/* ================= 基础 ================= */
:root{
  --primary:#4f6ef7;
  --primary-d:#3d5be0;
  --primary-l:#eef1ff;
  --violet:#8b5cf6;
  --success:#10b981;
  --success-l:#e7f9f2;
  --danger:#ef4444;
  --danger-l:#fdeced;
  --warn:#f59e0b;
  --ink:#1b2233;
  --ink-2:#3c4661;
  --muted:#667085;
  --line:#e8ebf3;
  --bg:#f4f6fb;
  --card:#ffffff;
  --radius:18px;
  --shadow:0 6px 24px rgba(24,35,84,.07);
  --shadow-h:0 12px 32px rgba(24,35,84,.12);
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;padding:0}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei","Hiragino Sans GB",sans-serif;
  background:var(--bg);
  color:var(--ink);
  font-size:15px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4,p{margin:0}
button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}
a{color:inherit;text-decoration:none}
.hidden{display:none !important}
.muted{color:var(--muted);font-weight:400;font-size:.86em}
.dark-muted{color:rgba(255,255,255,.75)}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px}

/* ================= 顶栏 ================= */
.topbar{
  position:sticky;top:0;z-index:40;
  background:rgba(255,255,255,.82);
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid rgba(232,235,243,.9);
}
.topbar-inner{display:flex;align-items:center;justify-content:space-between;height:66px;gap:16px}
.brand{display:flex;align-items:center;gap:12px;cursor:pointer;user-select:none;min-width:0}
.brand-logo{
  width:40px;height:40px;flex:0 0 40px;border-radius:12px;
  background:linear-gradient(135deg,#6366f1,#8b5cf6);
  color:#fff;font-weight:700;font-size:19px;display:grid;place-items:center;
  box-shadow:0 6px 14px rgba(99,102,241,.32);
}
.brand-text{display:flex;flex-direction:column;line-height:1.25;min-width:0}
.brand-text b{font-size:16px;letter-spacing:.3px;white-space:nowrap}
.brand-text small{font-size:11.5px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.nav{display:flex;gap:6px;background:#eff2f9;padding:4px;border-radius:14px;flex:0 0 auto}
.nav-btn{
  position:relative;padding:8px 16px;border-radius:11px;font-size:14px;font-weight:500;color:var(--ink-2);
  transition:.18s;white-space:nowrap;
}
.nav-btn:hover{color:var(--primary)}
.nav-btn.active{background:#fff;color:var(--primary);box-shadow:0 2px 8px rgba(24,35,84,.1);font-weight:600}
.dot-num{
  display:inline-grid;place-items:center;min-width:18px;height:18px;padding:0 5px;margin-left:5px;
  border-radius:9px;background:var(--danger);color:#fff;font-size:11px;font-style:normal;
  vertical-align:1px;font-weight:600;
}
.dot-num.zero{background:#c9cfdd}

/* ================= 屏幕 ================= */
.screen{display:none;padding:26px 0 70px;animation:fade .28s ease}
.screen.active{display:block}
@keyframes fade{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:none}}

.section-head{display:flex;align-items:center;justify-content:space-between;margin:30px 0 14px;gap:12px;flex-wrap:wrap}
.section-head h2{font-size:17px;font-weight:650;letter-spacing:.2px}
.page-head{display:flex;align-items:flex-end;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:6px}
.page-head h1{font-size:24px;font-weight:700;letter-spacing:.4px}
.page-head-actions{display:flex;gap:8px;flex-wrap:wrap}

/* ================= 首页 hero ================= */
.hero{
  position:relative;overflow:hidden;
  background:linear-gradient(125deg,#5b6cf8 0%,#7c5cf7 48%,#9a5cf0 100%);
  border-radius:24px;padding:30px 32px;color:#fff;
  display:flex;align-items:center;justify-content:space-between;gap:26px;
  box-shadow:0 16px 40px rgba(88,92,230,.28);
}
.hero::after{
  content:"";position:absolute;width:340px;height:340px;right:-90px;top:-140px;border-radius:50%;
  background:radial-gradient(circle,rgba(255,255,255,.22),transparent 68%);pointer-events:none;
}
.hero::before{
  content:"";position:absolute;width:220px;height:220px;left:38%;bottom:-150px;border-radius:50%;
  background:radial-gradient(circle,rgba(255,255,255,.14),transparent 70%);pointer-events:none;
}
.hero-main{position:relative;z-index:1;min-width:0}
.hero h1{font-size:25px;font-weight:700;letter-spacing:.5px;margin-bottom:6px}
.hero-sub{color:rgba(255,255,255,.85);font-size:13.5px;margin-bottom:18px}
.hero-stats{display:flex;gap:10px;flex-wrap:wrap}
.hstat{
  background:rgba(255,255,255,.14);border:1px solid rgba(255,255,255,.22);
  border-radius:13px;padding:9px 16px;backdrop-filter:blur(4px);min-width:104px;
  flex:1 1 0;
}
.hstat b{display:block;font-size:19px;font-weight:700;line-height:1.3;letter-spacing:.4px}
.hstat span{font-size:11.5px;color:rgba(255,255,255,.8);white-space:nowrap}
.hero-ring{position:relative;z-index:1;flex:0 0 auto}
.ring{
  width:148px;height:148px;border-radius:50%;display:grid;place-items:center;
  background:conic-gradient(#fff calc(var(--pct) * 1%), rgba(255,255,255,.22) 0);
  transition:--pct .6s;
}
.ring-inner{
  width:118px;height:118px;border-radius:50%;background:rgba(94,96,232,.92);
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2px;
  box-shadow:inset 0 0 24px rgba(0,0,0,.12);
}
.ring-inner b{font-size:27px;font-weight:700;line-height:1}
.ring-inner span{font-size:11.5px;color:rgba(255,255,255,.8)}

/* ================= 模式卡片 ================= */
.seg{display:inline-flex;background:#eaeef8;padding:3px;border-radius:11px;gap:2px}
.seg-btn{padding:6px 13px;border-radius:9px;font-size:13px;color:var(--ink-2);transition:.16s}
.seg-btn.active{background:#fff;color:var(--primary);font-weight:600;box-shadow:0 2px 6px rgba(24,35,84,.1)}

.mode-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.mode-card{
  position:relative;background:var(--card);border-radius:var(--radius);padding:20px 20px 18px;
  box-shadow:var(--shadow);border:1px solid transparent;transition:.2s;text-align:left;overflow:hidden;
  display:flex;flex-direction:column;gap:4px;
}
.mode-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-h);border-color:#dfe4f5}
.mode-card::after{
  content:"";position:absolute;right:-40px;top:-40px;width:110px;height:110px;border-radius:50%;
  background:var(--accent-l,#eef1ff);opacity:.65;transition:.25s;
}
.mode-card:hover::after{transform:scale(1.18)}
.mode-ico{
  position:relative;z-index:1;width:46px;height:46px;border-radius:14px;display:grid;place-items:center;
  font-size:22px;background:var(--accent-l,#eef1ff);margin-bottom:8px;
}
.mode-card h3{position:relative;z-index:1;font-size:16px;font-weight:650;letter-spacing:.3px}
.mode-card p{position:relative;z-index:1;font-size:12.5px;color:var(--muted);line-height:1.6}
.mode-foot{position:relative;z-index:1;display:flex;align-items:center;justify-content:space-between;margin-top:12px;font-size:12px;color:var(--muted)}
.mode-go{font-weight:600;color:var(--primary);font-size:13px}
.mode-card.exam{background:linear-gradient(135deg,#fff8ef,#fff);}
.mode-card.exam .mode-ico{background:#fef3e2}
.mode-card.wrong{background:linear-gradient(135deg,#fff5f5,#fff);}
.mode-card.wrong .mode-ico{background:#fdeced}
.mode-card.is-empty{opacity:.7;cursor:not-allowed}
.mode-card.is-empty:hover{transform:none;box-shadow:var(--shadow);border-color:transparent}
.mode-card.is-empty .mode-go{color:var(--muted);font-weight:500}

.bank-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.bank-item{
  background:var(--card);border-radius:15px;padding:16px 18px;box-shadow:var(--shadow);
  display:flex;align-items:center;gap:12px;
}
.bank-item .bi-ico{width:38px;height:38px;border-radius:11px;display:grid;place-items:center;font-size:18px;background:var(--primary-l)}
.bank-item b{display:block;font-size:19px;line-height:1.2;font-weight:700}
.bank-item span{font-size:12px;color:var(--muted)}

/* ================= 练习 ================= */
.practice-bar{display:flex;align-items:center;gap:14px;margin-bottom:18px}
.link-btn{font-size:13.5px;color:var(--muted);padding:6px 2px;transition:.16s;white-space:nowrap}
.link-btn:hover{color:var(--primary)}
.pbar{flex:1;height:8px;background:#e6eaf5;border-radius:99px;overflow:hidden;min-width:60px}
.pbar-fill{height:100%;width:0;border-radius:99px;background:linear-gradient(90deg,#5b6cf8,#9a5cf0);transition:width .3s ease}
.pbar-text{font-size:13px;color:var(--muted);font-variant-numeric:tabular-nums;white-space:nowrap}

.qcard{background:var(--card);border-radius:var(--radius);padding:26px 28px;box-shadow:var(--shadow)}
.qhead{display:flex;align-items:center;gap:8px;margin-bottom:16px;flex-wrap:wrap}
.chip{
  display:inline-block;padding:3px 10px;border-radius:8px;font-size:11.5px;font-weight:600;letter-spacing:.3px;
  background:var(--primary-l);color:var(--primary);
}
.chip-cat{background:#f1f3f9;color:var(--ink-2)}
.chip-exam{background:#fef3e2;color:#b45309}
.chip.single{background:#eef1ff;color:#4f6ef7}
.chip.multi{background:#f0ebff;color:#7c4dff}
.chip.judge{background:#e7f9f2;color:#0f9d75}
.qidx{margin-left:auto;font-size:13px;color:var(--muted);font-variant-numeric:tabular-nums}
.qstem{font-size:17px;line-height:1.85;font-weight:500;color:var(--ink);margin-bottom:20px;word-break:break-word}
.blank{display:inline-block;width:3.4em;height:1em;border-bottom:2px solid #b9c3e0;margin:0 3px;vertical-align:-1px}
.opts{display:flex;flex-direction:column;gap:11px}
.opt{
  display:flex;align-items:flex-start;gap:13px;width:100%;text-align:left;
  padding:14px 16px;border-radius:14px;border:1.5px solid var(--line);background:#fcfcff;
  transition:.16s;font-size:15px;line-height:1.6;color:var(--ink-2);
}
.opt:hover:not(:disabled){border-color:#c2cdf5;background:#f5f7ff}
.opt-key{
  flex:0 0 26px;width:26px;height:26px;border-radius:9px;display:grid;place-items:center;
  background:#eef1f8;color:var(--ink-2);font-size:13px;font-weight:700;transition:.16s;margin-top:1px;
}
.opt-text{flex:1;padding-top:1px;word-break:break-word}
.opt.is-sel{border-color:var(--primary);background:var(--primary-l)}
.opt.is-sel .opt-key{background:var(--primary);color:#fff}
.opt.is-right{border-color:var(--success);background:var(--success-l)}
.opt.is-right .opt-key{background:var(--success);color:#fff}
.opt.is-wrong{border-color:var(--danger);background:var(--danger-l)}
.opt.is-wrong .opt-key{background:var(--danger);color:#fff}
.opt:disabled{cursor:default}
.opt.is-missed{border-color:var(--success);border-style:dashed;background:#f7fdfa}
.opt.is-missed .opt-key{background:#fff;color:var(--success);box-shadow:inset 0 0 0 1.5px var(--success)}

.qfoot{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:24px;flex-wrap:wrap}
.qfoot-tip{font-size:12.5px;color:var(--muted)}
.qfoot-btns{display:flex;gap:10px;margin-left:auto}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  padding:11px 24px;border-radius:13px;font-size:14.5px;font-weight:600;transition:.18s;
  border:1.5px solid transparent;white-space:nowrap;
}
.btn.primary{background:linear-gradient(135deg,#5b6cf8,#7c5cf7);color:#fff;box-shadow:0 6px 16px rgba(91,108,248,.3)}
.btn.primary:hover{box-shadow:0 8px 22px rgba(91,108,248,.4);transform:translateY(-1px)}
.btn.primary:disabled{background:#c8cfe4;color:#4c5468;box-shadow:none;transform:none;cursor:not-allowed}
.btn.ghost{background:#f2f4fa;color:var(--ink-2)}
.btn.ghost:hover{background:#e9edf8}
.btn.danger-ghost{background:#fdeced;color:var(--danger)}
.btn.danger-ghost:hover{background:#fbdcdd}
.btn.danger{background:var(--danger);color:#fff}
.btn.outline{background:#fff;border-color:var(--line);color:var(--ink-2)}
.btn.outline:hover{border-color:#c2cdf5;color:var(--primary)}
.btn.small{padding:8px 15px;font-size:13px;border-radius:11px}
.btn.block{width:100%}

.feedback{margin-top:20px;border-radius:14px;padding:15px 18px;font-size:14px;line-height:1.75;display:none}
.feedback.show{display:block;animation:fade .22s ease}
.feedback.ok{background:var(--success-l);border:1px solid #b9ecd7;color:#0b7a5b}
.feedback.bad{background:var(--danger-l);border:1px solid #f9c9cb;color:#b91c1c}
.feedback.neutral{background:#f4f6fb;border:1px solid var(--line);color:var(--ink-2)}
.fb-title{font-weight:700;font-size:14.5px;margin-bottom:4px;display:flex;align-items:center;gap:7px}
.fb-body{color:inherit;opacity:.92}
.fb-body b{font-weight:700}

/* ================= 结果 ================= */
.result-card{background:var(--card);border-radius:24px;padding:34px 30px;box-shadow:var(--shadow);max-width:640px;margin:20px auto}
.res-top{display:flex;align-items:center;gap:26px;flex-wrap:wrap;justify-content:center}
.res-ring{
  width:132px;height:132px;flex:0 0 132px;border-radius:50%;display:grid;place-items:center;
  background:conic-gradient(var(--rc,#5b6cf8) calc(var(--pct) * 1%), #eef1f8 0);
}
.res-ring-in{width:106px;height:106px;border-radius:50%;background:#fff;display:flex;flex-direction:column;align-items:center;justify-content:center}
.res-ring-in b{font-size:29px;font-weight:700;line-height:1.1}
.res-ring-in span{font-size:11.5px;color:var(--muted)}
.res-info h2{font-size:21px;font-weight:700;margin-bottom:6px}
.res-info p{font-size:13.5px;color:var(--muted)}
.res-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:26px 0 6px}
.res-stat{background:#f7f9fd;border-radius:13px;padding:13px 8px;text-align:center}
.res-stat b{display:block;font-size:19px;font-weight:700;line-height:1.35;font-variant-numeric:tabular-nums}
.res-stat span{font-size:11.5px;color:var(--muted)}
.res-wrong{margin-top:22px}
.res-wrong h3{font-size:14.5px;font-weight:650;margin-bottom:10px;display:flex;align-items:center;gap:6px}
.res-wrong-list{display:flex;flex-direction:column;gap:8px}
.res-wrong-item{background:#fbfcff;border:1px solid var(--line);border-radius:12px;padding:11px 14px;font-size:13px;cursor:pointer;transition:.15s}
.res-wrong-item:hover{border-color:#c9d3f3;background:#f6f8ff}
.res-wrong-item b{color:var(--danger);font-weight:700;margin-right:8px;font-size:12px;background:#fdeced;padding:1px 7px;border-radius:6px;display:inline-block}
.res-wrong-item .answ{color:var(--muted);font-size:12px;margin-top:3px}
.res-btns{display:flex;gap:10px;margin-top:26px;flex-wrap:wrap;justify-content:center}

/* ================= 考试 ================= */
.exam-top{
  display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:16px;flex-wrap:wrap;
  background:linear-gradient(120deg,#2c3452,#3b2f5e);border-radius:16px;padding:13px 18px;color:#fff;
  box-shadow:0 10px 26px rgba(44,52,82,.24);
}
.exam-top-left{display:flex;align-items:center;gap:12px}
.exam-top-right{display:flex;align-items:center;gap:10px}
.timer{
  font-variant-numeric:tabular-nums;font-size:18px;font-weight:700;letter-spacing:1px;
  background:rgba(255,255,255,.12);padding:5px 13px;border-radius:10px;border:1px solid rgba(255,255,255,.16);
}
.timer.warn{background:rgba(239,68,68,.85);animation:blink 1s infinite}
@keyframes blink{50%{opacity:.55}}
.exam-layout{display:grid;grid-template-columns:1fr 236px;gap:18px;align-items:start}
.answer-sheet{background:var(--card);border-radius:var(--radius);padding:18px;box-shadow:var(--shadow);position:sticky;top:86px}
.answer-sheet.collapsed{display:none}
.answer-sheet h3{font-size:14px;font-weight:650;margin-bottom:12px}
.sheet-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:7px;margin-bottom:14px;max-height:340px;overflow:auto}
.sheet-cell{
  aspect-ratio:1;border-radius:9px;background:#f2f4fa;color:var(--ink-2);font-size:12.5px;font-weight:600;
  display:grid;place-items:center;transition:.15s;border:1.5px solid transparent;
}
.sheet-cell:hover{background:#e9edf8}
.sheet-cell.done{background:#e7edff;color:var(--primary)}
.sheet-cell.cur{border-color:var(--primary);background:#fff;color:var(--primary);box-shadow:0 0 0 2px rgba(79,110,247,.18)}
.sheet-legend{display:flex;gap:12px;font-size:11.5px;color:var(--muted);margin-bottom:14px;flex-wrap:wrap}
.sheet-legend span{display:flex;align-items:center;gap:4px}
.lg{width:11px;height:11px;border-radius:4px;display:inline-block;background:#e7edff}
.lg-cur{background:#fff;border:1.5px solid var(--primary)}
.lg-todo{background:#f2f4fa}

/* ================= 错题本 ================= */
.book-meta{font-size:13px;color:var(--muted);margin:2px 0 16px}
.wrong-list{display:flex;flex-direction:column;gap:12px}
.wrong-item{
  background:var(--card);border-radius:16px;padding:18px 20px;box-shadow:var(--shadow);
  display:flex;gap:16px;align-items:flex-start;transition:.18s;cursor:pointer;border:1.5px solid transparent;
}
.wrong-item:hover{border-color:#dfe4f5;box-shadow:var(--shadow-h)}
.wrong-idx{
  flex:0 0 38px;width:38px;height:38px;border-radius:11px;background:#fdeced;color:var(--danger);
  display:grid;place-items:center;font-weight:700;font-size:13px;
}
.wrong-body{flex:1;min-width:0}
.wrong-stem{font-size:14.5px;font-weight:500;line-height:1.7;margin-bottom:6px;word-break:break-word}
.wrong-tags{display:flex;gap:7px;align-items:center;flex-wrap:wrap;font-size:11.5px;color:var(--muted)}
.tag{padding:2px 8px;border-radius:7px;background:#f2f4fa;color:var(--ink-2);font-size:11px;font-weight:600}
.tag.bad{background:#fdeced;color:var(--danger)}
.tag.ok{background:var(--success-l);color:#0f9d75}
.wrong-side{display:flex;flex-direction:column;gap:6px;flex:0 0 auto;align-items:flex-end}
.empty{text-align:center;padding:70px 20px;color:var(--muted)}
.empty .big{font-size:44px;margin-bottom:10px;opacity:.65}
.empty p{font-size:14px}

/* ================= 后台 ================= */
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.stat-card{
  background:var(--card);border-radius:16px;padding:18px 20px;box-shadow:var(--shadow);position:relative;overflow:hidden;
}
.stat-card::after{content:"";position:absolute;right:-26px;top:-26px;width:80px;height:80px;border-radius:50%;background:var(--primary-l);opacity:.6}
.stat-card b{position:relative;display:block;font-size:26px;font-weight:700;line-height:1.3;font-variant-numeric:tabular-nums}
.stat-card b i{font-size:14px;font-style:normal;font-weight:600;color:var(--muted);margin-left:2px}
.stat-card b .v-dur{font-size:19px;letter-spacing:0;white-space:nowrap}
.stat-card span{position:relative;font-size:12.5px;color:var(--muted)}
.stat-card.hl::after{background:#e7f9f2}
.stat-card.hl b{color:var(--success)}

.admin-cols{display:grid;grid-template-columns:1.35fr 1fr;gap:16px;margin-top:16px}
.panel{background:var(--card);border-radius:16px;padding:20px 22px;box-shadow:var(--shadow);margin-top:16px}
.admin-cols .panel{margin-top:0}
.panel h3{font-size:14.5px;font-weight:650;margin-bottom:16px}
.chart{display:flex;align-items:flex-end;gap:10px;height:150px;padding-top:10px}
.chart-col{flex:1;display:flex;flex-direction:column;align-items:center;gap:7px;height:100%;justify-content:flex-end}
.chart-bar{
  width:100%;max-width:40px;border-radius:7px 7px 3px 3px;background:linear-gradient(180deg,#7c8cf9,#5b6cf8);
  min-height:5px;transition:height .5s cubic-bezier(.2,.8,.3,1);position:relative;
}
.chart-bar.zero{background:#e6eaf5}
.chart-bar b{position:absolute;top:-19px;left:50%;transform:translateX(-50%);font-size:11px;color:var(--muted);font-weight:600}
.chart-lbl{font-size:11.5px;color:var(--muted);white-space:nowrap}
.by-type{display:flex;flex-direction:column;gap:11px}
.bt-row{display:flex;flex-direction:column;gap:5px}
.bt-top{display:flex;justify-content:space-between;font-size:12.5px}
.bt-top b{font-variant-numeric:tabular-nums}
.bt-bar{height:7px;border-radius:99px;background:#eef1f8;overflow:hidden}
.bt-bar i{display:block;height:100%;border-radius:99px;background:linear-gradient(90deg,#5b6cf8,#9a5cf0)}
.table-wrap{overflow-x:auto;margin:0 -6px}
.table{width:100%;border-collapse:collapse;font-size:13px;white-space:nowrap}
.table th{
  text-align:left;font-weight:600;color:var(--muted);font-size:12px;padding:8px 12px;
  border-bottom:1px solid var(--line);position:sticky;top:0;background:#fff;
}
.table td{padding:11px 12px;border-bottom:1px solid #f2f4fa;color:var(--ink-2);font-variant-numeric:tabular-nums}
.table tr:last-child td{border-bottom:none}
.table tbody tr:hover td{background:#fafbff}
.table .pass{color:var(--success);font-weight:600}
.table .fail{color:var(--danger);font-weight:600}

/* ================= 弹层 ================= */
.modal-mask{
  position:fixed;inset:0;background:rgba(20,26,48,.45);backdrop-filter:blur(3px);
  display:none;align-items:center;justify-content:center;padding:20px;z-index:90;
}
.modal-mask.show{display:flex;animation:fade .18s ease}
.modal{
  background:#fff;border-radius:20px;padding:26px;max-width:460px;width:100%;
  box-shadow:0 24px 60px rgba(20,26,48,.28);animation:pop .22s cubic-bezier(.2,.9,.3,1.1);
  max-height:86vh;overflow:auto;
}
@keyframes pop{from{transform:scale(.94) translateY(10px);opacity:0}to{transform:none;opacity:1}}
.modal h3{font-size:18px;font-weight:700;margin-bottom:6px}
.modal .sub{font-size:13px;color:var(--muted);margin-bottom:18px}
.modal .field{margin-bottom:16px}
.modal .field-label{font-size:12.5px;font-weight:600;color:var(--ink-2);margin-bottom:8px}
.modal .opts-row{display:flex;gap:8px;flex-wrap:wrap}
.pick{
  padding:8px 16px;border-radius:11px;border:1.5px solid var(--line);font-size:13.5px;background:#fbfcff;
  transition:.15s;color:var(--ink-2);
}
.pick:hover{border-color:#c9d3f3}
.pick.active{border-color:var(--primary);background:var(--primary-l);color:var(--primary);font-weight:600}
.modal-btns{display:flex;gap:10px;justify-content:flex-end;margin-top:22px}
.detail-q{font-size:14.5px;line-height:1.8;margin-bottom:14px;font-weight:500}
.detail-opts{display:flex;flex-direction:column;gap:7px;margin-bottom:14px}
.detail-opt{font-size:13.5px;padding:9px 13px;border-radius:10px;background:#f8f9fd;color:var(--ink-2);border:1.5px solid transparent}
.detail-opt.right{background:var(--success-l);border-color:#b9ecd7;color:#0b7a5b;font-weight:600}
.detail-ans{font-size:13px;color:var(--muted);background:#f7f9fd;border-radius:10px;padding:10px 13px;line-height:1.7}

/* ================= Toast ================= */
.toast{
  position:fixed;left:50%;bottom:38px;transform:translate(-50%,20px);opacity:0;pointer-events:none;
  background:rgba(27,34,51,.93);color:#fff;padding:11px 22px;border-radius:13px;font-size:13.5px;
  z-index:120;transition:.26s;box-shadow:0 10px 26px rgba(0,0,0,.2);
}
.toast.show{opacity:1;transform:translate(-50%,0)}

/* ================= 响应式 ================= */
@media (max-width:900px){
  .mode-grid{grid-template-columns:repeat(2,1fr)}
  .bank-grid{grid-template-columns:repeat(2,1fr)}
  .stat-grid{grid-template-columns:repeat(2,1fr)}
  .admin-cols{grid-template-columns:1fr}
  .exam-layout{grid-template-columns:1fr}
  .answer-sheet{position:static;order:2}
  .answer-sheet.collapsed{display:none}
  .sheet-grid{grid-template-columns:repeat(8,1fr);max-height:none}
  .brand-text small{display:none}
}
@media (max-width:640px){
  .wrap{padding:0 14px}
  .topbar-inner{height:60px}
  .brand-text b{font-size:14.5px}
  .brand-text small{display:none}
  .brand-logo{width:35px;height:35px;flex-basis:35px;font-size:17px;border-radius:11px}
  .nav-btn{padding:7px 11px;font-size:13px}
  .screen{padding:18px 0 60px}
  .hero{flex-direction:column;align-items:flex-start;padding:24px 22px;border-radius:20px;gap:18px}
  .hero h1{font-size:20px}
  .hero-ring{align-self:center}
  .ring{width:120px;height:120px}
  .ring-inner{width:96px;height:96px}
  .ring-inner b{font-size:22px}
  .mode-grid{grid-template-columns:1fr;gap:12px}
  .mode-card{padding:16px 17px}
  .qcard{padding:20px 18px;border-radius:16px}
  .qstem{font-size:16px;line-height:1.8}
  .opt{padding:12px 13px;font-size:14.5px}
  .qfoot-btns{width:100%}
  .qfoot-btns .btn{flex:1}
  .res-stats{grid-template-columns:repeat(2,1fr)}
  .result-card{padding:24px 20px}
  .stat-grid{grid-template-columns:repeat(2,1fr);gap:10px}
  .stat-card{padding:14px 13px}
  .stat-card b{font-size:20px}
  .stat-card b i{font-size:12.5px}
  .blank{width:2.4em}
  .exam-top{padding:11px 13px;border-radius:14px}
  .timer{font-size:16px;padding:4px 10px}
  .sheet-grid{grid-template-columns:repeat(6,1fr)}
  .page-head h1{font-size:20px}
  .section-head{margin:22px 0 12px}
  .hero-stats{gap:8px}
  .hstat{flex:1;min-width:0;padding:8px 12px}
  .hstat b{font-size:17px}
}
/* 窄屏手机（≤430px）：顶栏品牌与导航必须都放得下，hero 统计改 2×2 */
@media (max-width:430px){
  .topbar-inner{gap:8px;padding:0 14px}
  .brand{gap:9px}
  .brand-logo{width:32px;height:32px;flex-basis:32px;font-size:15px;border-radius:10px}
  .brand-text b{font-size:13px;letter-spacing:0}
  .nav{gap:3px;padding:3px}
  .nav-btn{padding:6px 7px;font-size:12.5px}
  .hero-stats{display:grid;grid-template-columns:1fr 1fr;gap:8px}
  .hstat{padding:8px 11px}
  .hstat b{font-size:18px}
  .hstat span{font-size:11px}
}