:root{
  --bg:#f4f6f8; --panel:#fff; --ink:#1d2733; --muted:#6b7a8c; --line:#dde3ea;
  --dark:#3e4a5c; --slate:#5a6e82; --accent:#0070c0; --accent-ink:#fff;
  --sel:#dff0d8; --warn-bg:#fff4d6; --warn-line:#e0a800; --warn-ink:#6b4e00;
  --t0:#ffc7ce; --t3:#ffd6b3; --t2:#fff0b3; --t1:#d6f0d6; --danger:#b02a37;
}
@media (prefers-color-scheme: dark){
  :root{ --bg:#151a21; --panel:#1d242e; --ink:#e8edf3; --muted:#94a3b4; --line:#2c3643;
    --sel:#24402a; --warn-bg:#3a3116; --warn-line:#a37f00; --warn-ink:#f0d68a;
    --t0:#5c2229; --t3:#5c3a1c; --t2:#4d431a; --t1:#22401f; }
}
*{box-sizing:border-box}
body{margin:0;font:15px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;background:var(--bg);color:var(--ink)}
.wrap{max-width:960px;margin:0 auto;padding:0 16px 64px}
header.bar{background:var(--dark);color:#fff;padding:14px 16px}
header.bar .inner{max-width:960px;margin:0 auto;display:flex;gap:12px;align-items:center;flex-wrap:wrap}
header.bar h1{font-size:17px;margin:0;font-weight:700;letter-spacing:.02em}
header.bar .spacer{flex:1}
nav button{background:transparent;border:1px solid rgba(255,255,255,.35);color:#fff;padding:6px 12px;
  border-radius:6px;cursor:pointer;font-size:13px}
nav button[aria-current="true"]{background:#fff;color:var(--dark);border-color:#fff;font-weight:600}
.mock{background:var(--warn-bg);border-bottom:2px solid var(--warn-line);color:var(--warn-ink);
  padding:10px 16px;font-size:13px;font-weight:600;text-align:center}
.mock strong{text-transform:uppercase;letter-spacing:.04em}
.card{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:22px;margin-top:20px}
.progress{color:var(--muted);font-size:12.5px;text-transform:uppercase;letter-spacing:.06em;margin-bottom:10px}
h2.q{font-size:20px;line-height:1.35;margin:0 0 12px}
p.help{color:var(--muted);font-size:13.5px;margin:0 0 18px}
.opts{border:1px solid var(--line);border-radius:8px;overflow:hidden;margin-bottom:18px}
.opt{display:grid;grid-template-columns:38px 84px 1fr;gap:10px;padding:10px 12px;border-top:1px solid var(--line);
  cursor:pointer;align-items:start}
.opt:first-child{border-top:0}
.opt.src{grid-template-columns:38px 84px 1fr 240px}
.opt:hover{background:rgba(0,112,192,.06)}
.opt[aria-checked="true"]{background:var(--sel)}
.opt .box{width:20px;height:20px;border:2px solid var(--muted);border-radius:4px;display:grid;place-items:center;
  font-size:13px;font-weight:800;color:#127a12}
.opt[aria-checked="true"] .box{border-color:#127a12}
.opt .code{font:12px ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--muted);padding-top:2px}
.opt .cite{font-size:12px;color:var(--muted);font-style:italic}
.grouphdr{background:var(--slate);color:#fff;padding:8px 12px;font-size:13px;font-weight:700;letter-spacing:.03em}
.btn{background:var(--accent);color:var(--accent-ink);border:0;border-radius:7px;padding:11px 20px;
  font-size:15px;font-weight:600;cursor:pointer}
.btn.sec{background:transparent;color:var(--ink);border:1px solid var(--line)}
.btn.danger{background:var(--danger);color:#fff}
.btn:disabled{opacity:.5;cursor:not-allowed}
.row{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
.row.end{justify-content:space-between}
label.f{display:block;font-weight:600;font-size:13.5px;margin:14px 0 6px}
input[type=text],input[type=password],textarea{width:100%;padding:10px 12px;border:1px solid var(--line);
  border-radius:7px;background:var(--panel);color:var(--ink);font:inherit}
textarea{min-height:76px;resize:vertical}
.kv{display:grid;grid-template-columns:minmax(190px,270px) 1fr;gap:2px 16px;margin:2px 0}
.kv>dt{font-weight:600;padding:8px 0;border-bottom:1px dotted var(--line)}
.kv>dd{margin:0;padding:8px 0;border-bottom:1px dotted var(--line)}
.section{background:var(--slate);color:#fff;padding:8px 12px;border-radius:6px;font-weight:700;
  font-size:13px;letter-spacing:.04em;margin:24px 0 10px}
.desc{background:rgba(0,112,192,.07);border:1px solid var(--line);border-radius:8px;padding:14px;font-size:16px}
.tier{display:inline-block;padding:5px 12px;border-radius:6px;font-weight:800}
.tier.T0{background:var(--t0)}.tier.T3{background:var(--t3)}.tier.T2{background:var(--t2)}.tier.T1{background:var(--t1)}
table{width:100%;border-collapse:collapse;font-size:13.5px}
th,td{text-align:left;padding:9px 10px;border-bottom:1px solid var(--line);vertical-align:top}
th{background:rgba(90,110,130,.14);font-size:12px;text-transform:uppercase;letter-spacing:.04em}
.err{background:var(--t0);border:1px solid var(--danger);border-radius:8px;padding:12px 14px;margin:14px 0}
.ok{background:var(--t1);border:1px solid #2e7d32;border-radius:8px;padding:12px 14px;margin:14px 0}
.login{max-width:460px;margin:56px auto}
.muted{color:var(--muted);font-size:13px}
.badge{display:inline-block;font-size:11px;padding:2px 8px;border-radius:99px;background:var(--line);color:var(--ink)}
@media (max-width:640px){
  .opt,.opt.src{grid-template-columns:32px 1fr}
  .opt .code,.opt .cite{display:none}
  .kv{grid-template-columns:1fr}
  .kv>dt{border-bottom:0;padding-bottom:0}
}


/* --- 0.3.1 ---------------------------------------------------------------- */

/* Question and help text carry their own line breaks: enumerations are shown
   one item per line instead of running together in a paragraph. */
.q, .help, .lockmsg { white-space: pre-line; }

/* Landing screen */
.homeopts { display: flex; flex-direction: column; gap: 10px; margin-top: 18px; }
.homeopt {
  display: flex; flex-direction: column; gap: 4px; align-items: flex-start;
  padding: 14px 16px; border: 1px solid var(--line); border-radius: 8px;
  background: transparent; cursor: pointer; text-align: left; font: inherit;
  color: inherit; width: 100%;
}
.homeopt:hover, .homeopt:focus-visible { border-color: var(--dark); background: var(--bg); }
.homeopt strong { font-size: 15px; }

/* An option whose state is settled by an earlier answer. Visibly present and
   visibly not yours to change. */
.opt.locked { opacity: .75; cursor: not-allowed; background: var(--bg); }
.opt.locked .box { border-style: dashed; }
.lockmsg { font-size: 12px; opacity: .8; margin-top: 4px; }

/* Registry rows open the full record */
tr.clickable { cursor: pointer; }
tr.clickable:hover, tr.clickable:focus-visible { background: var(--bg); }

.btn[disabled] { opacity: .5; cursor: not-allowed; }
.mock.warn { background: var(--warn-bg); color: var(--warn-ink); border-color: var(--warn-line); }

/* Summary footer: the standing disclosure required by spec 06 §8. */
.footer {
  margin-top: 26px; padding-top: 14px; border-top: 1px solid var(--line);
  font-size: 12px; line-height: 1.6; color: var(--muted);
}

.appfoot{max-width:860px;margin:24px auto 32px;padding:0 16px;font-size:12px;color:#6b7280;text-align:center}

.steptitle{font-size:12px;font-weight:600;letter-spacing:.06em;text-transform:uppercase;color:#3e4a5c;margin:0 0 6px}