:root{
    --navy:#0A1428;
    --navy-2:#101E3A;
    --paper:#FAF7F0;
    --paper-2:#F1EADC;
    --ink:#14181F;
    --ink-soft:#57616F;
    --maple:#FF3B4E;
    --maple-2:#D81E36;
    --gold:#FFC94A;
    --aurora:#5EEAD4;
    --line:#E6DFCF;
    --line-dark:#28365A;
    --card:#FFFFFF;
    --radius:16px;
    --mono:'JetBrains Mono',ui-monospace,monospace;
    --serif:'Noto Serif SC','Songti SC',serif;
    --sans:'Noto Sans SC','Helvetica Neue',Arial,sans-serif;
  }
  *{box-sizing:border-box;}
  html{scroll-behavior:smooth;}
  body{
    margin:0;background:var(--paper);color:var(--ink);
    font-family:var(--sans);line-height:1.7;
    -webkit-font-smoothing:antialiased;
  }
  h1,h2,h3{font-family:var(--serif);color:var(--navy);line-height:1.3;margin:0 0 .5em;}
  a{color:inherit;text-decoration:none;}
  .wrap{max-width:1120px;margin:0 auto;padding:0 24px;}
  :focus-visible{outline:3px solid var(--gold);outline-offset:3px;}
 
  /* ---------- Header ---------- */
  header.site{
    position:sticky;top:0;z-index:30;
    background:rgba(250,247,240,.85);backdrop-filter:blur(10px);
    border-bottom:1px solid var(--line);
  }
  .nav{display:flex;align-items:center;justify-content:space-between;padding:16px 0;}
  .brand{font-family:var(--serif);font-weight:900;font-size:1.2rem;color:var(--navy);display:flex;align-items:center;gap:8px;}
  .brand .leaf{color:var(--maple);font-size:1.3rem;}
  .nav-main{display:flex;align-items:center;gap:30px;flex-wrap:wrap;}
  .nav ul{list-style:none;display:flex;gap:30px;margin:0;padding:0;font-size:.94rem;color:var(--ink-soft);}
  .nav ul a{position:relative;padding:4px 0;}
  .nav ul a::after{
    content:"";position:absolute;left:0;bottom:-2px;width:0;height:2px;background:var(--maple);
    transition:width .25s ease;
  }
  .nav ul a:hover::after{width:100%;}
  .nav ul a:hover{color:var(--navy);}
 
  /* ---------- Hero (Aurora) ---------- */
  .hero{
    position:relative;overflow:hidden;
    background:radial-gradient(ellipse at 20% -10%, #16264A 0%, var(--navy) 55%), var(--navy);
    color:#fff;padding:100px 0 80px;
  }
  .aurora{
    position:absolute;inset:0;pointer-events:none;
    background:
      radial-gradient(60% 50% at 80% 0%, rgba(94,234,212,.22), transparent 60%),
      radial-gradient(50% 45% at 30% 10%, rgba(255,59,78,.16), transparent 60%),
      radial-gradient(45% 40% at 60% 40%, rgba(255,201,74,.10), transparent 65%);
    animation:driftAurora 16s ease-in-out infinite alternate;
  }
  @keyframes driftAurora{
    0%{transform:translate3d(0,0,0) scale(1);}
    100%{transform:translate3d(-2%,3%,0) scale(1.06);}
  }


/* Hero title full width layout */
.hero-container{
  position:relative;
  z-index:2;
}

.hero-title{
  text-align:center;
  max-width:1120px;
  margin:0 auto 50px;
}

.hero-title .eyebrow{
  justify-content:center;
}

.hero-title h1{
  align-items:center;
  max-width:none;
  margin-left:auto;
  margin-right:auto;
  font-size:clamp(2.4rem,5vw,3.8rem);
}

@media(max-width:900px){
  .hero-title{
    margin-bottom:30px;
  }

  .hero-title h1{
    font-size:2rem;
  }
}
  .hero-grid{
    position:relative;z-index:2;
    display:grid;grid-template-columns:1.15fr .85fr;gap:56px;align-items:center;
  }
  .eyebrow{
    display:inline-flex;align-items:center;gap:8px;
    font-family:var(--mono);font-size:.76rem;letter-spacing:.1em;
    color:var(--gold);font-weight:700;margin-bottom:16px;text-transform:uppercase;
  }
  .eyebrow::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--gold);
    box-shadow:0 0 0 4px rgba(255,201,74,.25);}
  .hero h1{
    font-size:clamp(2.2rem,4.6vw,3.4rem);color:#fff;max-width:43ch;font-weight:900;align-items:center;
  }
  .hero h1 em{font-style:normal;color:var(--aurora);}
  .hero p.sub{font-size:1.12rem;color:#C9D2E3;max-width:52ch;margin-bottom:30px;}
  .cta-row{display:flex;gap:14px;flex-wrap:wrap;margin-bottom:34px;}
  .btn{
    display:inline-flex;align-items:center;gap:8px;
    padding:15px 28px;border-radius:999px;font-weight:700;font-size:1rem;
    transition:transform .2s ease, box-shadow .2s ease, background .2s ease;
    border:none;cursor:pointer;
  }
  .btn-primary{background:linear-gradient(135deg,var(--maple),var(--maple-2));color:#fff;
    box-shadow:0 10px 30px -8px rgba(255,59,78,.55);}
  .btn-primary:hover{transform:translateY(-2px);box-shadow:0 14px 34px -6px rgba(255,59,78,.65);}
  .btn-secondary{background:rgba(255,255,255,.06);color:#fff;border:1.5px solid rgba(255,255,255,.35);}
  .btn-secondary:hover{background:rgba(255,255,255,.14);}
 
  .trust{display:flex;flex-wrap:wrap;gap:10px 22px;color:#AEB9CC;font-size:.9rem;font-family:var(--mono);}
  .trust span::before{content:"✓";color:var(--aurora);font-weight:700;margin-right:6px;}
 
  /* Flip card demo */
  .flipcard{
    perspective:1200px;height:280px;cursor:pointer;
  }
  .flipcard-inner{
    position:relative;width:100%;height:100%;
    transition:transform .7s cubic-bezier(.2,.7,.2,1);
    transform-style:preserve-3d;
  }
  .flipcard.flipped .flipcard-inner{transform:rotateY(180deg);}
  .flip-face{
    position:absolute;inset:0;backface-visibility:hidden;
    border-radius:20px;padding:26px;display:flex;flex-direction:column;justify-content:space-between;
    box-shadow:0 24px 50px -18px rgba(0,0,0,.5);
  }
  .flip-front{background:linear-gradient(160deg,#16233D,#0E1830);border:1px solid var(--line-dark);color:#fff;}
  .flip-back{background:linear-gradient(160deg,var(--maple-2),#7A0F22);color:#fff;transform:rotateY(180deg);}
  .flip-tag{font-family:var(--mono);font-size:.72rem;letter-spacing:.08em;color:var(--gold);text-transform:uppercase;}
  .flip-q{font-size:1.15rem;font-weight:700;margin-top:14px;}
  .flip-hint{font-size:.85rem;color:#9FB0CC;font-family:var(--mono);}
  .flip-a{font-size:1.05rem;font-weight:700;margin-top:14px;}
  .flip-exp{font-size:.9rem;color:#FBD9DD;margin-top:6px;}
 
  .stat-bar{
    position:relative;z-index:2;
    margin-top:64px;display:grid;grid-template-columns:repeat(4,1fr);
    border-top:1px solid rgba(255,255,255,.14);padding-top:28px;
  }
  .stat b{
    display:block;font-family:var(--mono);font-size:2rem;color:#fff;font-weight:700;
  }
  .stat span{color:#9FB0CC;font-size:.86rem;}
 
  /* ---------- Page hero (inner listing pages, e.g. 题库) ---------- */
  .pagehero{
    position:relative;overflow:hidden;
    background:radial-gradient(ellipse at 20% -10%, #16264A 0%, var(--navy) 55%), var(--navy);
    color:#fff;padding:90px 0 70px;
  }
  .pagehero .wrap{position:relative;z-index:2;}
  .pagehero .aurora{position:absolute;inset:0;pointer-events:none;}
  .crumb{font-family:var(--mono);font-size:.82rem;color:#9FB0CC;margin-bottom:18px;}
  .crumb a{color:#C9D2E3;text-decoration:underline;}
  .pagehero h1{font-size:clamp(2rem,4.2vw,3rem);color:#fff;font-weight:900;max-width:40ch;margin-bottom:14px;}
  .pagehero > .wrap > p{font-size:1.05rem;color:#C9D2E3;max-width:62ch;margin:0;}

  .hero-stats{
    position:relative;z-index:2;
    display:grid;grid-template-columns:repeat(3,1fr);gap:20px;
    margin-top:44px;border-top:1px solid rgba(255,255,255,.14);padding-top:28px;
  }
  .hero-stats b{display:block;font-family:var(--mono);font-size:2rem;color:#fff;font-weight:700;}
  .hero-stats span{color:#9FB0CC;font-size:.86rem;}

  /* Category card layout (num / title / count / desc / go) */
  .cat-card{display:flex;gap:16px;align-items:flex-start;}
  .cat-num{font-family:var(--mono);font-weight:700;font-size:1.1rem;color:var(--aurora);flex:0 0 auto;}
  .cat-card h3{font-size:1.05rem;margin-bottom:6px;}
  .cat-card .count{
    display:inline-block;font-family:var(--mono);font-size:.76rem;color:var(--maple-2);
    background:var(--paper-2);padding:2px 8px;border-radius:999px;margin-bottom:8px;
  }
  .cat-card p{font-size:.88rem;color:var(--ink-soft);margin:0 0 10px;}
  .cat-card .go{font-size:.86rem;font-weight:700;color:var(--maple);transition:transform .2s ease;}
  .cat-card:hover .go{transform:translateX(3px);}

  /* Sample question demo (copy + flipcard side by side) */
  .sample-wrap{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center;margin-top:36px;}
  .sample-copy{padding-right:10px;}

  /* ---------- Generic sections ---------- */
  section{padding:80px 0;}
  section.alt{background:var(--paper-2);}
  .eyebrow-dark{
    display:inline-flex;align-items:center;gap:8px;
    font-family:var(--mono);font-size:.76rem;letter-spacing:.1em;color:var(--maple-2);
    font-weight:700;margin-bottom:12px;text-transform:uppercase;
  }
  .eyebrow-dark::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--maple);}
 
  .reveal{opacity:0;transform:translateY(24px);transition:opacity .7s ease, transform .7s ease;}
  .reveal.in-view{opacity:1;transform:translateY(0);}
 
  /* Steps */
  .steps{position:relative;display:grid;grid-template-columns:repeat(3,1fr);gap:24px;margin-top:36px;}
  .steps::before{
    content:"";position:absolute;top:38px;left:8%;right:8%;height:2px;
    background:repeating-linear-gradient(90deg,var(--maple) 0 10px, transparent 10px 18px);
    opacity:.5;
  }
  .step-card{position:relative;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:30px;
    transition:transform .25s ease, box-shadow .25s ease;}
  .step-card:hover{transform:translateY(-6px);box-shadow:0 20px 40px -20px rgba(20,24,31,.25);}
  .step-num{font-family:var(--mono);color:#fff;background:var(--maple);width:44px;height:44px;border-radius:50%;
    display:flex;align-items:center;justify-content:center;font-weight:700;margin-bottom:16px;}
 
  /* Features */
  .feature-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:22px;margin-top:36px;}
  .feature-card{
    background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:28px;
    position:relative;overflow:hidden;transition:transform .25s ease, box-shadow .25s ease;
  }
  .feature-card::before{
    content:"";position:absolute;top:0;left:0;width:4px;height:100%;background:var(--gold);
    transform:scaleY(0);transform-origin:top;transition:transform .3s ease;
  }
  .feature-card:hover{transform:translateY(-5px);box-shadow:0 20px 44px -22px rgba(20,24,31,.28);}
  .feature-card:hover::before{transform:scaleY(1);}
 
  /* Categories */
  .cat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:36px;}
  .cat-card{
    background:var(--card);border:1px solid var(--line);border-radius:12px;padding:20px;font-size:.94rem;
    border-left:4px solid var(--aurora);transition:border-color .25s ease, transform .25s ease;
  }
  .cat-card:hover{border-left-color:var(--maple);transform:translateX(4px);}
  .cat-card b{display:block;color:var(--navy);margin-bottom:4px;font-family:var(--serif);}
 
  /* Practice tests */
  .test-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-top:36px;}
  .test-card{
    position:relative;background:linear-gradient(160deg,#16233D,#0E1830);color:#fff;border-radius:var(--radius);
    padding:30px;overflow:hidden;transition:transform .25s ease;
  }
  .test-card:hover{transform:translateY(-6px);}
  .test-card h3{color:#fff;}
  .test-card ul{padding-left:0;list-style:none;color:#B9C4D8;font-size:.9rem;margin:14px 0 0;}
  .test-card li{padding:4px 0;}
  .test-card li::before{content:"→ ";color:var(--gold);}
  .ring{
    position:absolute;top:20px;right:20px;width:56px;height:56px;
  }
  .ring circle{fill:none;stroke-width:5;}
  .ring .bg{stroke:rgba(255,255,255,.15);}
  .ring .fg{stroke:var(--aurora);stroke-linecap:round;stroke-dasharray:151;stroke-dashoffset:151;
    transition:stroke-dashoffset 1.4s ease;}
  .ring.in-view .fg{stroke-dashoffset:22;}
 
  /* Why us */
  .why-list{list-style:none;padding:0;margin-top:28px;display:grid;gap:14px;}
  .why-list li{
    background:var(--card);border:1px solid var(--line);border-radius:12px;
    padding:18px 22px;display:flex;gap:14px;align-items:flex-start;
  }
  .why-list .check{
    flex:0 0 auto;width:26px;height:26px;border-radius:50%;background:var(--maple);color:#fff;
    display:flex;align-items:center;justify-content:center;font-size:.8rem;font-weight:700;
  }
  .why-list b{color:var(--maple-2);}
 
  /* Blog */
  .article-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px;margin-top:36px;}
  .article-card{
    background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px;
    transition:transform .25s ease, box-shadow .25s ease;
  }
  .article-card:hover{transform:translateY(-4px) scale(1.01);box-shadow:0 20px 40px -22px rgba(20,24,31,.25);}
 
  /* FAQ */
  .faq-item{border-bottom:1px solid var(--line);padding:6px 0;}
  .faq-item summary{
    list-style:none;cursor:pointer;font-weight:700;color:var(--navy);
    display:flex;align-items:center;justify-content:space-between;padding:16px 0;
  }
  .faq-item summary::-webkit-details-marker{display:none;}
  .faq-item summary .chev{transition:transform .25s ease;color:var(--maple);font-family:var(--mono);}
  .faq-item[open] summary .chev{transform:rotate(45deg);}
  .faq-item p{color:var(--ink-soft);margin:0 0 18px;}
 
  /* Closing */
  .closing{
    position:relative;overflow:hidden;background:var(--navy);color:#fff;text-align:center;
    padding:76px 24px;border-radius:24px;margin:0 24px;
  }
  .closing .aurora{animation-duration:12s;}
  .closing h2{color:#fff;position:relative;z-index:2;}
  .closing p{position:relative;z-index:2;color:#C9D2E3;max-width:56ch;margin:0 auto 26px;}
  .closing .btn-primary{position:relative;z-index:2;}
 
  /* ---------- Footer (全站通用) ---------- */
  footer.site{
    position:relative;overflow:hidden;
    background:radial-gradient(ellipse at 80% 0%, #16264A 0%, var(--navy) 60%), var(--navy);
    color:#C9D2E3;padding:64px 0 0;margin-top:80px;font-size:.9rem;
  }
  footer.site .aurora{animation-duration:22s;opacity:.6;}

  .ftr-top{
    position:relative;z-index:2;
    display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:40px;
    padding-bottom:44px;border-bottom:1px solid rgba(255,255,255,.12);
  }

  .ftr-brand .brand{color:#fff;margin-bottom:14px;}
  .ftr-tag{font-size:.92rem;color:#AEB9CC;line-height:1.7;margin:0 0 14px;max-width:36ch;}
  .ftr-tag em{color:var(--aurora);font-style:normal;}
  .ftr-disclaimer{
    font-size:.8rem;color:#8592AA;line-height:1.6;margin:0 0 20px;
    padding:10px 14px;border-left:2px solid var(--gold);background:rgba(255,201,74,.06);
    border-radius:4px;max-width:38ch;
  }
  .ftr-lang{display:flex;gap:14px;font-family:var(--mono);font-size:.82rem;}
  .ftr-lang a{color:#9FB0CC;padding:4px 0;border-bottom:1px solid transparent;}
  .ftr-lang a:hover,.ftr-lang a.current{color:var(--aurora);border-color:var(--aurora);}

  .ftr-col h4{
    font-family:var(--serif);color:#fff;font-size:.94rem;font-weight:700;
    margin:0 0 16px;letter-spacing:.02em;
  }
  .ftr-col ul{list-style:none;margin:0;padding:0;display:grid;gap:10px;}
  .ftr-col a{
    font-size:.9rem;color:#AEB9CC;display:inline-block;
    transition:color .2s ease, padding-left .2s ease;
  }
  .ftr-col a:hover{color:var(--aurora);padding-left:3px;}

  .ftr-bottom{
    position:relative;z-index:2;
    display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:10px;
    padding:22px 0;font-size:.82rem;color:#8592AA;
  }
  .ftr-bottom a{color:#9FB0CC;text-decoration:underline;text-underline-offset:2px;}
  .ftr-bottom a:hover{color:var(--aurora);}
  .ftr-note{margin:0;}

  @media(max-width:900px){
    .ftr-top{grid-template-columns:1fr 1fr;}
    .ftr-brand{grid-column:1 / -1;}
  }
  @media(max-width:560px){
    .ftr-top{grid-template-columns:1fr;}
    .ftr-bottom{flex-direction:column;align-items:flex-start;}
  }
 
  @media(max-width:900px){
    .hero-grid{grid-template-columns:1fr;}
    .steps,.feature-grid,.cat-grid,.test-grid,.article-grid{grid-template-columns:1fr;}
    .stat-bar,.hero-stats{grid-template-columns:repeat(2,1fr);row-gap:20px;}
    .sample-wrap{grid-template-columns:1fr;}
    .cat-card{flex-direction:column;}
    .nav ul{display:none;}
    .steps::before{display:none;}
  }
  @media (prefers-reduced-motion: reduce){
    *{animation-duration:.001ms !important;animation-iteration-count:1 !important;transition-duration:.001ms !important;}
  }
  /* ---------- Quiz Card (题目卡片) ---------- */
  :root{
    --quiz-red:#d52b1e;
    --quiz-red-dark:#a81f16;
    --quiz-green:#1f7a3d;
    --quiz-green-bg:#eaf6ee;
    --quiz-border:#e6e2d8;
    --quiz-card-bg:#ffffff;
    --quiz-muted:#6b6459;
  }
  .quiz-wrap{ max-width:760px; margin:0 auto; }
  .quiz-card{
    background:var(--quiz-card-bg);
    border:1px solid var(--quiz-border);
    border-radius:16px;
    padding:32px 34px;
    box-shadow:0 2px 10px rgba(0,0,0,.04);
    margin-top:36px;
  }
  .quiz-head{ display:flex; align-items:center; gap:12px; margin-bottom:18px; }
  .quiz-num{
    font-family:'JetBrains Mono',monospace;
    font-weight:700;
    font-size:13px;
    color:#fff;
    background:var(--quiz-red);
    padding:4px 10px;
    border-radius:999px;
    letter-spacing:.03em;
  }
  .quiz-cat{ font-size:13px; color:var(--quiz-muted); }
  .quiz-question{ margin-bottom:22px; }
  .q-en{
    font-family:var(--serif);
    font-weight:900;
    font-size:1.35rem;
    line-height:1.55;
    margin:0 0 8px;
    color:#1c1a17;
  }
  .q-cn{ font-size:1.05rem; color:var(--quiz-muted); margin:0; }
  .quiz-options{ display:grid; gap:12px; }
  .opt{
    display:flex;
    align-items:flex-start;
    gap:14px;
    width:100%;
    text-align:left;
    background:#faf9f6;
    border:1px solid var(--quiz-border);
    border-radius:10px;
    padding:14px 16px;
    cursor:pointer;
    font:inherit;
    transition:border-color .15s ease, background .15s ease;
  }
  .opt:hover{ border-color:var(--quiz-red); }
  .opt-letter{
    flex:0 0 auto;
    width:28px;
    height:28px;
    border-radius:50%;
    background:#fff;
    border:1px solid var(--quiz-border);
    display:flex;
    align-items:center;
    justify-content:center;
    font-weight:700;
    font-size:.9rem;
  }
  .opt-text b{ font-weight:600; }
  .opt-cn{ display:block; font-size:.88rem; color:var(--quiz-muted); margin-top:3px; }
  .quiz-card.answered .opt{ cursor:default; }
  .quiz-card.answered .opt:hover{ border-color:var(--quiz-border); }
  .opt.is-correct{ background:var(--quiz-green-bg); border-color:var(--quiz-green); }
  .opt.is-correct .opt-letter{ background:var(--quiz-green); border-color:var(--quiz-green); color:#fff; }
  .opt.is-wrong{ background:#fdecea; border-color:var(--quiz-red); }
  .opt.is-wrong .opt-letter{ background:var(--quiz-red); border-color:var(--quiz-red); color:#fff; }
  .quiz-reveal{ margin-top:22px; padding-top:22px; border-top:1px dashed var(--quiz-border); }
  .reveal-answer{ display:inline-flex; align-items:center; gap:8px; font-weight:700; color:var(--quiz-green); margin-bottom:12px; }
  .exp-en{ margin:0 0 6px; font-size:1rem; color:#1c1a17; }
  .exp-cn{ margin:0; font-size:.95rem; color:var(--quiz-muted); }
  .quiz-hint{ font-size:.85rem; color:var(--quiz-muted); margin-top:16px; }
  .quiz-nav{
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:12px;
    margin-top:24px;
  }
  .quiz-nav a{
    flex:1;
    text-align:center;
    padding:12px 16px;
    border-radius:10px;
    border:1px solid var(--quiz-border);
    text-decoration:none;
    color:#1c1a17;
    font-weight:600;
    font-size:.92rem;
    transition:border-color .15s ease, color .15s ease;
  }
  .quiz-nav a:hover{ border-color:var(--quiz-red); color:var(--quiz-red); }
  .quiz-nav a.disabled{ pointer-events:none; opacity:.35; }
  .quiz-nav a.nav-list{ flex:0 0 auto; background:var(--quiz-red); color:#fff; border-color:var(--quiz-red); }
  .quiz-nav a.nav-list:hover{ color:#fff; }
  /* ---------- Quiz List Page (题库列表页 / 进度条 / 题目网格) ---------- */
  .quiz-wrap{ max-width:1080px; margin:0 auto; }
  /* 顶部进度条 */
  .quiz-progress{
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:16px;
    background:var(--quiz-card-bg);
    border:1px solid var(--quiz-border);
    border-radius:14px;
    padding:16px 20px;
    margin-top:36px;
    box-shadow:0 2px 10px rgba(0,0,0,.04);
  }
  .quiz-progress-label{ font-size:.92rem; color:var(--quiz-muted); }
  .quiz-progress-label b{ color:#1c1a17; font-family:'JetBrains Mono',monospace; }
  .quiz-progress-track{
    flex:1;
    height:8px;
    border-radius:999px;
    background:#f1efe8;
    overflow:hidden;
  }
  .quiz-progress-fill{
    height:100%;
    width:0%;
    background:var(--quiz-red);
    border-radius:999px;
  }
  /* 题目列表：响应式网格，桌面4列 / 平板3列 / 手机1列 */
  .quiz-list{
    display:grid;
    grid-template-columns:repeat(4, 1fr);
    gap:14px;
    margin-top:20px;
  }
  @media (max-width:920px){
    .quiz-list{ grid-template-columns:repeat(3, 1fr); }
  }
  @media (max-width:640px){
    .quiz-list{ grid-template-columns:repeat(2, 1fr); }
  }
  @media (max-width:420px){
    .quiz-list{ grid-template-columns:1fr; }
  }
  .quiz-item{
    display:flex;
    flex-direction:column;
    gap:10px;
    background:var(--quiz-card-bg);
    border:1px solid var(--quiz-border);
    border-radius:14px;
    padding:16px 16px 14px;
    text-decoration:none;
    color:inherit;
    box-shadow:0 2px 10px rgba(0,0,0,.03);
    transition:border-color .15s ease, transform .15s ease, box-shadow .15s ease;
    min-height:150px;
  }
  .quiz-item:hover{
    border-color:var(--quiz-red);
    transform:translateY(-2px);
    box-shadow:0 6px 16px rgba(213,43,30,.08);
  }
  .quiz-item-top{
    display:flex;
    align-items:center;
    justify-content:space-between;
  }
  .quiz-item-num{
    flex:0 0 auto;
    width:34px;
    height:34px;
    border-radius:50%;
    background:#faf9f6;
    border:1px solid var(--quiz-border);
    display:flex;
    align-items:center;
    justify-content:center;
    font-family:'JetBrains Mono',monospace;
    font-weight:700;
    font-size:.82rem;
    color:var(--quiz-red);
  }
  .quiz-item-arrow{
    flex:0 0 auto;
    font-size:1.05rem;
    color:var(--quiz-border);
    transition:color .15s ease, transform .15s ease;
  }
  .quiz-item:hover .quiz-item-arrow{ color:var(--quiz-red); transform:translateX(3px); }
  .quiz-item-body{ flex:1; min-width:0; }
  .quiz-item-en{
    font-family:'Noto Serif SC',serif;
    font-weight:700;
    font-size:.94rem;
    line-height:1.5;
    margin:0 0 6px;
    color:#1c1a17;
    display:-webkit-box;
    -webkit-line-clamp:3;
    -webkit-box-orient:vertical;
    overflow:hidden;
  }
  .quiz-item-cn{
    font-size:.82rem;
    color:var(--quiz-muted);
    margin:0;
    display:-webkit-box;
    -webkit-line-clamp:2;
    -webkit-box-orient:vertical;
    overflow:hidden;
  }
  /* 章节导航（返回题库 / 下一章） */
  .quiz-nav{
    display:flex;
    align-items:center;
    justify-content:space-between;
    gap:12px;
    margin-top:28px;
    margin-bottom:40px;
  }
  .quiz-nav a{
    flex:1;
    text-align:center;
    padding:12px 16px;
    border-radius:10px;
    border:1px solid var(--quiz-border);
    text-decoration:none;
    color:#1c1a17;
    font-weight:600;
    font-size:.92rem;
    transition:border-color .15s ease, color .15s ease;
  }
  .quiz-nav a:hover{ border-color:var(--quiz-red); color:var(--quiz-red); }
  .quiz-nav a.nav-primary{ flex:0 0 auto; background:var(--quiz-red); color:#fff; border-color:var(--quiz-red); }
  .quiz-nav a.nav-primary:hover{ color:#fff; }