:root{
  --bg:#F1F4F3; --surface:#FFFFFF; --ink:#14212E; --muted:#5A6B78; --line:#D5DDDA;
  --accent:#0F6B5C; --accent-ink:#FFFFFF; --accent-soft:#DCEFEA;
  --good:#1B7F4B; --good-soft:#DDF1E5; --bad:#B3392F; --bad-soft:#F7E0DD; --flag:#9A6B00; --flag-soft:#F6EACB;
  --display:"Bricolage Grotesque","Segoe UI",system-ui,sans-serif;
  --body:"Source Sans 3","Segoe UI",system-ui,sans-serif;
  --mono:"IBM Plex Mono",ui-monospace,Menlo,monospace;
}
@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
    color-scheme:dark;
    --bg:#0F1719; --surface:#182226; --ink:#E6EDEB; --muted:#93A5AB; --line:#2B393E;
    --accent:#3FB59E; --accent-ink:#06201A; --accent-soft:#17352F;
    --good:#4CC583; --good-soft:#163526; --bad:#F0837A; --bad-soft:#3B1F1D; --flag:#E2B24A; --flag-soft:#3A2F14;
  }
}
:root[data-theme="dark"]{
  color-scheme:dark;
  --bg:#0F1719; --surface:#182226; --ink:#E6EDEB; --muted:#93A5AB; --line:#2B393E;
  --accent:#3FB59E; --accent-ink:#06201A; --accent-soft:#17352F;
  --good:#4CC583; --good-soft:#163526; --bad:#F0837A; --bad-soft:#3B1F1D; --flag:#E2B24A; --flag-soft:#3A2F14;
}
*{box-sizing:border-box}
body{background:var(--bg);color:var(--ink);font-family:var(--body);font-size:16px;line-height:1.5;padding-inline:16px;padding-block:20px 48px}
.wrap{max-width:720px;margin-inline:auto;display:flex;flex-direction:column;gap:20px}
/* The drill keeps a reading measure — a question stem is prose and belongs in a narrow
   column whatever the screen. The data pages are tables, and on a laptop or desktop a
   720px column wastes half the width and squeezes six columns for no reason. */
@media (min-width:920px){ .wrap.wide{max-width:1080px} }
@media (min-width:1400px){ .wrap.wide{max-width:1200px} }
h1,h2,h3{font-family:var(--display);margin:0;text-wrap:balance;line-height:1.15}
h1{font-size:clamp(1.9rem,6vw,2.6rem);letter-spacing:-.02em}
h2{font-size:1.25rem}
.eyebrow{font-size:.75rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);font-weight:600}
.sub{color:var(--muted);margin:6px 0 0;max-width:60ch}
.panel{background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:18px;display:flex;flex-direction:column;gap:14px}
.choices{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:10px}
.choice{appearance:none;text-align:left;font:inherit;color:var(--ink);background:var(--bg);border:1.5px solid var(--line);border-radius:8px;padding:12px 14px;cursor:pointer;display:flex;flex-direction:column;gap:2px}
.choice b{font-weight:600}
.choice span{font-size:.85rem;color:var(--muted)}
.choice[aria-pressed="true"]{border-color:var(--accent);background:var(--accent-soft)}
.choice:focus-visible,.btn:focus-visible,.opt:focus-visible{outline:3px solid var(--accent);outline-offset:2px}
.btn{appearance:none;font:inherit;font-weight:600;border:0;border-radius:8px;padding:12px 20px;cursor:pointer;background:var(--accent);color:var(--accent-ink);text-decoration:none;display:inline-block;text-align:center}
.btn.ghost{background:transparent;color:var(--ink);border:1.5px solid var(--line)}
.btn[disabled]{opacity:.45;cursor:default}
.row{display:flex;flex-wrap:wrap;gap:10px;align-items:center}
.spread{justify-content:space-between}
.bar{height:6px;background:var(--line);border-radius:3px;overflow:hidden}
.bar>i{display:block;height:100%;background:var(--accent);width:0;transition:width .25s}
.meta{display:flex;flex-wrap:wrap;gap:8px 14px;align-items:center;font-size:.85rem;color:var(--muted)}
.timer{font-family:var(--mono);font-variant-numeric:tabular-nums;color:var(--ink)}
.tag{font-size:.72rem;letter-spacing:.06em;text-transform:uppercase;font-weight:600;padding:3px 8px;border-radius:5px;background:var(--accent-soft);color:var(--accent)}
.tag.pa{background:var(--flag-soft);color:var(--flag)}
.stem{font-size:1.15rem;line-height:1.45;margin:0;max-width:62ch}
.opts{display:flex;flex-direction:column;gap:10px;margin:0;padding:0;list-style:none}
.opt{appearance:none;width:100%;text-align:left;font:inherit;color:var(--ink);background:var(--surface);border:1.5px solid var(--line);border-radius:8px;padding:12px 14px;cursor:pointer;display:flex;gap:12px;align-items:flex-start}
.opt .k{font-family:var(--mono);font-weight:500;color:var(--muted);min-width:1.2em}
.opt[aria-pressed="true"]{border-color:var(--accent);background:var(--accent-soft)}
.opt.right{border-color:var(--good);background:var(--good-soft)}
.opt.wrong{border-color:var(--bad);background:var(--bad-soft)}
.opt[disabled]{cursor:default}
.why{border-left:4px solid var(--accent);background:var(--accent-soft);padding:12px 14px;border-radius:0 8px 8px 0;font-size:.98rem}
.why.no{border-color:var(--bad);background:var(--bad-soft)}
.why.yes{border-color:var(--good);background:var(--good-soft)}
.why b{display:block;margin-bottom:2px}
.score{font-family:var(--display);font-size:3.2rem;line-height:1;letter-spacing:-.02em}
.score small{font-size:1.2rem;color:var(--muted);font-family:var(--body)}
.secrow{display:grid;grid-template-columns:120px 1fr 56px;gap:10px;align-items:center;font-size:.92rem}
.secrow .n{font-variant-numeric:tabular-nums;text-align:right;color:var(--muted)}
.rev{display:flex;flex-direction:column;gap:12px}
.rev details{border:1px solid var(--line);border-radius:8px;padding:10px 12px;background:var(--bg)}
.rev summary{cursor:pointer;font-weight:600}
.rev p{margin:8px 0 0}
.note{font-size:.85rem;color:var(--muted);max-width:64ch}
.tt{position:absolute;top:12px;right:12px}
@media (max-width:420px){.secrow{grid-template-columns:90px 1fr 48px}}
@media (prefers-reduced-motion:reduce){.bar>i{transition:none}}

/* ---------- added for the hosted version: nav, sign-in, history, topics, admin ---------- */
a{color:var(--accent)}
.nav{display:flex;flex-wrap:wrap;gap:8px 16px;align-items:baseline;justify-content:space-between;
  border-bottom:1px solid var(--line);padding-bottom:12px}
.nav .brand{font-family:var(--display);font-weight:700;font-size:1.05rem;letter-spacing:-.01em;
  color:var(--ink);text-decoration:none}
.nav ul{display:flex;flex-wrap:wrap;gap:4px;margin:0;padding:0;list-style:none;align-items:center}
.nav a.link{display:inline-block;padding:6px 10px;border-radius:6px;text-decoration:none;
  color:var(--muted);font-weight:600;font-size:.9rem}
.nav a.link:hover{background:var(--accent-soft);color:var(--accent)}
.nav a.link[aria-current="page"]{background:var(--accent-soft);color:var(--accent)}
.nav .who{font-size:.82rem;color:var(--muted);font-variant-numeric:tabular-nums}
.nav form{display:inline}
.nav button.out{appearance:none;background:none;border:0;font:inherit;font-size:.9rem;font-weight:600;
  color:var(--muted);cursor:pointer;padding:6px 10px;border-radius:6px}
.nav button.out:hover{background:var(--bad-soft);color:var(--bad)}

.center{max-width:420px;margin-inline:auto}
.field{display:flex;flex-direction:column;gap:6px}
.field label{font-weight:600;font-size:.9rem}
.field input{appearance:none;font:inherit;color:var(--ink);background:var(--bg);
  border:1.5px solid var(--line);border-radius:8px;padding:12px 14px;width:100%}
.field input:focus-visible{outline:3px solid var(--accent);outline-offset:2px;border-color:var(--accent)}
.field input.code{font-family:var(--mono);font-size:1.6rem;letter-spacing:.3em;text-align:center}
.alert{border-left:4px solid var(--bad);background:var(--bad-soft);color:var(--ink);
  padding:12px 14px;border-radius:0 8px 8px 0;font-size:.95rem}
.sent{border-left:4px solid var(--good);background:var(--good-soft);
  padding:12px 14px;border-radius:0 8px 8px 0;font-size:.95rem}

.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(112px,1fr));gap:12px}
.stat{background:var(--bg);border:1px solid var(--line);border-radius:8px;padding:12px 14px}
.stat b{display:block;font-family:var(--display);font-size:1.7rem;line-height:1.1;
  letter-spacing:-.02em;font-weight:700;font-variant-numeric:tabular-nums}
.stat span{font-size:.78rem;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);font-weight:600}

.tbl{width:100%;border-collapse:collapse;font-size:.92rem}
.tbl th{text-align:left;font-size:.75rem;letter-spacing:.08em;text-transform:uppercase;
  color:var(--muted);font-weight:600;padding:0 10px 8px 0;border-bottom:1px solid var(--line);
  white-space:nowrap}
.tbl td{padding:10px 10px 10px 0;border-bottom:1px solid var(--line);vertical-align:middle}
.tbl tr:last-child td{border-bottom:0}
.tbl .num{text-align:right;font-variant-numeric:tabular-nums;white-space:nowrap}
.scroll{overflow-x:auto}
.pill{display:inline-block;font-size:.74rem;font-weight:600;padding:3px 8px;border-radius:5px;
  background:var(--accent-soft);color:var(--accent);white-space:nowrap}
.pill.warn{background:var(--bad-soft);color:var(--bad)}
.pill.mid{background:var(--flag-soft);color:var(--flag)}
.pill.ok{background:var(--good-soft);color:var(--good)}
.minibar{min-width:70px;height:6px;background:var(--line);border-radius:3px;overflow:hidden}
.minibar>i{display:block;height:100%;background:var(--accent);border-radius:3px}
.minibar.warn>i{background:var(--bad)}
.minibar.mid>i{background:var(--flag)}
.empty{color:var(--muted);font-size:.95rem;margin:0}
.person{border:1px solid var(--line);border-radius:10px;padding:16px;background:var(--bg);
  display:flex;flex-direction:column;gap:14px}
.person h3{font-size:1.05rem}
@media (max-width:480px){
  .nav{flex-direction:column;align-items:flex-start;gap:6px}
  .stat b{font-size:1.45rem}
}

#app{display:flex;flex-direction:column;gap:20px}
.saving{font-size:.85rem;color:var(--muted)}
.saving.bad{color:var(--bad)}

/* ---------- phone: tables stack into cards ----------
   She revises mostly on a phone, and a six-column table inside a horizontally
   scrolling box is close to unusable there — the last columns are simply never seen.
   Below 560px each row becomes a card and each cell carries its own label. */
@media (max-width:560px){
  .nav .who{display:none}
  .scroll{overflow-x:visible}
  .tbl thead{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;
    clip:rect(0 0 0 0);white-space:nowrap;border:0}
  .tbl,.tbl tbody,.tbl tr,.tbl td{display:block;width:100%}
  .tbl tr{border:1px solid var(--line);border-radius:8px;padding:8px 12px;margin-bottom:10px;
    background:var(--surface)}
  .tbl tr:last-child{margin-bottom:0}
  .tbl td{border:0;padding:5px 0;display:flex;gap:12px;align-items:center;
    justify-content:space-between;text-align:right}
  .tbl td::before{content:attr(data-label);flex:0 0 auto;text-align:left;
    font-size:.72rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);font-weight:600}
  .tbl td:first-child{border-bottom:1px solid var(--line);margin-bottom:4px;padding-bottom:8px;
    font-weight:600;font-size:1rem}
  .tbl td .minibar{flex:1 1 auto;max-width:55%}
  .tbl td.barcell{display:none}
}