:root{
  --bg:#0e1116; --surface:#161b22; --surface-2:#1c2230; --border:#2a313c;
  --ink:#e7ebf2; --ink-soft:#9aa4b2; --ink-dim:#6b7480;
  --accent:#6ea8fe; --accent-ink:#0e1116;
  --trap:#e5686a; --etip:#e0ad4c; --dissent:#b794f6; --hypo:#33bda2; --abox:#5cb571; --plain:#c8a07e; --case:#8b95a3;
  --good:#3fb769; --bad:#e5686a;
  --radius:16px; --maxfeed:600px; --railw:208px;
  --mono:ui-monospace,"SF Mono",Menlo,Consolas,monospace;
  --serif:"Iowan Old Style","Palatino Linotype",Georgia,serif;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}
*{box-sizing:border-box}
html,body{margin:0}
body{
  background:var(--bg); color:var(--ink); font-family:var(--sans);
  font-size:15px; line-height:1.5; -webkit-font-smoothing:antialiased;
  padding-bottom:env(safe-area-inset-bottom);
}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;cursor:pointer;background:none;border:none}

/* ---------- shell / layout ---------- */
.shell{display:grid;grid-template-columns:1fr;min-height:100vh;justify-content:center}
.rail,.sidebar{display:none}
.center{border-inline:1px solid var(--border);min-width:0;width:100%;max-width:var(--maxfeed);margin-inline:auto}

@media (min-width:900px){
  .shell{grid-template-columns:var(--railw) minmax(0,var(--maxfeed));justify-content:center;gap:0}
  .rail{display:flex}
  .center{max-width:none}
  .topbar .brand--mobile{display:none}
}
@media (min-width:1200px){
  .shell{grid-template-columns:var(--railw) minmax(0,var(--maxfeed)) 320px}
  .sidebar{display:block}
}

/* ---------- left rail ---------- */
.rail{flex-direction:column;gap:4px;padding:14px 10px;position:sticky;top:0;height:100vh}
.brand{display:flex;align-items:center;gap:8px;font-size:17px;font-weight:700;letter-spacing:-.02em;padding:4px 6px}
.brand b{color:var(--accent);font-weight:800}
.rail .brand{min-width:0;font-size:15px;overflow:hidden}
.rail .brand span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.rail-toggle{margin-top:auto;display:flex;align-items:center;gap:10px;width:auto;padding:9px 10px;border-radius:10px;color:var(--ink-soft);font-size:14px;font-weight:600}
.rail-toggle:hover{background:var(--surface-2);color:var(--ink)}
.rail-toggle svg{width:18px;height:18px;flex:none;transition:transform .2s}
.rail-nav{display:flex;flex-direction:column;gap:2px;margin-top:6px}
.rail-nav a{position:relative;display:flex;align-items:center;gap:12px;padding:10px 12px;border-radius:12px;font-size:15px;color:var(--ink)}
.rail-nav a svg{width:21px;height:21px;flex:none}
.rail-nav a:hover{background:var(--surface-2)}
.rail-nav a.active{font-weight:700}
.rail-nav a.active svg{color:var(--accent)}
.rail-nav .pill{margin-left:auto;background:var(--accent);color:var(--accent-ink);font-size:11px;font-weight:800;border-radius:999px;padding:1px 7px}
.rail-note{margin-top:8px;font-size:11px;color:var(--ink-dim);padding:0 10px;line-height:1.4}

/* collapsed rail */
body[data-rail="collapsed"]{--railw:64px}
body[data-rail="collapsed"] .rail{padding:14px 8px}
body[data-rail="collapsed"] .rail .brand{padding:2px;justify-content:center}
body[data-rail="collapsed"] .rail .brand span{display:none}
body[data-rail="collapsed"] .rail-toggle{justify-content:center;padding:9px 0}
body[data-rail="collapsed"] .rail-toggle .rt-label{display:none}
body[data-rail="collapsed"] .rail-toggle svg{transform:rotate(180deg)}
body[data-rail="collapsed"] .rail-nav a{justify-content:center;gap:0;padding:11px 0}
body[data-rail="collapsed"] .rail-nav a span{display:none}
body[data-rail="collapsed"] .rail-nav .pill{display:none}
body[data-rail="collapsed"] .rail-note{display:none}

/* ---------- topbar ---------- */
.topbar{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:blur(8px);border-bottom:1px solid var(--border)}
.brand--mobile{padding:12px 14px 8px;font-size:18px}
.feed-controls{padding:0 10px 8px}
/* hide feed controls when not on feed */
body[data-view="quiz"] .feed-controls,
body[data-view="saved"] .feed-controls,
body[data-view="progress"] .feed-controls{display:none}
body[data-view="quiz"] .topbar,
body[data-view="saved"] .topbar,
body[data-view="progress"] .topbar{padding-bottom:0}

.segmented{display:flex;gap:4px;background:var(--surface);border:1px solid var(--border);border-radius:999px;padding:3px;width:100%;max-width:100%}
.segmented button{flex:1;text-align:center;padding:6px 16px;border-radius:999px;font-size:14px;font-weight:600;color:var(--ink-soft);white-space:nowrap}
.segmented button.active{background:var(--accent);color:var(--accent-ink)}

/* ---------- surfaces ---------- */
.surface{display:block}
.surface[hidden]{display:none}

/* ---------- post ---------- */
.post{padding:16px;border-bottom:1px solid var(--border);animation:fade .25s ease}
@keyframes fade{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
.post-head{display:flex;align-items:center;gap:10px}
.avatar{width:42px;height:42px;border-radius:50%;flex:none;display:grid;place-items:center;color:#fff;font-weight:700;font-size:15px;letter-spacing:.02em;overflow:hidden;position:relative}
.avatar img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}
.avatar--sm{width:30px;height:30px;font-size:12px}
.who{min-width:0}
.who .name{font-weight:700;letter-spacing:-.01em}
.who .meta{color:var(--ink-soft);font-size:13px;display:flex;gap:6px;align-items:center;flex-wrap:wrap}
.role-pill{font-family:var(--mono);text-transform:uppercase;font-size:9.5px;letter-spacing:.06em;padding:2px 6px;border-radius:5px;background:var(--surface-2);color:var(--ink-soft);border:1px solid var(--border)}
.rule-chip{display:inline-flex;align-items:center;gap:6px;margin:10px 0 8px;font-family:var(--mono);font-size:11px;text-transform:uppercase;letter-spacing:.04em;color:var(--accent);background:color-mix(in srgb,var(--accent) 12%,transparent);border:1px solid color-mix(in srgb,var(--accent) 30%,transparent);padding:3px 9px;border-radius:7px}
.post-body{font-size:15.5px;line-height:1.55}
.post-body.lead{font-family:var(--serif);font-size:17px;font-style:italic;line-height:1.5}

/* thread / carousel */
.thread{margin-top:10px}
.thread-strip{display:flex;gap:10px;overflow-x:auto;scroll-snap-type:x mandatory;scrollbar-width:none;padding-bottom:4px;margin:0 -2px}
.thread-strip::-webkit-scrollbar{display:none}
.thread-card{scroll-snap-align:start;flex:0 0 84%;background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:14px}
.thread-card h4{margin:0 0 6px;font-family:var(--mono);font-size:11px;text-transform:uppercase;letter-spacing:.05em;color:var(--accent)}
.thread-card p{margin:0;font-size:15px}
.dots{display:flex;gap:6px;justify-content:center;margin-top:8px}
.dots i{width:6px;height:6px;border-radius:50%;background:var(--border);transition:.2s}
.dots i.on{background:var(--accent);width:18px;border-radius:999px}

/* actions */
.actions{display:flex;gap:6px;margin-top:14px;flex-wrap:wrap}
@media (min-width:900px){ .actions{justify-content:space-between;gap:4px} }
.act{display:inline-flex;align-items:center;gap:6px;color:var(--ink-soft);font-size:13px;padding:6px 10px;border-radius:999px;transition:.15s}
.act:hover{background:var(--surface-2)}
.act svg{width:17px;height:17px}
.act.on{color:var(--accent)}
.act.on.gotit{color:var(--good)}
.act.test{color:var(--etip)}
.act .n{font-variant-numeric:tabular-nums}

/* comments / footnotes */
.footnotes{margin-top:12px;border-top:1px dashed var(--border);padding-top:10px;display:none}
.footnotes.open{display:block}
.cmt{display:flex;gap:9px;padding:8px 0}
.cmt.reply{margin-left:30px;padding-top:4px}
.cmt-body{min-width:0}
.cmt .name{font-weight:600;font-size:13.5px}
.cmt .kind{font-family:var(--mono);font-size:9px;text-transform:uppercase;letter-spacing:.05em;padding:1px 5px;border-radius:4px;margin-left:6px;vertical-align:middle}
.cmt p{margin:2px 0 0;font-size:14px;color:var(--ink)}
.cmt.k-trap{border-left:3px solid var(--trap);padding-left:10px}
.cmt.k-trap .kind{background:color-mix(in srgb,var(--trap) 20%,transparent);color:var(--trap)}
.cmt.k-etip{border-left:3px solid var(--etip);padding-left:10px}
.cmt.k-etip .kind{background:color-mix(in srgb,var(--etip) 20%,transparent);color:var(--etip)}
.cmt.k-note .kind{background:var(--surface-2);color:var(--ink-soft)}
.cmt.k-dissent{border-left:3px solid var(--dissent);padding-left:10px}
.cmt.k-dissent .kind{background:color-mix(in srgb,var(--dissent) 20%,transparent);color:var(--dissent)}
.cmt.k-hypo .kind{background:color-mix(in srgb,var(--hypo) 20%,transparent);color:var(--hypo)}
.cmt.k-abox .kind{background:color-mix(in srgb,var(--abox) 20%,transparent);color:var(--abox)}
.cmt.k-plain .kind{background:color-mix(in srgb,var(--plain) 20%,transparent);color:var(--plain)}
.cmt.k-case{color:var(--ink-soft)}
.cmt.k-case .kind{background:var(--surface-2);color:var(--case)}
.cmt.k-case p{font-family:var(--mono);font-size:12.5px;color:var(--ink-soft)}
.cmt.k-banter p{color:var(--ink-soft)}

/* post flash (deep-link) */
.post.flash{animation:flash 1.6s ease}
@keyframes flash{0%,100%{background:transparent}20%,50%{background:color-mix(in srgb,var(--accent) 14%,transparent)}}

/* terminus / empty */
.terminus,.empty{padding:34px 20px;text-align:center;color:var(--ink-soft)}
.terminus b,.empty b{color:var(--ink);display:block;font-size:17px;margin-bottom:6px}
.btn{display:inline-block;margin-top:12px;background:var(--accent);color:var(--accent-ink);font-weight:700;padding:10px 20px;border-radius:999px}
.btn.ghost{background:none;border:1px solid var(--border);color:var(--ink)}

/* ---------- quiz ---------- */
.quiz-head{padding:16px;border-bottom:1px solid var(--border);display:flex;justify-content:space-between;align-items:baseline;gap:10px}
.quiz-head h2{margin:0;font-size:18px}
.quiz-score{font-family:var(--mono);font-size:12px;color:var(--ink-soft)}
.quiz-score b{color:var(--etip)}
.qcard{padding:18px 16px}
.qcount{font-family:var(--mono);font-size:11px;letter-spacing:.05em;color:var(--ink-dim);text-transform:uppercase}
.qchip{margin:8px 0 0}
.stem{font-size:17px;font-weight:600;margin:8px 0 16px;line-height:1.45}
.opts{display:flex;flex-direction:column;gap:10px}
.opt{text-align:left;border:1px solid var(--border);background:var(--surface);border-radius:12px;padding:13px 15px;font-size:15px;display:flex;gap:10px;align-items:flex-start;transition:.12s}
.opt:hover:not(:disabled){border-color:var(--accent)}
.opt .tick{width:20px;height:20px;flex:none;border:1.5px solid var(--ink-dim);border-radius:50%;display:grid;place-items:center;font-size:12px;margin-top:1px}
.opt.correct{border-color:var(--good);background:color-mix(in srgb,var(--good) 14%,transparent)}
.opt.correct .tick{border-color:var(--good);background:var(--good);color:#fff}
.opt.wrong{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 12%,transparent)}
.opt.wrong .tick{border-color:var(--bad);background:var(--bad);color:#fff}
.opt:disabled{cursor:default}
.explain{margin-top:16px;background:var(--surface);border:1px solid var(--border);border-left:3px solid var(--accent);border-radius:10px;padding:13px 15px;font-size:14.5px;animation:fade .2s}
.explain .trap{color:var(--trap);margin-top:8px;font-size:13.5px}
.qnav{display:flex;gap:10px;margin-top:16px;flex-wrap:wrap}

/* ---------- progress ---------- */
.dash{padding:18px 16px}
.dash h2{margin:0 0 14px;font-size:19px}
.stat{margin-bottom:16px}
.stat .lab{display:flex;justify-content:space-between;font-size:14px;margin-bottom:6px}
.stat .lab b{font-variant-numeric:tabular-nums}
.bar{height:9px;background:var(--surface-2);border-radius:999px;overflow:hidden}
.bar i{display:block;height:100%;background:var(--accent);border-radius:999px;transition:width .4s}
.bar.good i{background:var(--good)}
.bar.etip i{background:var(--etip)}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:6px}
.kpi{background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:14px}
.kpi .v{font-size:26px;font-weight:800;line-height:1}
.kpi .k{color:var(--ink-soft);font-size:12px;margin-top:4px}
.reset{margin-top:22px}
.reset button{color:var(--ink-dim);font-size:12px;text-decoration:underline}

/* ---------- sidebar widgets ---------- */
.sidebar{padding:16px 14px;position:sticky;top:0;height:100vh;overflow:auto}
.widget{background:var(--surface);border:1px solid var(--border);border-radius:14px;padding:14px;margin-bottom:14px}
.widget h3{margin:0 0 10px;font-size:15px}
.widget .row{display:flex;align-items:center;gap:9px;padding:6px 0;width:100%;text-align:left}
.widget .row:hover .name{color:var(--accent)}
.trend{display:block;padding:7px 0;border-bottom:1px solid var(--border)}
.trend:last-child{border-bottom:none}
.trend .t{font-family:var(--mono);font-size:10px;color:var(--ink-dim);text-transform:uppercase}
.trend .r{font-weight:600;font-size:14px}
.mini-stat{font-size:13px;color:var(--ink-soft);margin-bottom:8px}
.side-legal{font-size:11px;color:var(--ink-dim);line-height:1.4;padding:0 4px}

/* ---------- bottom tab bar (mobile) ---------- */
.tabbar{position:fixed;bottom:0;left:0;right:0;z-index:40;display:flex;background:color-mix(in srgb,var(--bg) 94%,transparent);backdrop-filter:blur(10px);border-top:1px solid var(--border);padding-bottom:env(safe-area-inset-bottom)}
.tabbar a{flex:1;display:flex;flex-direction:column;align-items:center;gap:2px;padding:9px 0 8px;color:var(--ink-soft);font-size:10px;position:relative}
.tabbar a.active{color:var(--accent)}
.tabbar a svg{width:23px;height:23px}
.tabbar a .dot{position:absolute;top:6px;right:calc(50% - 16px);width:7px;height:7px;background:var(--accent);border-radius:50%}
@media (min-width:900px){ .tabbar{display:none} body{padding-bottom:0} }
@media (max-width:899px){ body{padding-bottom:64px} }

/* ---------- account switcher (each subject = an account) ---------- */
.brand--mobile{display:none}                       /* mobile header identity is now the account chip */
.topbar-row{display:flex;align-items:center;gap:8px;padding:8px 12px 6px}
@media (min-width:900px){ .topbar-row{display:none} }   /* desktop: account chip lives in the rail */
.acct-chip{display:flex;align-items:center;gap:9px;width:100%;text-align:left;padding:8px 10px;border-radius:12px;color:var(--ink);background:var(--surface);border:1px solid var(--border);transition:.15s}
.acct-chip:hover{background:var(--surface-2)}
.acct-chip--rail{margin:2px 0 8px}
.acct-badge{width:30px;height:30px;border-radius:9px;flex:none;display:grid;place-items:center;font-size:16px}
.acct-meta{min-width:0;display:flex;flex-direction:column;line-height:1.2}
.acct-name{font-weight:700;font-size:13.5px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.acct-tag{font-size:11px;color:var(--ink-soft);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.acct-caret{width:16px;height:16px;color:var(--ink-soft);flex:none;margin-left:auto}
body[data-rail="collapsed"] .acct-chip{justify-content:center;padding:8px 0}
body[data-rail="collapsed"] .acct-chip .acct-meta,
body[data-rail="collapsed"] .acct-chip .acct-caret{display:none}

.acct-menu{position:fixed;inset:0;z-index:60;display:none;background:rgba(0,0,0,.55);backdrop-filter:blur(2px);align-items:flex-end;justify-content:center}
.acct-menu.open{display:flex;animation:fade .2s ease}
.acct-sheet{background:var(--surface);border:1px solid var(--border);border-radius:18px 18px 0 0;width:100%;max-width:520px;padding:14px 12px calc(16px + env(safe-area-inset-bottom));box-shadow:0 -10px 44px rgba(0,0,0,.55)}
.acct-sheet-title{font-size:11px;text-transform:uppercase;letter-spacing:.06em;color:var(--ink-soft);padding:2px 8px 10px}
.acct-item{display:flex;align-items:center;gap:12px;width:100%;text-align:left;padding:12px 10px;border-radius:14px;color:var(--ink);transition:.12s}
.acct-item:hover{background:var(--surface-2)}
.acct-item.on{background:color-mix(in srgb,var(--accent) 14%,transparent)}
.acct-item .acct-badge{width:42px;height:42px;border-radius:13px;font-size:22px}
.acct-item .acct-name{font-size:15px;white-space:normal}
.acct-blurb{font-size:12.5px;color:var(--ink-soft);white-space:normal;line-height:1.3;margin-top:2px}
.acct-check{margin-left:auto;color:var(--accent);font-weight:800;font-size:18px}
@media (min-width:640px){ .acct-menu{align-items:center} .acct-sheet{border-radius:18px} }