/* ===== OS Exam Trainer — FINAL stylesheet =====
   Base: Candidate 1 "Refined Modern SaaS" (indigo/violet) — the judges' winner.
   Grafts:
     · cand3 — dual-layer glowing score-ring, low-opacity dot-texture body wash,
               glowing progress bar + card accent rails, @supports submitbar fallback.
     · cand2 — DOTTED .opt.missed (three distinct post-submit border SHAPES:
               solid/dashed/dotted, color-blind-safe), optional serif display
               headings, dark-theme text-on-accent overrides, roomier qtext.
     · cand4 — rotating theme-toggle micro-interaction, .opt:focus-within row ring,
               gradient-clipped .pct, .card:hover rail-widen.
   Avoided: cand4's amber=fail mapping (fail stays RED) and overshoot easing.
   Self-contained / file:// safe — system fonts only, no network, no images. */

/* ---------- Design tokens ---------- */
:root{
  /* Brand: indigo / violet */
  --accent:#4f46e5;
  --accent2:#7c3aed;
  --accent-ink:#3730a3;
  --accent-soft:#eef2ff;
  --accent-line:#dfe3ff;

  /* Neutral slate scale */
  --bg:#f6f7fb;
  --bg-grad:radial-gradient(1200px 600px at 80% -10%,#eef0ff 0%,rgba(238,240,255,0) 60%),
            radial-gradient(820px 520px at -6% 2%,#ecfbf5 0%,rgba(236,251,245,0) 55%),
            linear-gradient(180deg,#fafbfe 0%,#f3f5fa 100%);
  --dot:rgba(40,52,120,.05);
  --surface:#ffffff;
  --surface-2:#f8fafc;
  --ink:#0f172a;
  --ink-2:#334155;
  --muted:#64748b;
  --line:#e6e9ef;
  --line-strong:#d6dbe6;

  /* Semantic (referenced inline by app.js: --red/--green/--amber) */
  --green:#15803d;        --green-soft:#dcfce7;  --green-line:#bbf7d0;
  --red:#dc2626;          --red-soft:#fee2e2;    --red-line:#fecaca;
  --amber:#b45309;        --amber-soft:#fef3c7;  --amber-line:#fde68a;
  --sky:#0ea5e9;

  /* Accent glow (cand3) */
  --glow:rgba(79,70,229,.30);

  /* Elevation */
  --r-sm:10px; --r-md:14px; --r-lg:18px;
  --sh-1:0 1px 2px rgba(15,23,42,.06),0 1px 1px rgba(15,23,42,.04);
  --sh-2:0 1px 3px rgba(15,23,42,.07),0 10px 24px -8px rgba(15,23,42,.10);
  --sh-3:0 18px 40px -16px rgba(79,70,229,.28),0 8px 18px -10px rgba(15,23,42,.14);
  --ring:0 0 0 3px rgba(79,70,229,.35);

  /* Optional serif display stack (cand2) — used for hero/section/quiz/result headings */
  --serif:Georgia,"Iowan Old Style","Times New Roman",Cambria,"Noto Serif",ui-serif,serif;

  --header-h:60px;
  --ease:cubic-bezier(.2,.7,.3,1);
}

/* ---------- Dark theme ---------- */
html[data-theme="dark"]{
  --accent:#818cf8;
  --accent2:#a78bfa;
  --accent-ink:#c7d2fe;
  --accent-soft:#1e1b4b;
  --accent-line:#312e81;

  --bg:#0b1120;
  --bg-grad:radial-gradient(1200px 600px at 80% -10%,#1b2347 0%,rgba(27,35,71,0) 60%),
            radial-gradient(820px 520px at -6% 2%,rgba(16,90,80,.30) 0%,rgba(16,90,80,0) 55%),
            linear-gradient(180deg,#0b1120 0%,#0a0f1e 100%);
  --dot:rgba(130,160,255,.06);
  --surface:#111a2e;
  --surface-2:#0e1626;
  --ink:#e8edf7;
  --ink-2:#cbd5e1;
  --muted:#94a3b8;
  --line:#1f2a40;
  --line-strong:#2a3852;

  --green:#4ade80;        --green-soft:#0f2a1c;  --green-line:#1f5135;
  --red:#f87171;          --red-soft:#341013;    --red-line:#5c1d22;
  --amber:#fbbf24;        --amber-soft:#2f230a;  --amber-line:#5a4413;
  --sky:#38bdf8;

  --glow:rgba(129,140,248,.45);

  --sh-1:0 1px 2px rgba(0,0,0,.4);
  --sh-2:0 2px 6px rgba(0,0,0,.45),0 14px 30px -12px rgba(0,0,0,.6);
  --sh-3:0 22px 48px -18px rgba(0,0,0,.7),0 8px 18px -10px rgba(0,0,0,.5);
  --ring:0 0 0 3px rgba(129,140,248,.4);
}

/* ---------- Base ---------- */
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
html,body{margin:0;padding:0}
body{
  font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,
              "Helvetica Neue",Arial,"Apple Color Emoji","Segoe UI Emoji",sans-serif;
  background:var(--bg);
  /* low-opacity pure-CSS dot texture layered over the gradient wash (cand3) */
  background-image:
    radial-gradient(var(--dot) 1px,transparent 1px),
    var(--bg-grad);
  background-size:22px 22px,100% 100%,100% 100%,100% 100%;
  background-attachment:fixed;
  color:var(--ink);
  line-height:1.55;
  min-height:100vh;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
  -webkit-tap-highlight-color:transparent;
  transition:background-color .35s ease,color .35s ease;
}
::selection{background:rgba(124,58,237,.22)}
:focus-visible{outline:none}

/* ---------- Header (frosted, sticky) ---------- */
header{
  position:sticky;top:0;z-index:50;
  background:color-mix(in srgb,var(--surface) 78%,transparent);
  backdrop-filter:saturate(160%) blur(14px);
  -webkit-backdrop-filter:saturate(160%) blur(14px);
  border-bottom:1px solid var(--line);
  box-shadow:0 1px 0 rgba(15,23,42,.02);
}
.head-inner{
  max-width:1080px;margin:0 auto;height:var(--header-h);
  padding:0 20px;display:flex;align-items:center;gap:14px;
}
.brand{
  display:flex;align-items:center;gap:11px;cursor:pointer;
  font-weight:800;font-size:1.06rem;letter-spacing:-.01em;color:var(--ink);
}
.brand .logo{
  width:34px;height:34px;border-radius:10px;flex:none;
  background:linear-gradient(135deg,var(--accent),var(--accent2));
  display:grid;place-items:center;font-size:1.05rem;
  box-shadow:0 4px 12px -3px var(--glow),inset 0 1px 0 rgba(255,255,255,.3);
}
.brand small{
  display:block;font-weight:500;font-size:.7rem;letter-spacing:.01em;
  color:var(--muted);margin-top:1px;
}
.head-spacer{flex:1}

/* Header buttons */
.head-btn,.theme-toggle{
  display:inline-flex;align-items:center;justify-content:center;gap:7px;
  background:var(--surface-2);color:var(--ink-2);
  border:1px solid var(--line-strong);
  padding:8px 14px;border-radius:10px;cursor:pointer;
  font-size:.85rem;font-weight:600;font-family:inherit;
  transition:background-color .15s,border-color .15s,transform .14s var(--ease),box-shadow .15s;
}
.head-btn:hover,.theme-toggle:hover{
  background:var(--accent-soft);color:var(--accent-ink);
  border-color:var(--accent-line);transform:translateY(-1px);
}
.head-btn:active{transform:translateY(0)}
.head-btn:focus-visible,.theme-toggle:focus-visible{box-shadow:var(--ring)}
/* circular toggle with a tasteful rotate-on-hover delight (cand4, reduced-motion-gated) */
.theme-toggle{width:40px;height:38px;padding:0;font-size:1.05rem;line-height:1}
.theme-toggle:hover{transform:translateY(-1px) rotate(-12deg)}
.theme-toggle:active{transform:scale(.94)}

/* ---------- Layout ---------- */
main{max-width:1080px;margin:0 auto;padding:28px 20px 96px}

/* ---------- Home: hero ---------- */
.intro{
  position:relative;overflow:hidden;
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);
  padding:26px 26px 24px;box-shadow:var(--sh-2);margin-bottom:30px;
}
.intro::before{   /* soft blurred gradient blob (cand4-flavored) */
  content:"";position:absolute;inset:0 0 auto auto;width:300px;height:300px;
  pointer-events:none;border-radius:50%;
  background:radial-gradient(closest-side,
            color-mix(in srgb,var(--accent) 22%,transparent) 0%,transparent 72%);
  transform:translate(34%,-42%);filter:blur(6px);
}
.intro>*{position:relative}
.intro h1{
  margin:.05em 0 .35em;font-family:var(--serif);font-size:1.85rem;font-weight:700;
  letter-spacing:-.01em;line-height:1.18;color:var(--ink);
}
.intro p{margin:.4em 0;color:var(--ink-2);max-width:70ch}
.intro strong{color:var(--ink);font-weight:700}

.rules{display:flex;flex-wrap:wrap;gap:9px;margin-top:18px}
.rule{
  background:var(--accent-soft);color:var(--accent-ink);
  border:1px solid var(--accent-line);
  border-radius:999px;padding:7px 13px;font-size:.82rem;font-weight:600;
}
.rule.neg{background:var(--red-soft);color:var(--red);border-color:var(--red-line)}
.rule.con{background:var(--amber-soft);color:var(--amber);border-color:var(--amber-line)}

/* ---------- Sections ---------- */
.section{margin:34px 0 8px}
.section h2{
  font-family:var(--serif);font-size:1.32rem;font-weight:700;letter-spacing:-.01em;
  margin:0 0 5px;display:flex;align-items:center;gap:10px;color:var(--ink);
}
.section .pill{
  font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  font-size:.68rem;font-weight:800;letter-spacing:.04em;
  padding:4px 10px;border-radius:999px;
  background:linear-gradient(135deg,var(--accent),var(--accent2));color:#fff;
  box-shadow:0 2px 8px -2px var(--glow);
}
html[data-theme="dark"] .section .pill{color:#0c1024}  /* dark text-on-accent (cand2) */
.section .pill.c2{background:linear-gradient(135deg,var(--sky),#2563eb)}
.section .pill.study{background:linear-gradient(135deg,#16a34a,#0d9488)}
.section .desc{color:var(--muted);font-size:.88rem;margin:0 0 16px;max-width:70ch}

/* ---------- Cards grid ---------- */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(224px,1fr));gap:15px}
.card{
  position:relative;overflow:hidden;
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-md);
  padding:17px 17px 15px;box-shadow:var(--sh-1);cursor:pointer;
  display:flex;flex-direction:column;gap:6px;min-height:120px;
  transition:transform .16s var(--ease),box-shadow .16s ease,border-color .16s ease;
}
.card::before{   /* glowing accent rail (cand3), widens on hover (cand4) */
  content:"";position:absolute;left:0;top:0;bottom:0;width:4px;
  background:var(--accent);opacity:.9;box-shadow:0 0 12px -1px var(--glow);
  transition:width .16s var(--ease);
}
.card.exam::before{background:linear-gradient(var(--accent),var(--accent2))}
.card.study::before{background:linear-gradient(#16a34a,#0d9488);box-shadow:0 0 12px -1px rgba(13,148,136,.4)}
.card.rand::before{background:linear-gradient(#f59e0b,#ea580c);box-shadow:0 0 12px -1px rgba(234,88,12,.4)}
.card:hover{
  transform:translateY(-4px);
  box-shadow:var(--sh-3);border-color:var(--accent-line);
}
.card:hover::before{width:7px}
.card:active{transform:translateY(-1px) scale(.995)}   /* touch feedback */
.card:focus-visible{outline:none;box-shadow:var(--ring);border-color:var(--accent-line)}
.card .ct{font-weight:700;font-size:1rem;letter-spacing:-.01em;padding-left:6px}
.card .cs{color:var(--muted);font-size:.82rem;flex:1;padding-left:6px}
.card .cmeta{
  display:flex;align-items:center;justify-content:space-between;
  gap:8px;font-size:.76rem;padding-left:6px;margin-top:2px;
}
.card .badge{
  background:var(--accent-soft);color:var(--accent-ink);
  border:1px solid var(--accent-line);
  border-radius:7px;padding:3px 9px;font-weight:700;font-size:.72rem;
}
.card .best{
  color:var(--green);font-weight:700;font-size:.74rem;
  background:var(--green-soft);border:1px solid var(--green-line);
  padding:3px 8px;border-radius:7px;
}

/* ---------- Quiz header (sticky) ---------- */
.quiz-head{
  background:color-mix(in srgb,var(--surface) 88%,transparent);
  backdrop-filter:saturate(150%) blur(10px);
  -webkit-backdrop-filter:saturate(150%) blur(10px);
  border:1px solid var(--line);border-radius:var(--r-md);
  padding:16px 20px;box-shadow:var(--sh-2);margin-bottom:18px;
  position:sticky;top:calc(var(--header-h) + 8px);z-index:30;
}
.quiz-head h2{
  font-family:var(--serif);margin:0 0 3px;font-size:1.3rem;font-weight:700;letter-spacing:-.01em;
}
.quiz-head .sub{color:var(--muted);font-size:.85rem}
.progress-wrap{
  height:8px;background:var(--surface-2);border:1px solid var(--line);
  border-radius:999px;margin-top:13px;overflow:hidden;
}
.progress-bar{   /* glowing fill (cand3) */
  height:100%;width:0;border-radius:999px;
  background:linear-gradient(90deg,var(--accent),var(--accent2));
  box-shadow:0 0 12px -1px var(--glow);
  transition:width .35s var(--ease);
}

/* ---------- Question card ---------- */
.q{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-md);
  padding:20px 22px;box-shadow:var(--sh-1);margin-bottom:16px;
}
.q .qnum{
  font-size:.7rem;font-weight:800;color:var(--accent);
  letter-spacing:.06em;text-transform:uppercase;
}
.qhead{
  display:flex;justify-content:space-between;align-items:center;
  gap:6px 12px;flex-wrap:wrap;margin-bottom:4px;
}
.q .qtopic{
  font-size:.72rem;color:var(--muted);font-weight:600;
  background:var(--surface-2);border:1px solid var(--line);
  padding:2px 9px;border-radius:999px;
}
/* roomier long-reading question text (cand2) */
.q .qtext{font-weight:600;margin:9px 0 16px;font-size:1.06rem;line-height:1.6}

/* ---------- Options ---------- */
.opt{
  display:flex;align-items:flex-start;gap:12px;
  padding:12px 14px;border:1.5px solid var(--line);border-radius:var(--r-sm);
  margin:9px 0;cursor:pointer;background:var(--surface);
  transition:border-color .14s,background-color .14s,box-shadow .14s,transform .08s;
}
.opt:hover{border-color:var(--accent-line);background:var(--accent-soft)}
.opt:active{transform:scale(.997)}
/* keyboard focus on the checkbox lights the whole option row (cand4) */
.opt:focus-within{box-shadow:var(--ring);border-color:var(--accent)}
.opt input[type=checkbox]{
  appearance:none;-webkit-appearance:none;
  margin:1px 0 0;width:20px;height:20px;flex:none;cursor:pointer;
  border:2px solid var(--line-strong);border-radius:6px;
  background:var(--surface);position:relative;
  transition:border-color .14s,background-color .14s,box-shadow .14s;
}
.opt input[type=checkbox]:hover{border-color:var(--accent)}
.opt input[type=checkbox]:focus-visible{box-shadow:var(--ring)}
.opt input[type=checkbox]:checked{
  background:linear-gradient(135deg,var(--accent),var(--accent2));
  border-color:transparent;
}
.opt input[type=checkbox]:checked::after{   /* custom-drawn checkmark */
  content:"";position:absolute;left:5.5px;top:1.5px;width:5px;height:10px;
  border:solid #fff;border-width:0 2.5px 2.5px 0;transform:rotate(42deg);
}
.opt input[type=checkbox]:disabled{cursor:default;opacity:.85}
.opt .otext{flex:1;line-height:1.5}
.opt .mark{font-weight:800;margin-left:auto;flex:none;font-size:.8rem;white-space:nowrap}

/* selected (pre-submit) */
.opt.sel{
  border-color:var(--accent);background:var(--accent-soft);
  box-shadow:inset 0 0 0 1px var(--accent);
}

/* post-submit feedback — three DISTINCT border SHAPES (cand2): color-blind-safe.
   correct = solid · wrong = dashed · missed = dotted · + tint + 2px weight + glyph */
.opt.correct{border-color:var(--green);border-width:2px;border-style:solid;background:var(--green-soft)}
.opt.wrong{border-color:var(--red);border-width:2px;border-style:dashed;background:var(--red-soft)}
.opt.missed{border-color:var(--amber);border-width:2px;border-style:dotted;background:var(--amber-soft)}
.opt.correct .mark{color:var(--green)}
.opt.wrong .mark{color:var(--red)}
.opt.missed .mark{color:var(--amber)}
.opt.correct,.opt.wrong,.opt.missed{cursor:default}

/* ---------- Explanation + per-question score ---------- */
.explain{
  margin-top:14px;padding:13px 15px;border-radius:var(--r-sm);
  background:var(--accent-soft);border:1px solid var(--accent-line);
  border-left:4px solid var(--accent);
  font-size:.9rem;line-height:1.6;color:var(--ink-2);display:none;
}
.explain.show{display:block}
.explain strong{color:var(--ink)}
.qscore{font-size:.8rem;font-weight:800;margin-top:10px}

/* ---------- Submit bar (sticky bottom, frosted) ---------- */
.submitbar{
  position:sticky;bottom:0;z-index:40;
  background:var(--surface);   /* opaque fallback when backdrop-filter unsupported (cand3) */
  border-top:1px solid var(--line);
  padding:14px 20px;margin:0 -20px -80px;        /* preserve full-bleed bleed */
  display:flex;align-items:center;gap:14px;flex-wrap:wrap;
  box-shadow:0 -8px 24px -16px rgba(15,23,42,.3);
}
@supports ((backdrop-filter:blur(8px)) or (-webkit-backdrop-filter:blur(8px))){
  .submitbar{
    background:color-mix(in srgb,var(--surface) 82%,transparent);
    backdrop-filter:saturate(160%) blur(12px);
    -webkit-backdrop-filter:saturate(160%) blur(12px);
  }
}
.btn{
  border:none;border-radius:var(--r-sm);padding:11px 22px;
  font-size:.95rem;font-weight:700;font-family:inherit;cursor:pointer;
  transition:transform .12s var(--ease),box-shadow .15s,filter .15s,background-color .15s;
}
.btn:active{transform:translateY(1px)}
.btn:focus-visible{outline:none;box-shadow:var(--ring)}
.btn-primary{
  background:linear-gradient(135deg,var(--accent),var(--accent2));color:#fff;
  box-shadow:0 6px 16px -6px var(--glow);
}
html[data-theme="dark"] .btn-primary{color:#0c1024}  /* dark text-on-accent (cand2) */
.btn-primary:hover{transform:translateY(-1px);filter:brightness(1.06);
  box-shadow:0 10px 22px -8px var(--glow)}
.btn-primary:active{transform:translateY(0)}
.btn-ghost{
  background:var(--surface-2);color:var(--ink-2);border:1px solid var(--line-strong);
}
.btn-ghost:hover{background:var(--accent-soft);color:var(--accent-ink);
  border-color:var(--accent-line)}
.answered{color:var(--muted);font-size:.86rem;font-weight:600}

/* ---------- Results ---------- */
.result{
  position:relative;overflow:hidden;
  background:var(--surface);border:1px solid var(--line);border-radius:var(--r-lg);
  padding:28px 24px;box-shadow:var(--sh-2);margin-bottom:22px;text-align:center;
}
.result::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(440px 220px at 50% -12%,
            color-mix(in srgb,var(--accent) 14%,transparent) 0%,transparent 70%);
}
.result>*{position:relative}

/* Dual-layer glowing score-ring (cand3) on cand1's clean track.
   Outer conic accent track + masked inner accent2 arc + soft glow.
   --p is registered so the ring animates (counts up) on result reveal. */
@property --p{ syntax:"<number>"; inherits:true; initial-value:0; }
.score-ring{
  --p:0;width:142px;height:142px;border-radius:50%;margin:6px auto 14px;
  background:conic-gradient(var(--accent) calc(var(--p)*1%),var(--line) 0);
  display:grid;place-items:center;position:relative;
  box-shadow:0 0 0 1px var(--line) inset,0 0 34px var(--glow);
  transition:--p 1.1s cubic-bezier(.2,.7,.3,1);
}
.score-ring::after{
  content:"";position:absolute;inset:7px;border-radius:50%;pointer-events:none;
  background:conic-gradient(var(--accent2) calc(var(--p)*1%),transparent 0);
  -webkit-mask:radial-gradient(farthest-side,transparent calc(100% - 3px),#000 0);
  mask:radial-gradient(farthest-side,transparent calc(100% - 3px),#000 0);
  opacity:.55;
}
.score-ring .inner{
  width:108px;height:108px;border-radius:50%;background:var(--surface);
  display:grid;place-items:center;position:relative;z-index:1;
  box-shadow:inset 0 0 0 1px var(--line);
}
.score-ring .pct{   /* gradient-clipped percentage (cand4) with solid color fallback */
  font-size:1.7rem;font-weight:800;letter-spacing:-.02em;color:var(--accent-ink);
  background:linear-gradient(135deg,var(--accent),var(--accent2));
  -webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;
}
.score-big{font-family:var(--serif);font-size:3rem;font-weight:700;line-height:1;margin:6px 0;letter-spacing:-.01em;color:var(--ink)}
.score-sub{color:var(--muted);font-weight:600}
.grade{
  display:inline-block;margin-top:12px;padding:7px 18px;border-radius:999px;
  font-weight:800;letter-spacing:.02em;border:1.5px solid transparent;
}
.grade.pass{background:var(--green-soft);color:var(--green);border-color:var(--green-line)}
.grade.fail{background:var(--red-soft);color:var(--red);border-color:var(--red-line)}  /* fail stays RED (avoided cand4's amber) */

/* ---------- Footer ---------- */
.footer{
  color:var(--muted);font-size:.8rem;text-align:center;margin-top:36px;line-height:1.6;
  padding-top:18px;border-top:1px solid var(--line);
}

/* ---------- Responsive (phones) ---------- */
@media(max-width:600px){
  :root{--header-h:54px}
  main{padding:16px 14px calc(92px + env(safe-area-inset-bottom))}

  /* Header: compact single line, bigger tap targets, safe-area sides */
  header{padding-left:env(safe-area-inset-left);padding-right:env(safe-area-inset-right)}
  .head-inner{padding:0 12px;gap:8px}
  .brand{font-size:1.02rem;gap:9px}
  .brand small{display:none}            /* hide subtitle → no 2-line wrap */
  .brand .logo{width:32px;height:32px}
  .head-btn{padding:0 15px;min-height:42px}
  .theme-toggle{width:42px;height:42px;font-size:1.12rem}

  /* Hero */
  .intro{padding:20px 16px}
  .intro h1{font-size:1.46rem}
  .intro p{font-size:.95rem}
  .intro::before{width:200px;height:200px}
  .rules{gap:8px;margin-top:14px}
  .rule{border-radius:12px;font-size:.8rem;padding:7px 12px}

  /* Sections + cards */
  .section{margin:28px 0 8px}
  .section h2{font-size:1.2rem}
  .grid{grid-template-columns:1fr 1fr;gap:11px}
  .card{min-height:0;padding:14px 13px 12px}
  .card .ct{font-size:.92rem;line-height:1.25}
  .card .cs{font-size:.78rem}
  .card .cmeta{flex-wrap:wrap;gap:6px}

  /* Quiz header: NOT sticky on mobile → reclaims space, removes overlap glitch */
  .quiz-head{position:static;padding:15px 16px;margin-bottom:14px}
  .quiz-head h2{font-size:1.16rem}

  /* Question + options (touch-friendly) */
  .q{padding:16px 15px}
  .qhead{margin-bottom:6px}
  .q .qtext{font-size:1.05rem;margin:8px 0 14px}
  .opt{padding:13px 13px;gap:12px;margin:8px 0}
  .opt input[type=checkbox]{width:22px;height:22px}
  .opt input[type=checkbox]:checked::after{left:6.5px;top:2.5px}
  .opt .otext{font-size:.98rem}
  .explain{font-size:.9rem;padding:12px 14px}

  /* Submit bar: full-bleed + safe-area (home indicator) aware */
  .submitbar{
    padding:12px 14px;
    padding-bottom:calc(12px + env(safe-area-inset-bottom));
    margin:0 -14px calc(-92px - env(safe-area-inset-bottom));
    gap:10px 12px;
  }
  .btn{padding:11px 18px;font-size:.92rem;flex:1 1 auto;min-width:128px}
  .answered{flex-basis:100%;order:3;margin-top:-2px}

  /* Result */
  .result{padding:24px 18px}
  .score-big{font-size:2.5rem}
  .score-ring{width:128px;height:128px}
  .score-ring .inner{width:96px;height:96px}
  .score-ring .pct{font-size:1.55rem}
}

/* Very narrow phones: single-column menu so long titles stay readable */
@media(max-width:340px){
  .grid{grid-template-columns:1fr}
  .intro h1{font-size:1.32rem}
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    transition:none!important;animation:none!important;scroll-behavior:auto!important;
  }
  .card:hover{transform:none}
  .theme-toggle:hover{transform:none}   /* disable rotate delight */
  body{background-attachment:scroll}
}