:root{--bg:#fafafa;--fg:#111;--muted:#6b6b6b;--line:#e4e4e4;--soft:#f1f1f1;--card:#fff;--accent:#111;--r:12px;--side:268px;--top:58px}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.75 -apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",sans-serif}
a{color:inherit}
.top{position:sticky;top:0;z-index:30;height:var(--top);display:flex;align-items:center;gap:12px;padding:0 18px;background:rgba(255,255,255,.92);backdrop-filter:saturate(1.4) blur(10px);border-bottom:1px solid var(--line)}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font-weight:700;letter-spacing:.02em;white-space:nowrap}
.logo{display:inline-grid;place-items:center;width:30px;height:30px;border-radius:8px;background:#111;color:#fff;font-size:15px}
.icon-btn{border:0;background:transparent;font-size:20px;width:38px;height:38px;border-radius:8px;cursor:pointer;color:var(--fg)}
.icon-btn:hover{background:var(--soft)}
#menuBtn{display:none}
.search-trigger{margin-left:auto;display:flex;align-items:center;justify-content:space-between;gap:16px;min-width:280px;height:38px;padding:0 10px 0 14px;border:1px solid var(--line);border-radius:10px;background:#fff;color:var(--muted);cursor:pointer;font:inherit;font-size:14px}
.search-trigger kbd{font:12px ui-monospace,monospace;border:1px solid var(--line);border-radius:5px;padding:1px 6px;background:var(--soft)}
.layout{display:flex;max-width:1280px;margin:0 auto}
.side{position:sticky;top:var(--top);height:calc(100vh - var(--top));width:var(--side);flex:0 0 var(--side);overflow:auto;padding:18px 12px 40px;border-right:1px solid var(--line)}
.side h6{margin:18px 10px 6px;font-size:12px;color:var(--muted);font-weight:600;letter-spacing:.08em}
.side a{display:flex;align-items:center;gap:10px;padding:7px 10px;border-radius:8px;text-decoration:none;font-size:15px}
.side a:hover{background:var(--soft)}
.side a.on{background:#111;color:#fff}
.side a .pct{margin-left:auto;font-size:12px;color:var(--muted)}
.side a.on .pct{color:#ccc}
.side .sub{margin:2px 0 6px 34px;border-left:1px solid var(--line)}
.side .sub a{font-size:13.5px;padding:4px 10px;color:#444}
.side .sub a.done::after{content:"✓";margin-left:auto;color:#111}
main{flex:1;min-width:0;padding:34px 48px 80px;outline:none}
.wrap{max-width:820px}
h1{font-size:34px;line-height:1.3;margin:0 0 10px;letter-spacing:-.01em}
h2{font-size:24px;line-height:1.4;margin:0 0 14px}
h3{font-size:19px;margin:0 0 10px}
h4{font-size:17px;margin:26px 0 8px}
.lead{font-size:18px;color:#333;margin:0 0 24px}
.muted{color:var(--muted);font-size:14px}
.eyebrow{font-size:13px;letter-spacing:.12em;color:var(--muted);text-transform:uppercase;margin-bottom:6px}
.hero{padding:26px 0 30px;border-bottom:1px solid var(--line);margin-bottom:28px}
.hero h1{font-size:40px}
.stats{display:flex;flex-wrap:wrap;gap:28px;margin-top:18px}
.stats div b{display:block;font-size:26px}
.stats div span{font-size:13px;color:var(--muted)}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:14px}
.card{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:18px;text-decoration:none;transition:border-color .15s,transform .15s}
.card:hover{border-color:#111;transform:translateY(-2px)}
.card .ic{font-size:24px}
.card h3{margin:8px 0 4px;font-size:17px}
.card p{margin:0;font-size:14px;color:var(--muted);line-height:1.6}
.bar{height:4px;background:var(--soft);border-radius:4px;margin-top:12px;overflow:hidden}
.bar i{display:block;height:100%;background:#111;border-radius:4px}
.sec{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:26px 28px;margin:0 0 18px;scroll-margin-top:calc(var(--top) + 14px)}
.sec h2{display:flex;align-items:baseline;gap:10px}
.sec h2 .n{font-size:14px;color:var(--muted);font-weight:500}
.sec p,.sec li{color:#222}
.sec ul,.sec ol{padding-left:1.3em}
.sec li{margin:4px 0}
.mark{margin-top:18px;display:flex;justify-content:flex-end}
.btn{display:inline-flex;align-items:center;gap:6px;border:1px solid #111;background:#fff;color:#111;border-radius:999px;padding:7px 16px;font:inherit;font-size:14px;cursor:pointer;text-decoration:none}
.btn:hover{background:var(--soft)}
.btn.solid{background:#111;color:#fff}
.btn.solid:hover{background:#333}
.tblwrap{overflow-x:auto;margin:12px 0;-webkit-overflow-scrolling:touch}
.tbl{width:100%;border-collapse:collapse;font-size:14.5px}
.tbl th,.tbl td{border-bottom:1px solid var(--line);padding:9px 10px;text-align:left;vertical-align:top}
.tbl th{background:var(--soft);font-weight:600;white-space:nowrap}
.tbl tr.grp td{background:#111;color:#fff;font-weight:600;font-size:13px;padding:6px 10px}
.tip,.warn,.formula{border-radius:10px;padding:14px 16px;margin:16px 0;font-size:15px}
.tip{background:var(--soft);border-left:3px solid #111}
.warn{background:#fff;border:1px solid #111}
.warn::before{content:"⚠️ ";}
.formula{background:#fff;border:1px dashed #999;font-family:inherit}
.formula p{margin:4px 0}
.qa{border:1px solid var(--line);border-radius:10px;padding:12px 16px;margin:10px 0}
.qa .q{font-weight:600;margin:0 0 6px}
.qa .q::before{content:"客户：";color:var(--muted);font-weight:500}
.qa .a{margin:0;color:#333}
.qa .a::before{content:"参考：";color:var(--muted)}
.fig{margin:16px 0;padding:16px;border:1px solid var(--line);border-radius:10px;background:#fff;color:#111}
.fig svg{width:100%;height:auto;display:block;max-height:320px}
.fig figcaption{font-size:13px;color:var(--muted);text-align:center;margin-top:8px}
.pager{display:flex;justify-content:space-between;gap:12px;margin-top:28px}
.pager a{flex:1;border:1px solid var(--line);border-radius:var(--r);padding:14px 18px;text-decoration:none;background:#fff}
.pager a:hover{border-color:#111}
.pager small{display:block;color:var(--muted)}
.pager .next{text-align:right}
.quiz{background:#fff;border:1px solid #111;border-radius:var(--r);padding:24px 28px;margin-top:24px}
.qitem{padding:16px 0;border-bottom:1px solid var(--line)}
.qitem:last-of-type{border-bottom:0}
.qitem .qt{font-weight:600;margin-bottom:8px}
.opts{display:grid;gap:8px}
.opt{text-align:left;border:1px solid var(--line);background:#fff;border-radius:8px;padding:9px 12px;font:inherit;font-size:15px;cursor:pointer;color:var(--fg)}
.opt:hover:not(:disabled){border-color:#111}
.opt.right{border-color:#111;background:#111;color:#fff}
.opt.wrong{border-color:#999;background:var(--soft);text-decoration:line-through;color:#777}
.opt:disabled{cursor:default}
.exp{margin-top:8px;font-size:14px;background:var(--soft);padding:10px 12px;border-radius:8px}
.score{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-top:14px;font-weight:600}
.gl-tools{display:flex;gap:10px;flex-wrap:wrap;margin:10px 0 18px}
.gl-tools input{flex:1;min-width:200px;height:42px;border:1px solid var(--line);border-radius:10px;padding:0 14px;font:inherit;background:#fff}
.chips{display:flex;gap:6px;flex-wrap:wrap}
.chip{border:1px solid var(--line);background:#fff;border-radius:999px;padding:5px 12px;font:inherit;font-size:13px;cursor:pointer}
.chip.on{background:#111;color:#fff;border-color:#111}
.gl{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:10px}
.term{background:#fff;border:1px solid var(--line);border-radius:10px;padding:14px 16px}
.term b{font-size:16px}
.term .en{font-size:12.5px;color:var(--muted);margin-left:6px}
.term .cat{float:right;font-size:11.5px;border:1px solid var(--line);border-radius:999px;padding:0 8px;color:var(--muted)}
.term p{margin:6px 0 0;font-size:14px;color:#333;line-height:1.65}
mark{background:#111;color:#fff;padding:0 2px;border-radius:2px}
.scrim{display:none;position:fixed;inset:0;background:rgba(0,0,0,.35);z-index:40}
.scrim.show{display:block}
.search-modal{display:none;position:fixed;z-index:50;left:50%;top:9vh;transform:translateX(-50%);width:min(680px,94vw);max-height:78vh;background:#fff;border-radius:14px;box-shadow:0 20px 60px rgba(0,0,0,.25);overflow:hidden;flex-direction:column}
.search-modal.show{display:flex}
.search-box{display:flex;align-items:center;gap:6px;border-bottom:1px solid var(--line);padding:8px 10px 8px 16px}
.search-box input{flex:1;border:0;outline:0;font:inherit;font-size:17px;height:44px;background:transparent}
.search-results{overflow:auto;padding:8px}
.sr{display:block;padding:10px 12px;border-radius:8px;text-decoration:none}
.sr:hover,.sr.active{background:var(--soft)}
.sr .t{font-weight:600;font-size:15px}
.sr .k{font-size:11.5px;border:1px solid var(--line);border-radius:999px;padding:0 7px;margin-right:6px;color:var(--muted);font-weight:500}
.sr .s{font-size:13.5px;color:var(--muted);margin-top:2px;line-height:1.55}
.empty{padding:24px;text-align:center;color:var(--muted)}
.foot{margin-top:50px;padding-top:18px;border-top:1px solid var(--line);font-size:13px;color:var(--muted)}
@media (max-width:900px){
  #menuBtn{display:inline-block}
  .side{position:fixed;left:0;top:0;height:100%;z-index:45;background:#fff;transform:translateX(-102%);transition:transform .2s;box-shadow:0 0 30px rgba(0,0,0,.15);padding-top:20px}
  .side.open{transform:none}
  main{padding:22px 16px 70px}
  .search-trigger{min-width:0;flex:1;max-width:260px}
  .search-trigger span{overflow:hidden;white-space:nowrap;text-overflow:ellipsis}
  .search-trigger kbd{display:none}
  .brand span:last-child{display:none}
  h1,.hero h1{font-size:28px}
  .sec,.quiz{padding:18px 16px}
  .tbl{font-size:13.5px}
  .tbl td,.tbl th{min-width:92px}
  .fig.wide{overflow-x:auto}
  .fig.wide svg{min-width:600px}
  .fig.wide figcaption::after{content:'（可左右滑动查看）'}
  .pager{flex-direction:column}
  .stats{gap:18px}
}