,7 +234,7 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
         </div>
       )}
       <div
-        className={`relative bg-discord-bg-input ${replyTo ? 'rounded-b-lg' : 'rounded-lg'} overflow-visible`}
+        className={`relative bg-surface-input md:bg-transparent ${replyTo ? 'rounded-b-lg' : 'rounded-lg md:rounded-none'} overflow-visible`}
         onDrop={handleDrop}
         onDragOver={handleDragOver}
       >
@@ -249,9 +249,9 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
 
         {/* File previews */}
         {files.length > 0 && (
-          <div className="p-4 flex flex-wrap gap-4 bg-discord-bg-secondary/30">
+          <div className="p-4 flex flex-wrap gap-4 bg-surface-channel/30">
             {files.map((file, i) => (
-              <div key={i} className="relative group bg-discord-bg-secondary rounded-lg p-2 max-w-[200px] shadow-elevation-low border border-discord-bg-tertiary">
+              <div key={i} className="relative group bg-surface-channel rounded-lg p-2 max-w-[200px] shadow-elevation-low border border-border-hard">
                 {file.type.startsWith('image/') ? (
                   <img
                     src={URL.createObjectURL(file)}
@@ -259,7 +259,7 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
                     className="max-h-[150px] rounded object-cover"
                   />
                 ) : (
-                  <div className="flex items-center gap-2 text-sm text-discord-text-secondary py-4 px-2">
+                  <div className="flex items-center gap-2 text-sm text-txt-secondary py-4 px-2">
                     <svg className="w-8 h-8 opacity-60" fill="none" viewBox="0 0 24 24" stroke="currentColor">
                       <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 12h6m-6 4h6m2 5H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z" />
                     </svg>
@@ -268,7 +268,7 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
                 )}
                 <button
                   onClick={() => removeFile(i)}
-                  className="absolute -top-2 -right-2 w-7 h-7 bg-discord-red hover:bg-discord-red-hover shadow-elevation-high rounded-lg flex items-center justify-center text-white transition-colors z-10"
+                  className="absolute -top-2 -right-2 w-7 h-7 bg-accent-rose hover:bg-accent-rose/80 shadow-elevation-high rounded-lg flex items-center justify-center text-white transition-colors z-10"
                 >
                   <svg width="14" height="14" viewBox="0 0 16 16" fill="currentColor">
                     <path d="M5 2a1 1 0 011-1h4a1 1 0 011 1v1h3a1 1 0 110 2h-.08L13 14a2 2 0 01-2 2H5a2 2 0 01-2-2L2.08 5H2a1 1 0 110-2h3V2zm2 0v1h2V2H7z" />
@@ -283,7 +283,7 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
           {/* File attach button */}
           <button
             onClick={() => fileInputRef.current?.click()}
-            className="p-3 text-discord-text-muted hover:text-discord-text-secondary transition-colors sticky top-0"
+            className="p-3 text-txt-tertiary hover:text-txt-secondary transition-colors sticky top-0"
             title="Attach file"
           >
             <svg width="24" height="24" viewBox="0 0 24 24" fill="currentColor">
@@ -312,14 +312,14 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
             onKeyDown={handleKeyDown}
             onPaste={handlePaste}
             placeholder={`Message ${channelName.startsWith('@') ? channelName : `#${channelName}`}`}
-            className="flex-1 py-[11px] px-1 bg-transparent text-discord-text-primary placeholder-discord-text-muted/60 outline-none resize-none text-[15px] leading-[1.375rem] max-h-[50vh] scrollbar-thin"
+            className="flex-1 py-[11px] px-1 bg-transparent text-txt-primary placeholder-txt-tertiary/60 outline-none resize-none text-[15px] leading-[1.375rem] max-h-[50vh] scrollbar-thin"
             rows={1}
             disabled={isUploading}
           />
 
           {/* Send indicator */}
           {isUploading && (
-            <div className="p-3 text-discord-text-muted">
+            <div className="p-3 text-txt-tertiary">
               <svg className="w-5 h-5 animate-spin" viewBox="0 0 24 24" fill="none">
                 <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" />
                 <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4z" />
@@ -328,21 +328,21 @@ export function MessageInput({ channelId, channelName }: MessageInputProps) {
           )}
 
           {/* GIF button */}
-          <button className="p-2 text-discord-text-muted hover:text-discord-text-secondary transition-colors" title="GIF">
+          <button className="p-2 text-txt-tertiary hover:text-txt-secondary transition-colors" title="GIF">
             <svg width="24" height="24" viewBox="0 0 24 24" fill="currentColor">
               <path d="M2 5.5A2.5 2.5 0 0 1 4.5 3h15A2.5 2.5 0 0 1 22 5.5v13a2.5 2.5 0 0 1-2.5 2.5h-15A2.5 2.5 0 0 1 2 18.5v-13ZM5.1 14V10h3.2v1.2H6.5v.6h1.6v1.1H6.5V14H5.1Zm4.5 0V10h1.4v4H9.6Zm2.5 0V10h3.2v1.2h-1.8v.5h1.6v1h-1.6V14h-1.4Z" />
             </svg>
           </button>
 
           {/* Sticker button */}
-          <button className="p-2 text-discord-text-muted hover:text-discord-text-secondary transition-colors" title="Stickers">
+          <button className="p-2 text-txt-tertiary hover:text-txt-secondary transition-colors" title="Stickers">
             <svg width="24" height="24" viewBox="0 0 24 24" fill="currentColor">
               <path d="M12.5 2C6.81 2 2 6.81 2 12.5S6.81 23 12.5 23c1.31 0 2.56-.25 3.73-.7l5.07-5.07c.45-1.17.7-2.42.7-3.73C22 7.81 17.19 2 12.5 2Zm0 19c-4.69 0-8.5-3.81-8.5-8.5S7.81 4 12.5 4 21 7.81 21 12.5c0 .89-.14 1.74-.4 2.54l-3.56 3.56c-.8.26-1.65.4-2.54.4ZM8 11.5c.83 0 1.5-.67 1.5-1.5S8.83 8.5 8 8.5 6.5 9.17 6.5 10s.67 1.5 1.5 1.5Zm6 0c.83 0 1.5-.67 1.5-1.5s-.67-1.5-1.5-1.5-1.5.67-1.5 1.5.67 1.5 1.5 1.5Zm-1 3.5c-2.33 0-4.31-1.46-5.11-3.5h10.22c-.8 2.04-2.78 3.5-5.11 3.5Z" />
             </svg>
           </button>
 
           {/* Emoji button */}
-          <button className="p-2 text-discord-text-muted hover:text-discord-text-secondary transition-colors" title="Emoji">
+          <button className="p-2 text-txt-tertiary hover:text-txt-secondary transition-colors" title="Emoji">
             <svg width="24" height="24" viewBox="0 0 24 24" fill="currentColor">
               <path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm0 18c-4.41 0-8-3.59-8-8s3.59-8 8-8 8 3.59 8 8-3.59 8-8 8zm3.5-9c.83 0 1.5-.67 1.5-1.5S16.33 8 15.5 8 14 8.67 14 9.5s.67 1.5 1.5 1.5zm-7 0c.83 0 1.5-.67 1.5-1.5S9.33 8 8.5 8 7 8.67 7 9.5s.67 1.5 1.5 1.5zm3.5 6.5c2.33 0 4.31-1.46 5.11-3.5H6.89c.8 2.04 2.78 3.5 5.11 3.5z" />
             </svg>

packages/web/src/components/chat/MessageList.tsx

@@ -124,7 +124,7 @@ export function MessageList({ channelId }: MessageListProps) {
 
       {!hasMore && <WelcomeHeader channelId={channelId} />}
 
-      <div className="pb-6">
+      <div className="pb-6 md:pb-[88px]">
         {messages.map((msg, i) => {
           const prevMsg = messages[i - 1];
           const showDate = shouldShowDateDivider(prevMsg, msg);
@@ -134,11 +134,11 @@ export function MessageList({ channelId }: MessageListProps) {
             <React.Fragment key={msg.id}>
               {showDate && (
                 <div className="flex items-center px-4 my-6 select-none pointer-events-none">
-                  <div className="flex-1 h-[1px] bg-discord-modifier-accent" />
-                  <span className="px-2 text-[12px] font-bold text-discord-text-muted leading-tight">
+                  <div className="flex-1 h-[1px] bg-interactive-muted" />
+                  <span className="px-2 text-[12px] font-bold text-txt-tertiary leading-tight">
                     {formatDateDivider(msg.createdAt)}
                   </span>
-                  <div className="flex-1 h-[1px] bg-discord-modifier-accent" />
+                  <div className="flex-1 h-[1px] bg-interactive-muted" />
                 </div>
               )}
               <Message
@@ -175,35 +175,35 @@ function WelcomeHeader({ channelId }: { channelId: string }) {
         <div className="mb-2">
           <Avatar src={otherUser?.avatar} name={displayName} size={80} />
         </div>
-        <h3 className="text-[32px] leading-10 font-bold text-discord-text-primary">{displayName}</h3>
-        <p className="text-discord-text-secondary text-[14px] mt-1">
+        <h3 className="text-[32px] leading-10 font-bold text-txt-primary">{displayName}</h3>
+        <p className="text-txt-secondary text-[14px] mt-1">
           This is the beginning of your direct message history with <strong>@{username}</strong>.
         </p>
         {isFriend && otherUser && (
           <div className="mt-4">
             <button
               onClick={() => removeFriend(otherUser.id)}
-              className="px-4 py-1.5 bg-discord-bg-accent hover:bg-discord-bg-surface-higher text-[14px] font-medium text-discord-text-primary rounded-[3px] transition-colors"
+              className="px-4 py-1.5 bg-surface-elevated hover:bg-surface-elevated text-[14px] font-medium text-txt-primary rounded-[3px] transition-colors"
             >
               Remove Friend
             </button>
           </div>
         )}
-        <div className="mt-6 border-b border-discord-modifier-accent" />
+        <div className="mt-6 border-b border-interactive-muted" />
       </div>
     );
   }
 
   return (
     <div className="px-4 pt-8 pb-4">
-      <div className="w-[68px] h-[68px] rounded-full bg-discord-bg-accent flex items-center justify-center mb-4 text-white">
+      <div className="w-[68px] h-[68px] rounded-full bg-surface-elevated flex items-center justify-center mb-4 text-white">
         <svg width="42" height="42" viewBox="0 0 24 24" fill="currentColor">
           <path d="M5.88657 21C5.57547 21 5.3399 20.7189 5.39427 20.4126L6.00001 17H2.59511C2.28449 17 2.04905 16.7198 2.10259 16.4138L2.27759 15.4138C2.31946 15.1746 2.52722 15 2.77011 15H6.35001L7.41001 9H4.00511C3.69449 9 3.45905 8.71977 3.51259 8.41381L3.68759 7.41381C3.72946 7.17456 3.93722 7 4.18011 7H7.76001L8.39677 3.41262C8.43914 3.17391 8.64664 3 8.88907 3H9.87344C10.1845 3 10.4201 3.28107 10.3657 3.58738L9.76001 7H15.76L16.3968 3.41262C16.4391 3.17391 16.6466 3 16.8891 3H17.8734C18.1845 3 18.4201 3.28107 18.3657 3.58738L17.76 7H21.1649C21.4755 7 21.711 7.28023 21.6574 7.58619L21.4824 8.58619C21.4406 8.82544 21.2328 9 20.9899 9H17.41L16.35 15H19.7549C20.0655 15 20.301 15.2802 20.2474 15.5862L20.0724 16.5862C20.0306 16.8254 19.8228 17 19.5799 17H16L15.3632 20.5874C15.3209 20.8261 15.1134 21 14.8709 21H13.8866C13.5755 21 13.3399 20.7189 13.3943 20.4126L14 17H8.00001L7.36325 20.5874C7.32088 20.8261 7.11337 21 6.87094 21H5.88657ZM9.41001 9L8.35001 15H14.35L15.41 9H9.41001Z" />
         </svg>
       </div>
-      <h3 className="text-[32px] leading-10 font-bold text-discord-text-primary">Welcome to the channel!</h3>
-      <p className="text-discord-text-secondary text-[16px] mt-2">This is the start of the conversation.</p>
-      <div className="mt-6 border-b border-discord-modifier-accent" />
+      <h3 className="text-[32px] leading-10 font-bold text-txt-primary">Welcome to the channel!</h3>
+      <p className="text-txt-secondary text-[16px] mt-2">This is the start of the conversation.</p>
+      <div className="mt-6 border-b border-interactive-muted" />
     </div>
   );
 }