/* App shell + real-interaction styles layered over base.css (extracted from mocks/claude/mock-v2.1.html)

   Layout model — one set of screens, responsive at every size:
   - #app always fills the viewport. Below 900px it shows one screen at a time; from 900px app.js's frame()
     composes the same screens side by side (rail, chat list, conversation, side panel).
   - #app and each desktop pane are size containers, so components size themselves to the space they get
     (cqw units and @container rules), not to the device. A conversation looks the same in a 700px phone-less
     window as in a 700px desktop pane.
   - Screens keep their content in a readable column (--gx gutters) instead of stretching edge to edge. */

/* Safari tints the status-bar strip with a flat colour (iOS 26: the body background; older: theme-color), so both match --bg,
   and anything drawn at the very top of a screen has to fade into --bg or it shows as a hard band under the clock */
html,body{height:100%;background:var(--bg);overscroll-behavior:none;touch-action:pan-x pan-y;-webkit-text-size-adjust:100%;-webkit-tap-highlight-color:transparent}
/* min-height:0 drops base.css's 100vh, which iOS measures with the toolbars hidden and so made the page scroll a little */
body{overflow:hidden;min-height:0}
#app{position:relative;height:100dvh;background:var(--bg);overflow:hidden;container-type:inline-size}
button,[data-act]{cursor:pointer}
button:disabled{opacity:.5;cursor:not-allowed}
:focus-visible{outline:2px solid var(--you-l);outline-offset:2px}

/* screens: a 22px gutter on phones that grows to centre a 560px column on anything wider */
.scr{--gx:max(22px,calc((100cqw - 560px) / 2));position:absolute;inset:0;display:flex;flex-direction:column;overflow:hidden;padding:max(30px,calc(env(safe-area-inset-top) + 10px)) var(--gx) 0}
.scr.np{padding:0}
.sc{flex:1;min-height:0;overflow-y:auto;overflow-x:hidden;overscroll-behavior:contain;margin:0 calc(-1 * var(--gx));padding:0 var(--gx) 24px;scrollbar-width:none}
.sc::-webkit-scrollbar{display:none}
.scr.np>.sc{margin:0;padding:0}
.scr.hasnav .sc{padding-bottom:calc(88px + max(16px,env(safe-area-inset-bottom)))}
.scr.np>.chd{padding-top:max(24px,calc(env(safe-area-inset-top) + 8px))}
/* the glow sits off the top edge and the first layer fades it to --bg there, so it runs into Safari's status-bar tint without a seam */
.scr.land{background:linear-gradient(var(--bg),rgba(13,14,17,0) 150px),radial-gradient(80% 40% at 100% 9%,rgba(47,109,240,.26),transparent 70%),radial-gradient(70% 36% at 0% 58%,rgba(143,180,255,.08),transparent 72%),var(--bg)}
/* the landing scrolls once its content outgrows the screen; until then it fits exactly and nothing moves */
.scr.land{overflow-y:auto;overscroll-behavior:contain;scrollbar-width:none}
.scr.land::-webkit-scrollbar{display:none}
.scr .land-body{display:flex;flex-direction:column;min-height:100%}
.fine,.lead{text-wrap:pretty}
/* iOS zooms into any focused field under 16px and stays zoomed */
@supports (-webkit-touch-callout:none){input,select,textarea{font-size:16px!important}}
.cta,.acts{margin-top:auto;padding:12px 0 max(24px,env(safe-area-inset-bottom));display:grid;gap:10px;flex:none}
.cta .fine{cursor:pointer}

/* real inputs inside mock input chrome */
.inp input,.search input,.cmp input,.comp input,.sheet input.big{flex:1;min-width:0;background:none;border:0;outline:0;color:var(--tx);font:inherit}
.inp input::placeholder,.search input::placeholder,.comp input::placeholder,.sheet input::placeholder{color:var(--tx3)}
.inp:focus-within{border-color:var(--you);box-shadow:0 0 0 4px rgba(47,109,240,.14)}
.lang{position:relative}
.lang select{position:absolute;inset:0;width:100%;opacity:0;cursor:pointer}
.captcha{margin-top:14px}.captcha:empty{display:none}
.err{color:var(--danger);font-size:13px;margin-top:10px;line-height:1.35}
.chd>.ic{cursor:pointer}
.pend{font-style:italic;opacity:.75}
.ldots{display:inline-flex;gap:3px;margin-left:6px;vertical-align:middle}
.ldots i{width:4px;height:4px;border-radius:50%;background:currentColor;opacity:.5;animation:bl 1.2s infinite}
.ldots i:nth-child(2){animation-delay:.15s}.ldots i:nth-child(3){animation-delay:.3s}
@keyframes bl{0%,60%,100%{opacity:.25}30%{opacity:.9}}
.row{cursor:pointer}
.row .l1 .ic{color:var(--tx3)}
.row .mk{display:flex;align-items:center;gap:6px}
.row .ic.pinned{color:var(--tx3)}
/* the newest message request inside the All tab, with a way through to the rest */
.rqg{border-bottom:1px solid var(--line)}
.rqg .row{border-bottom:0}
.rqm{display:flex;align-items:center;gap:7px;margin:-3px 0 13px 59px;padding:8px 10px;border-radius:8px;background:rgba(255,255,255,.045);font-size:13px;color:var(--tx2);cursor:pointer}
.rqm span{min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.rqm b{margin-left:auto;font-weight:600;color:var(--tx);white-space:nowrap}
.tabs span{cursor:pointer}
.nav .t{cursor:pointer}
.empty{margin-top:42px;text-align:center;color:var(--tx3);font-size:14.5px;line-height:1.5;padding:0 18px}
.empty .ic{width:34px;height:34px;color:var(--tx3);margin-bottom:10px}
.empty b{display:block;color:var(--tx);font:700 21px var(--disp);margin-bottom:6px;letter-spacing:-.01em}
.tk{cursor:pointer}
.tks{display:grid;grid-template-columns:repeat(auto-fill,minmax(min(310px,100%),1fr));gap:12px;margin-top:16px}
.tks .tkh{margin-top:0}
.tk.tkh .q.qr{color:var(--ink)}
.tkv .qc .qr{color:var(--ink)}
.cd .qwrap .q{color:var(--ink)}
.opt,.dopt,.segs span,.seg span{cursor:pointer}
.tog{cursor:pointer;transition:background .15s}
.tog.on{background:var(--you)}
.tog.on::after{transform:translateX(14px);background:#fff}
.tog::after{transition:transform .15s}
.acr{cursor:pointer}
.ppl .p{cursor:pointer}

/* overlays: bottom sheets on phones, centred dialogs once there's room around them */
.scrim{position:absolute;inset:0;background:rgba(0,0,0,.55);z-index:20;animation:fade .15s}
@keyframes fade{from{opacity:0}}
@keyframes rise{from{transform:translateY(24px);opacity:0}}
@keyframes pop{from{opacity:0;transform:translate(-50%,-47%)}}
.sheet h3{font:700 22px var(--disp);letter-spacing:-.015em;margin:2px 0 6px}
.sheet .sub{color:var(--tx2);font-size:14px;line-height:1.4;margin-bottom:12px}
.sheet .out{max-height:150px;overflow:auto}
.toast{position:absolute;left:50%;bottom:96px;transform:translateX(-50%);z-index:40;background:var(--paper);color:var(--ink);font-weight:600;font-size:14px;padding:11px 16px;border-radius:9px;box-shadow:0 14px 30px -10px rgba(0,0,0,.7);animation:rise .2s;max-width:86%;text-align:center}
@media (min-width:600px){
  .scrim{background:rgba(0,0,0,.6);backdrop-filter:blur(3px)}
  .sheet{left:50%;right:auto;top:50%;bottom:auto;width:min(480px,calc(100% - 48px));max-height:min(760px,calc(100% - 64px));border:1px solid var(--line2);border-radius:16px;padding:24px 26px 26px;transform:translate(-50%,-50%);animation:pop .18s;box-shadow:0 40px 90px -30px rgba(0,0,0,.9)}
  .sheet .grab{display:none}
  .toast{bottom:32px}
  .sheet:has(>.md),.sheet:has(>.ep){top:auto;bottom:0;width:min(520px,100%);max-height:88%;border-bottom:0;border-radius:16px 16px 0 0;padding:20px 22px 24px;transform:translateX(-50%);animation:riseC .2s}
}
@keyframes riseC{from{transform:translate(-50%,24px);opacity:0}}
.boot{display:grid;place-items:center;height:100%}
.boot svg{width:64px;height:54px;animation:pulse 1.2s infinite}
@keyframes pulse{50%{opacity:.4}}
.dbanner{margin:12px 14px 0;padding:11px 13px;border:1px solid rgba(255,93,108,.4);background:linear-gradient(100deg,rgba(255,93,108,.13),rgba(255,93,108,.02));border-radius:10px;font-size:13px;color:var(--tx2);line-height:1.4;display:flex;gap:10px;align-items:center}
.dbanner b{color:var(--danger);font-weight:700}
.dbanner button{margin-left:auto;flex:none;font-weight:700;font-size:13px;color:var(--tx);border:1px solid var(--line2);border-radius:7px;padding:6px 10px}
.reqb button.in{margin-top:12px;height:40px;padding:0 14px;font-weight:700;font-size:14px;border-radius:8px;background:var(--paper);color:var(--ink)}
.stp div.done{color:var(--tx2)}
.stp div.done .m{background:var(--you);border-color:var(--you);color:#fff}
.stp div.fail{color:var(--danger)}
.sheet input.big{width:100%;height:48px;border:1px solid var(--line2);border-radius:9px;background:var(--bg);padding:0 13px;font-size:16px;margin:6px 0 4px}
.sheet input.big:focus{border-color:var(--you)}
.lock{display:flex;align-items:center;gap:6px;color:var(--tx3);font-size:12.5px}
.copied{color:var(--you-l)}
.cd .lbl .ic,.pgh .h2{cursor:pointer}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}
/* brand lockup (was part of the mock's board chrome) */
.brand{display:flex;align-items:center;gap:10px}
.brand svg{width:34px;height:29px;flex:none}
.wm{font:800 21px/1 var(--disp);letter-spacing:-.02em;white-space:nowrap}
.wm i{font-style:normal;color:var(--you-l)}
.lsteps{display:none}

/* conversation */
.chd .who{flex:1;min-width:0;display:flex;align-items:center;gap:11px;border-radius:10px}
.chd .who[data-act]{cursor:pointer}
.chd .tt b{display:flex;align-items:center;gap:7px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chd .tt b .on{width:8px;height:8px;border-radius:50%;background:var(--ok);flex:none}
/* the clip hides each line's time past the right edge; dragging the track left brings them in */
.msgs{overflow-x:clip;touch-action:pan-y;-webkit-user-select:none;user-select:none;-webkit-touch-callout:none}
.track{display:flex;flex-direction:column;transition:transform .3s cubic-bezier(.2,.8,.2,1)}
.track.drag{transition:none}
.track>.msg{margin-top:10px}
.day{align-self:center;font-size:12px;color:var(--tx3);margin:18px 0 8px}
.sys{margin:10px 0}
.run{display:flex;gap:8px;margin-top:10px;width:100%}
.run.me{flex-direction:column;align-items:flex-end}
.run .slot{width:30px;flex:none;display:flex;align-items:flex-end}
.run .col{flex:1;display:flex;flex-direction:column;gap:2px;min-width:0}
.run.me .col{align-self:stretch}
.run .by{font-size:12px;color:var(--tx3);margin:0 0 3px 12px;font-weight:600}
.rcpt{font-size:11.5px;color:var(--tx3);margin:4px 4px 0 0}
.line{display:flex;position:relative}
.run.me .line{justify-content:flex-end}
/* one message: optional reply quote, the bubble, its reactions and the hover bar */
.bw{position:relative;max-width:84%;display:flex;flex-direction:column;align-items:flex-start;transition:transform .25s cubic-bezier(.2,.8,.2,1)}
.run.me .bw{align-items:flex-end}
.bw.drag{transition:none}
.run .bb,.mstack .bb{max-width:100%;padding:9px 13px;font-size:15.5px;line-height:1.38;background:var(--s2);border:0;border-radius:18px;overflow-wrap:anywhere;white-space:pre-wrap;transition:filter .12s}
.run .bb.mine,.mstack .bb.mine{background:var(--you);color:var(--on-you)}
.run .bb.gone{background:none;box-shadow:inset 0 0 0 1px var(--line2);color:var(--tx3);font-style:italic}
.run .bb.lifted{visibility:hidden}
.run .bb[data-id]:active{filter:brightness(1.2)}
.bb.flash{animation:flash 1.1s}
@keyframes flash{0%,45%{box-shadow:0 0 0 3px var(--you-l)}100%{box-shadow:0 0 0 0 transparent}}
/* a run reads as one block: only the outer corners stay round */
.run:not(.me) .line+.line .bb{border-top-left-radius:6px}
.run:not(.me) .line:has(+.line) .bb{border-bottom-left-radius:6px}
.run.me .line+.line .bb{border-top-right-radius:6px}
.run.me .line:has(+.line) .bb{border-bottom-right-radius:6px}
.ts{position:absolute;right:-96px;top:50%;transform:translateY(-50%);width:66px;font:500 11px/1 var(--mono);color:var(--tx3);white-space:nowrap}
.ri{position:absolute;right:calc(100% + 12px);top:50%;margin-top:-15px;width:30px;height:30px;border-radius:50%;background:var(--s2);display:grid;place-items:center;color:var(--tx2);opacity:0;pointer-events:none}
/* mouse: the bar fades in after a short dwell and lingers so the pointer can reach it */
.hb{position:absolute;bottom:calc(100% + 4px);right:-10px;display:flex;gap:1px;padding:2px;background:var(--s2);border:1px solid var(--line2);border-radius:999px;box-shadow:0 6px 18px rgba(0,0,0,.35);z-index:2;opacity:0;visibility:hidden;transform:translateY(3px);transition:opacity .12s .3s,transform .12s .3s,visibility 0s .42s}
.run.me .hb{right:auto;left:-10px}
.hb.side{bottom:auto;right:auto;left:calc(100% + 6px)}
.run.me .hb.side{left:auto;right:calc(100% + 6px)}
.hb button{width:26px;height:26px;border-radius:999px;display:grid;place-items:center;color:var(--tx2)}
.hb button:hover{background:var(--s3);color:var(--tx)}
.mouse .line:hover .hb,.line:has(:focus-visible) .hb,.line.act .hb{opacity:1;visibility:visible;transform:none;transition:opacity .12s .2s,transform .12s .2s,visibility 0s .2s}
#app:not(.mouse) .hb{display:none}
.rxs{display:flex;gap:4px;margin:-6px 8px 0;position:relative;z-index:1}
.rx{display:flex;align-items:center;gap:3px;background:var(--s2);border:2px solid var(--bg);border-radius:999px;padding:1px 7px;font-size:13px;line-height:1.35}
.rx b{font:600 11.5px/1 var(--sans);color:var(--tx2)}
.rx.mine{background:#1f3156}
.quote{display:flex;flex-direction:column;align-items:flex-start;max-width:100%;text-align:left;padding:6px 10px;margin-bottom:3px;border-radius:12px;background:var(--s1);border-left:3px solid var(--tx3);font-size:12.5px;color:var(--tx2);line-height:1.3}
.quote b{font-weight:650;color:var(--tx);font-size:12px}
.quote span{max-width:min(230px,100%);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.run.me .quote{border-left-color:var(--you-l)}
.rpl{flex:none;display:flex;align-items:center;gap:10px;padding:10px max(14px,calc((100cqw - 880px) / 2 + 28px)) 0;border-top:1px solid var(--line)}
.rpl:empty{display:none}
.rpl:not(:empty)+.comp{border-top:0}
.rpq{flex:1;min-width:0;border-left:3px solid var(--you);padding:2px 0 2px 10px;display:flex;flex-direction:column;gap:2px}
.rpq b{font-size:12.5px;font-weight:650;color:var(--you-l)}
.rpq span{font-size:13px;color:var(--tx2);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.rpl button{width:30px;height:30px;border-radius:50%;display:grid;place-items:center;color:var(--tx3)}
.tip{position:absolute;bottom:88px;left:50%;transform:translateX(-50%);max-width:calc(100% - 24px);background:var(--s2);border:1px solid var(--line2);color:var(--tx2);font-size:12.5px;padding:7px 12px;border-radius:999px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;pointer-events:none;z-index:3;animation:fade .35s}

/* hold menu: the message lifts out of a dimmed chat, reactions above, actions below */
.menu{position:absolute;inset:0;z-index:30;background:rgba(5,6,8,.55);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);animation:fade .16s}
.mstack{position:absolute;display:flex;flex-direction:column;gap:8px;align-items:flex-start;transform-origin:top left;animation:lift .22s cubic-bezier(.2,.9,.3,1.15)}
.mstack.me{align-items:flex-end;transform-origin:top right}
@keyframes lift{from{transform:scale(.94);opacity:.3}}
.mstack>.bb{max-width:calc(100cqw - 24px);max-height:40dvh;overflow:hidden;box-shadow:0 10px 30px rgba(0,0,0,.45)}
.rbar{display:flex;gap:2px;padding:5px;background:var(--s2);border:1px solid var(--line2);border-radius:999px;box-shadow:0 10px 30px rgba(0,0,0,.4)}
.rbar button{width:40px;height:40px;border-radius:50%;font-size:23px;line-height:1;display:grid;place-items:center;transition:transform .12s}
.rbar button:active{transform:scale(1.18)}
.rbar button.on,.eg button.on{background:var(--you)}
.rbar .plus{color:var(--tx2);background:var(--s3)}
.macts{min-width:220px;background:var(--s2);border:1px solid var(--line2);border-radius:14px;overflow:hidden;box-shadow:0 10px 30px rgba(0,0,0,.4)}
.macts button{display:flex;align-items:center;justify-content:space-between;gap:24px;width:100%;padding:12px 14px;font-size:15px;text-align:left}
.macts button+button{border-top:1px solid var(--line)}
.macts .ic{color:var(--tx2)}
.macts .dg,.macts .dg .ic{color:var(--danger)}
.pop{position:absolute;z-index:22;animation:lift .16s cubic-bezier(.2,.9,.3,1.15)}

/* message details and the emoji picker come up from the bottom at every size */
.ep h3{margin-bottom:4px}
.ep .eyebrow{margin:16px 2px 6px}
.eg{display:grid;grid-template-columns:repeat(8,1fr);gap:2px}
.eg button{aspect-ratio:1;font-size:24px;line-height:1;border-radius:10px}
.md .eyebrow{display:block;margin:20px 4px 8px}
.md-h{display:flex;align-items:center;gap:10px}
.md-h>div:not(.av){flex:1;min-width:0}
.md-h b{font-weight:650;display:block}
.md-h small{display:block;font-size:12.5px;color:var(--tx3);margin-top:1px}
.md-h .x{width:32px;height:32px;border-radius:50%;background:var(--s2);display:grid;place-items:center;color:var(--tx2)}
.qa{display:grid;grid-auto-flow:column;grid-auto-columns:minmax(0,1fr);gap:8px;margin-top:16px}
.qa button{display:flex;flex-direction:column;align-items:center;gap:6px;padding:12px 4px 10px;background:var(--s2);border-radius:14px;font-size:12.5px;color:var(--tx2)}
.qa .ic{color:var(--tx)}
.qa .dg,.qa .dg .ic{color:var(--danger)}
.md-tx,.md-card{border:1px solid var(--line);border-radius:14px;overflow:hidden}
.md-tx>div{padding:12px 14px}
.md-tx>div+div,.md-r+.md-r{border-top:1px solid var(--line)}
.md-tx .eyebrow{margin:0 0 6px}
/* original and translation share one type size, so neither looks secondary by accident */
.md-tx p{font-size:15px;line-height:1.4;color:var(--tx);overflow-wrap:anywhere;white-space:pre-wrap}
.md-r{display:flex;align-items:center;gap:12px;padding:12px 14px}
.md-r>div:not(.av){flex:1;min-width:0}
.md-r b{display:block;font-weight:600;font-size:14.5px}
.md-r small{display:block;font-size:12.5px;color:var(--tx3);margin-top:2px}
.md-r .ai{width:32px;height:32px;border-radius:9px;background:var(--s2);display:grid;place-items:center;color:var(--tx2);flex:none}
.md-r .re{font-size:20px;line-height:1}

/* chat details */
.dh{display:flex;flex-direction:column;align-items:center;text-align:center;padding:8px 0 22px}
.dh .h2{font-size:26px;margin-top:14px}
.dh .h2 .ic{color:var(--tx3)}
.dh small{font-size:13.5px;color:var(--tx2);margin-top:5px}
.dsec{display:block;margin:22px 4px 8px}
.dcard{background:var(--s1);border:1px solid var(--line);border-radius:11px;padding:0 14px;margin-top:0}
.dcard .acr:last-child{border-bottom:0}
.ppl{margin-top:0}
.avw{position:relative;display:inline-block;flex:none}
.pd{position:absolute;right:-2px;bottom:-2px;width:11px;height:11px;border-radius:50%;background:var(--tx3);border:2px solid var(--s1)}
.pd.on{background:var(--ok)}
.dh .pd{width:16px;height:16px;border-width:3px;border-color:var(--bg)}
.ppl .ai.inv{width:30px;height:30px;border-radius:8px;background:var(--s3);display:grid;place-items:center;color:var(--you-l)}
.ppl b.inv{color:var(--you-l)}
.trn{display:flex;align-items:center;gap:13px;padding:13px 0}
.trn .ai{width:38px;height:38px;border-radius:8px;background:var(--s3);display:grid;place-items:center;color:var(--tx2);flex:none}
.trn>div{flex:1;min-width:0}
.trn b{display:block;font-size:15px;font-weight:600}
.trn small{display:block;font-size:12.5px;color:var(--tx3);margin-top:2px}
.rdy{display:flex;align-items:center;gap:6px;font-size:12.5px;color:var(--ok);font-weight:600;flex:none}
.rdy i{width:7px;height:7px;border-radius:50%;background:var(--ok)}
.rdy.wait{color:var(--tx3)}

/* conversation: spacing follows the width of whatever holds it (the whole screen on a phone, a pane on desktop).
   Kept below every base rule it adjusts, since @container adds no specificity. */
@container (min-width:600px){
  .chd{padding-left:24px;padding-right:24px}
  .reqb,.dbanner{margin:14px 24px 0}
  .msgs{padding:20px 28px 18px}
  .bw{max-width:min(72%,620px)}
  .comp{padding-left:max(24px,calc((100cqw - 880px) / 2 + 28px));padding-right:max(24px,calc((100cqw - 880px) / 2 + 28px))}
}
/* short screens (a phone on its side): the header and composer give their height to the messages until the phone is upright again */
@media (max-height:500px){
  .scr.np>.chd{padding-top:max(10px,env(safe-area-inset-top));padding-bottom:8px}
  .comp{padding-top:8px;padding-bottom:max(10px,env(safe-area-inset-bottom))}
}

/* pointer affordances, for any screen size with a mouse or trackpad */
@media (hover:hover){
  .btn.go:hover,.ibtn.go:hover,.comp .send:hover,.sheet .cmp .send:hover{filter:brightness(1.1)}
  .btn.ln:hover,.ibtn:not(.go):hover,.mini:hover{background:var(--s2)}
  .res:hover{background:var(--s1)}
  .acr:hover .ai{background:var(--you-t);color:var(--you-l)}
  .acr.dg:hover .ai{background:rgba(255,93,108,.22);color:var(--danger)}
  .acr:hover>.ic:last-child{transform:translateX(2px)}
  .acr>.ic:last-child{transition:transform .12s}
  .opt:not(.on):hover,.dopt:not(.on):hover,.tk:hover,.segs span:not(.on):hover{border-color:var(--tx3)}
  .rws .r:hover,.ppl .p:hover{background:var(--s2)}
  .tabs span:not(.on):hover,.lnk:hover{color:var(--tx)}
  .rqm:hover{background:rgba(255,255,255,.08);color:var(--tx)}
}

/* ───────── desktop (≥900px, matched by DESK in app.js): several panes at once ─────────
   The same screens, arranged side by side: the floating tab bar becomes the rail, the chat list stays beside the conversation. */
@media (min-width:900px){
  /* shell */
  .dsk{position:absolute;inset:0;display:grid}
  .dsk.app{grid-template-columns:84px minmax(0,1fr)}
  .dsk.app.has-list{grid-template-columns:84px clamp(320px,28vw,400px) minmax(0,1fr)}
  .dsk.app.has-list.has-side{grid-template-columns:84px clamp(320px,26vw,380px) minmax(0,1fr) 380px}
  .pane{position:relative;min-width:0;overflow:hidden;container-type:inline-size;background:var(--bg)}
  .lp{border-right:1px solid var(--line)}
  .sp{border-left:1px solid var(--line)}
  .dsk .nav{display:none}
  .dsk .hasnav .sc{padding-bottom:32px}
  .dsk .scr:not(.np){--gx:28px;padding-top:28px}
  .dsk .lp .scr{--gx:20px;padding-top:24px}
  .dsk .mp .scr:not(.np){--gx:max(40px,calc((100cqw - 720px) / 2));padding-top:40px}
  .dsk .sp .scr{--gx:22px;padding-top:22px}

  /* rail */
  .rail{background:var(--page);border-right:1px solid var(--line);display:flex;flex-direction:column;align-items:center;padding:20px 0 18px;min-height:0}
  .rail .rl{display:grid;place-items:center;width:56px;height:48px;margin-bottom:18px;border-radius:12px}
  .rail .rl svg{width:38px;height:32px}
  .rail nav{display:flex;flex-direction:column;gap:6px}
  .rail .ri{position:relative;width:64px;height:58px;border-radius:12px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;color:var(--tx3);font:600 11px/1 var(--sans);transition:background .12s,color .12s}
  .rail .ri:hover{color:var(--tx);background:var(--s1)}
  .rail .ri.on{background:var(--you-t);color:var(--you-l)}
  .rail .ri .badge{position:absolute;top:5px;right:9px;min-width:18px;height:18px;padding:0 5px;font-size:10.5px;line-height:18px;box-shadow:0 0 0 2px var(--page)}
  .rail .ri.on .badge{box-shadow:0 0 0 2px #0b1730}
  .rail .sv,.rail .rme{margin-top:auto}
  .rail .rme{border-radius:12px;padding:3px}
  .rail .rme .av{width:40px;height:40px;border-radius:10px;font-size:16px;transition:box-shadow .12s}
  .rail .rme:hover .av{box-shadow:0 0 0 2px var(--you-l)}

  /* chat list pane */
  .dsk .lp .h2{font-size:30px}
  .dsk .lp .row{position:relative;margin:0 -10px;padding:12px 10px;border-bottom:0;border-radius:10px}
  .dsk .lp .row+.row::before{content:"";position:absolute;left:10px;right:10px;top:0;border-top:1px solid var(--line)}
  .dsk .lp .row:hover{background:var(--s1)}
  .dsk .lp .row:hover::before,.dsk .lp .row:hover+.row::before,.dsk .lp .row.on::before,.dsk .lp .row.on+.row::before{opacity:0}
  .dsk .lp .row.on{background:var(--you-t);box-shadow:inset 0 0 0 1px rgba(47,109,240,.45)}
  .dsk .lp .row.on p{color:var(--tx)}
  .dsk .lp .empty{margin-top:36px}
  .dsk .lp .rqg{position:relative;border-bottom:0}
  .dsk .lp .row+.rqg::before,.dsk .lp .rqg+.row::before{content:"";position:absolute;left:0;right:0;top:0;border-top:1px solid var(--line)}
  .dsk .lp .rqg+.row::before{left:10px;right:10px}
  .dsk .lp .row:hover+.rqg::before,.dsk .lp .row.on+.rqg::before,.dsk .lp .rqg:has(>.row:hover,>.row.on)::before{opacity:0}

  /* conversation pane: it sits under no status bar, and the list beside it replaces the back button */
  .dsk .scr.np>.chd{padding-top:16px;padding-bottom:14px}
  .dsk .lp~.mp .chd>[data-act=back]{display:none}
  .dsk .chd .ibtn.on{background:var(--you-t);color:var(--you-l)}

  /* nothing picked yet */
  .scr.pick{display:grid;place-items:center;text-align:center;background:radial-gradient(55% 42% at 50% 40%,rgba(47,109,240,.13),transparent 70%),var(--bg)}
  .pick .pk{max-width:440px}
  .pick .pk>svg{width:64px;height:54px;margin-bottom:24px}
  .pick .h2{font-size:38px}
  .pick .lead{margin:12px auto 26px;max-width:360px}
  .pick .two{max-width:360px;margin:0 auto}

  .sp .tkv .f .lkx{font-size:14px}

  /* signed-out and guest flows: brand stage beside the form */
  .dsk.staged{grid-template-columns:minmax(0,1.1fr) minmax(460px,1fr)}
  .stg{display:flex;flex-direction:column;justify-content:space-between;gap:36px;padding:30px clamp(40px,5vw,72px) 44px;background:linear-gradient(var(--bg),rgba(13,14,17,0) 160px),radial-gradient(80% 50% at 100% 6%,rgba(47,109,240,.26),transparent 70%),radial-gradient(70% 45% at 0% 72%,rgba(143,180,255,.09),transparent 72%),var(--bg);border-right:1px solid var(--line);overflow:hidden;min-height:0}
  .stg .duet{margin:0;width:100%;max-width:540px}
  .stg .duet .u p,.stg .duet .t p{font-size:clamp(26px,2.4vw,34px);max-width:none}
  .stg .h1{font-size:clamp(44px,4.4vw,66px)}
  .stg .pts{display:flex;flex-wrap:wrap;gap:10px 24px;margin-top:22px;color:var(--tx2);font-size:14px}
  .stg .pts span{display:flex;align-items:center;gap:8px}
  .stg .pts .ic{color:var(--you-l)}
  .staged .pane .scr:not(.np){--gx:max(44px,calc((100cqw - 440px) / 2));padding-top:36px}
  .staged .pane .top .brand{display:none}
  .staged .pane .top:has(>.brand){justify-content:flex-end}
  .staged .pane .top:not(:has(>:not(.brand,span:empty))){display:none}

  /* landing: hero in two columns */
  .scr.land{padding:28px max(48px,calc((100vw - 1200px) / 2)) 0}
  .land .land-body{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.95fr);grid-template-rows:auto 1fr auto auto auto 1fr auto;column-gap:clamp(48px,7vw,120px);min-height:100%}
  .land .top{grid-column:1/-1}
  .land .duet{grid-column:2;grid-row:2/7;align-self:center;margin:28px 0}
  .land .duet .u,.land .duet .t{padding:26px 30px 36px}
  .land .duet .t{padding-top:40px}
  .land .duet .u p,.land .duet .t p{font-size:clamp(28px,2.6vw,38px);max-width:none}
  .land .duet .swap{right:30px;width:54px;height:54px;margin-top:-27px}
  .land .h1{grid-column:1;grid-row:3;margin-top:0;font-size:clamp(52px,4.7vw,76px)}
  .land .lead{grid-column:1;grid-row:4;margin-top:20px;max-width:440px;font-size:19px}
  .land .push{display:none}
  .land .cta{grid-column:1;grid-row:5;margin-top:34px;padding:0;grid-template-columns:auto auto;justify-content:start;gap:12px}
  .land .cta .btn{width:auto;padding:0 26px}
  .land .cta .fine{grid-column:1/-1;text-align:left;margin-top:6px}
  .lsteps{grid-column:1/-1;grid-row:7;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px;margin-top:40px;padding:28px 0 40px;border-top:1px solid var(--line)}
  .lsteps .n{display:inline-block;font:500 12px/1 var(--mono);color:var(--you-l);background:var(--you-t);border-radius:5px;padding:6px 7px;margin-bottom:14px}
  .lsteps b{display:block;font:700 19px/1.2 var(--disp);letter-spacing:-.01em}
  .lsteps p{margin-top:7px;max-width:320px;color:var(--tx2);font-size:14px;line-height:1.5}
}
@media (min-width:900px) and (max-height:700px){.stg .duet{display:none}}