:root{
  --bg:#0b0f14; --panel:#11161e; --text:#e6eef8; --muted:#9fb3c8; --gold:#CDA75C;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--text);font-family:system-ui,-apple-system,Segoe UI,Roboto,Inter,Arial}
a{color:inherit;text-decoration:none}

/* Left sidebar (slim, no logo/title/home/books; single Coil Tech) */
.sidebar{position:fixed;top:0;left:0;width:280px;height:100vh;background:linear-gradient(180deg,#0c1118 0%,#0a0f15 100%);border-right:1px solid #1b2431;padding:12px;overflow-y:auto}
.nav-group{margin:10px 0}
.nav-heading{color:var(--muted);font-size:.85rem;letter-spacing:.06em;padding:8px 8px;text-transform:uppercase}
.nav-list{display:grid;gap:6px;padding:4px 6px}
.nav-item{display:flex;align-items:center;gap:10px;padding:10px 12px;border:1px solid #1f2a39;border-radius:12px;background:#0d131b;color:var(--text);transition:border-color .2s ease,box-shadow .2s ease,transform .04s ease}
.nav-item .ico{color:var(--gold);width:1.2rem;display:inline-flex;justify-content:center}
.nav-item:hover{border-color:var(--gold);box-shadow:0 0 0 2px rgba(205,167,92,.15);transform:translateY(-1px)}
.nav-item.active{border-color:var(--gold);box-shadow:0 0 0 2px rgba(205,167,92,.18)}

/* Main column */
.main{margin-left:280px;padding:18px 16px 32px}

/* Header with emblem centered and symbol rails aligned left/right */
.header-hero{margin-top:12px;margin-bottom:6px}
.header-row{display:flex;align-items:center;justify-content:center;gap:20px}
.header-rail{display:flex;gap:12px;color:var(--gold);font-size:2rem;white-space:nowrap}
.header-emblem{width:130px;height:auto}
@media (max-width: 720px){
  .header-rail{font-size:1.4rem;gap:.6rem}
  .header-emblem{width:110px}
}
h1{margin:8px 0 4px;text-align:center;font-size:1.6rem;letter-spacing:.6px}
.small{text-align:center;color:var(--muted)}
.status{text-align:center;color:var(--muted);margin-top:6px}

/* Chat widget fills the content area */
.chat-container{display:flex;flex-direction:column;height:calc(100vh - 240px);border:1px solid #1f2a39;border-radius:12px;background:#0e151f;margin-top:16px}
.chat-messages{flex:1;overflow-y:auto;padding:12px}
.msg{margin-bottom:10px;line-height:1.35}
.msg .who{opacity:.85;margin-right:6px}
.chat-input{display:flex;border-top:1px solid #1f2a39}
.chat-input input{flex:1;padding:12px;border:0;outline:0;background:transparent;color:var(--text)}
.chat-input button{padding:0 16px;background:var(--gold);color:#000;border:0;cursor:pointer;border-left:1px solid #1f2a39}

/* Footer */
.main-footer{margin-left:280px;border-top:1px solid #1b2431;padding:16px;color:var(--muted);text-align:center}