:root{
  --ink:#0A1628; --bridge:#2E7DFF; --muted:#64748B; --line:#E5E7EB;
  --bg:#F7FAFF; --card:#fff;
}
*{box-sizing:border-box}
html,body{margin:0}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  color:var(--ink);background:var(--bg);line-height:1.5}
a{color:var(--bridge);text-decoration:none}
main{max-width:1080px;margin:0 auto;padding:28px 20px 60px}

.topbar{display:flex;align-items:center;gap:22px;background:var(--ink);color:#fff;
  padding:14px 22px;position:sticky;top:0;z-index:5}
.brand{color:#fff;font-weight:800;letter-spacing:-.01em;font-size:18px}
.brand span{color:#9DC0FF;font-weight:600}
.topnav{display:flex;gap:6px;margin-left:8px}
.topnav a{color:#CBD5E1;padding:6px 12px;border-radius:8px;font-weight:600}
.topnav a:hover{background:rgba(255,255,255,.10);color:#fff}

.hero h1{font-size:34px;letter-spacing:-.02em;margin:.2em 0}
.hero p{color:var(--muted);font-size:17px;margin:0 0 8px}

.tiles{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin-top:24px}
.tile{display:block;background:var(--card);border:1px solid var(--line);border-radius:16px;
  padding:22px;transition:transform .12s ease,box-shadow .12s ease;border-top:4px solid var(--accent,#2E7DFF)}
.tile:hover{transform:translateY(-3px);box-shadow:0 12px 30px rgba(10,22,40,.10)}
.tile-mark{width:46px;height:46px;border-radius:12px;background:var(--accent);color:#fff;
  display:grid;place-items:center;font-weight:800;font-size:16px;letter-spacing:.02em}
.tile-name{font-size:20px;font-weight:800;margin-top:14px;color:var(--ink)}
.tile-tag{color:var(--muted);margin-top:2px}

.apphead{display:flex;align-items:center;gap:16px;margin-bottom:18px}
.apphead-mark{width:52px;height:52px;border-radius:14px;background:var(--accent,#2E7DFF);color:#fff;
  display:grid;place-items:center;font-weight:800;font-size:18px}
.apphead h1{margin:0;font-size:26px;letter-spacing:-.01em}
.apphead p{margin:0;color:var(--muted)}
.blank{background:var(--card);border:1px dashed var(--line);border-radius:14px;padding:28px}
.muted{color:var(--muted)}

/* Deep Worker */
.dw{display:grid;grid-template-columns:240px 1fr;gap:16px;min-height:60vh}
.dw-list{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:12px;height:66vh;overflow:auto}
#dw-new{width:100%;padding:9px;border:1px solid var(--line);background:#fff;border-radius:10px;
  font-weight:700;cursor:pointer;color:var(--ink)}
#dw-chats{list-style:none;margin:12px 0 0;padding:0}
#dw-chats li{padding:9px 10px;border-radius:9px;cursor:pointer;font-size:14px;color:var(--ink);
  overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
#dw-chats li:hover{background:#EEF4FF}
#dw-chats li.active{background:#E1ECFF;font-weight:700}
.dw-main{display:flex;flex-direction:column;background:var(--card);border:1px solid var(--line);border-radius:14px}
.dw-thread{flex:1;overflow:auto;padding:18px;height:56vh}
.msg{margin:0 0 14px}
.msg .who{font-size:12px;color:var(--muted);font-weight:700;text-transform:uppercase;letter-spacing:.04em}
.msg .txt{margin-top:3px;padding:10px 12px;border-radius:12px;display:inline-block;max-width:80%}
.msg.user .txt{background:#E1ECFF}
.msg.assistant .txt{background:#F1F5F9}
.pending{color:#B45309;font-weight:600;text-transform:none;letter-spacing:0}
.dw-composer{display:flex;gap:8px;border-top:1px solid var(--line);padding:12px}
#dw-input{flex:1;resize:none;border:1px solid var(--line);border-radius:10px;padding:10px;font:inherit}
.dw-composer button{padding:0 18px;border:0;border-radius:10px;background:var(--bridge);color:#fff;
  font-weight:700;cursor:pointer}

.foot{max-width:1080px;margin:0 auto;padding:20px;color:var(--muted);font-size:13px}
@media(max-width:640px){.dw{grid-template-columns:1fr}.dw-list{height:auto}}