:root{--bg:#f6f8fb;--fg:#1b2430;--muted:#5d6b7c;--pri:#1d3557;--pri2:#2b4c7e;--acc:#e63946;--ok:#1f8a4c;--okbg:#e6f5ec;--ng:#c0392b;--ngbg:#fdecea;--card:#fff;--bd:#dfe5ec;--warn:#9a6700;--warnbg:#fff6dd;--r:12px}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.7 -apple-system,BlinkMacSystemFont,"PingFang SC","PingFang TC","Hiragino Sans","Noto Sans CJK SC","Noto Sans CJK TC","Microsoft YaHei","Microsoft JhengHei",sans-serif}
a{color:var(--pri2)}
.wrap{max-width:860px;margin:0 auto;padding:0 16px}
.skip{position:absolute;left:-999px}.skip:focus{left:8px;top:8px;background:#fff;padding:6px 10px;z-index:99}
.top{background:var(--pri);color:#fff;position:sticky;top:0;z-index:20}
.top .wrap{display:flex;align-items:center;justify-content:space-between;gap:8px;padding-top:8px;padding-bottom:4px}
.logo{display:flex;align-items:center;gap:8px;color:#fff;text-decoration:none;font-weight:700}
.logo i{display:inline-grid;place-items:center;width:28px;height:28px;border-radius:8px;background:#fff;color:var(--pri);font-style:normal}
.lang{display:flex;gap:4px;font-size:13px}
.lang a{color:#cfd9e8;text-decoration:none;padding:3px 8px;border-radius:99px;border:1px solid rgba(255,255,255,.3)}
.lang a[aria-current]{background:#fff;color:var(--pri)}
.menu{display:flex;gap:2px;overflow-x:auto;white-space:nowrap;padding-bottom:6px;scrollbar-width:none}
.menu a{color:#e6edf7;text-decoration:none;padding:6px 10px;border-radius:8px;font-size:14px}
.menu a[aria-current]{background:rgba(255,255,255,.18);font-weight:700}
main{padding-top:16px;padding-bottom:40px}
h1{font-size:1.55rem;line-height:1.35;margin:.4em 0 .3em;color:var(--pri)}
h2{font-size:1.2rem;margin:1.6em 0 .5em;color:var(--pri)}
h3{font-size:1.05rem}
.lead{font-size:1.05rem;color:#33414f}
.muted{color:var(--muted)}.small{font-size:.85rem}
.crumbs{font-size:13px;color:var(--muted);margin:2px 0 6px}.crumbs a{color:var(--muted)}
.hero{padding:8px 0 4px}
.cta{display:flex;flex-wrap:wrap;gap:10px;margin:14px 0}
.btn{display:inline-block;background:var(--pri);color:#fff;text-decoration:none;border:0;border-radius:10px;padding:11px 18px;font-size:1rem;cursor:pointer;font-family:inherit;min-height:44px}
.btn:hover{background:var(--pri2)}
.btn.alt{background:var(--acc)}.btn.alt:hover{background:#c92f3b}
.btn.ghost{background:#fff;color:var(--pri);border:1px solid var(--pri)}
.btn.small{padding:6px 12px;font-size:.9rem;min-height:36px}
.btn[disabled]{opacity:.5;cursor:not-allowed}
.card{background:var(--card);border:1px solid var(--bd);border-radius:var(--r);padding:14px 16px;margin:12px 0}
.callout{background:var(--warnbg);border:1px solid #f1dca0;border-radius:var(--r);padding:10px 14px;margin:14px 0;font-size:.93rem}
.callout.news{background:#eaf2ff;border-color:#c5d9f7}.callout.news h2{margin:0 0 4px;font-size:1.05rem}.callout ul{margin:0;padding-left:1.2em}
.tag{display:inline-block;font-size:.72rem;padding:1px 8px;border-radius:99px;vertical-align:middle;font-weight:600}
.tag.ok{background:var(--okbg);color:var(--ok)}.tag.warn{background:var(--warnbg);color:var(--warn);border:1px solid #f1dca0}
.grid{display:grid;gap:10px}
.grid.cats{grid-template-columns:repeat(2,1fr)}
.grid.guides{grid-template-columns:1fr}
a.cat,a.guide{display:block;background:#fff;border:1px solid var(--bd);border-radius:var(--r);padding:12px 14px;text-decoration:none;color:var(--fg)}
a.cat:hover,a.guide:hover{border-color:var(--pri2)}
a.cat strong,a.guide strong{display:block;color:var(--pri)}
a.cat span,a.guide span{display:block;font-size:.82rem;color:var(--muted)}
a.cat em{font-style:normal;font-size:.8rem;color:var(--acc)}
.feat{list-style:none;padding:0;display:grid;gap:8px}.feat li{background:#fff;border:1px solid var(--bd);border-radius:var(--r);padding:10px 14px}.feat strong{display:block;color:var(--pri)}
details{background:#fff;border:1px solid var(--bd);border-radius:var(--r);margin:8px 0;padding:0}
summary{cursor:pointer;padding:12px 14px;font-weight:600}
details .ans{padding:0 14px 12px}
.qitem summary{font-weight:500}.num{display:inline-block;min-width:1.8em;color:var(--acc);font-weight:700}
.jaq{color:var(--muted);font-size:.9rem;margin:.2em 0}
.terms{display:flex;flex-wrap:wrap;gap:6px;font-size:.88rem}.terms span{background:#eef3fa;border-radius:8px;padding:2px 8px}
.biglist{padding-left:1.2em}.biglist li{margin:10px 0}
.tablewrap{overflow-x:auto}
table{border-collapse:collapse;width:100%;background:#fff;font-size:.93rem}
th,td{border:1px solid var(--bd);padding:8px 10px;text-align:left;vertical-align:top}
th{background:#eef3fa;color:var(--pri)}
.search{width:100%;padding:10px 12px;border:1px solid var(--bd);border-radius:10px;font-size:1rem}
.steps{list-style:none;padding:0;counter-reset:s}
.step{background:#fff;border:1px solid var(--bd);border-radius:var(--r);padding:4px 16px 10px;margin:12px 0}
.step h2{margin:.6em 0 .3em;font-size:1.1rem}.step .n{display:inline-block;background:var(--pri);color:#fff;border-radius:99px;padding:0 10px;font-size:.8rem;margin-right:6px;vertical-align:middle}
.checklist{list-style:none;padding:0}.checklist li{background:#fff;border:1px solid var(--bd);border-radius:var(--r);margin:8px 0}
.checklist label{display:flex;gap:12px;padding:12px 14px;cursor:pointer;align-items:flex-start}
.checklist input{width:22px;height:22px;margin-top:3px;flex:none}
.checklist li.done{background:var(--okbg);border-color:#b8e2c8}
.checks li{margin:6px 0}
.note{color:var(--muted);font-style:italic}
footer{border-top:1px solid var(--bd);background:#fff;padding:16px 0;font-size:.85rem;color:var(--muted)}footer a{color:var(--muted)}
.disc{margin:0 0 8px}
.prose h2{border-left:4px solid var(--acc);padding-left:10px}
.root .center{text-align:center;padding-top:12vh}.root h1 small{display:block;font-size:.9rem;color:var(--muted);font-weight:400}.root .cta{justify-content:center}
/* quiz */
.qwrap .bar{display:flex;justify-content:space-between;align-items:center;font-size:.9rem;color:var(--muted);margin-bottom:6px;gap:8px}
.pbar{height:6px;background:#e3e9f1;border-radius:99px;overflow:hidden;margin-bottom:12px}.pbar i{display:block;height:100%;background:var(--pri2);width:0}
.qcard{background:#fff;border:1px solid var(--bd);border-radius:var(--r);padding:16px}
.qtag{display:inline-block;font-size:.75rem;background:#eef3fa;color:var(--pri);padding:1px 10px;border-radius:99px;margin-bottom:8px}
.qtext{font-size:1.12rem;font-weight:600;margin:.2em 0 .4em}
.qja{font-size:.92rem;color:var(--muted);margin:0 0 .6em;padding-left:10px;border-left:3px solid var(--bd)}
.ox{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:14px 0 4px}
.ox button{font-size:1.6rem;font-weight:700;padding:14px 0;border-radius:12px;border:2px solid var(--bd);background:#fff;cursor:pointer;min-height:64px;font-family:inherit}
.ox button small{display:block;font-size:.75rem;font-weight:500;color:var(--muted)}
.ox .o{color:var(--ok);border-color:#a8d8bb}.ox .x{color:var(--ng);border-color:#f0b4ad}
.ox button.sel{outline:3px solid var(--pri2);background:#eef3fa}
.ox button.right{background:var(--okbg);border-color:var(--ok)}.ox button.bad{background:var(--ngbg);border-color:var(--ng)}
.ox button[disabled]{cursor:default}
.fb{margin-top:12px;border-radius:10px;padding:10px 14px}.fb.ok{background:var(--okbg);border:1px solid #b8e2c8}.fb.ng{background:var(--ngbg);border:1px solid #f0b4ad}
.fb h3{margin:0 0 4px}
.qnav{display:flex;justify-content:space-between;gap:10px;margin-top:14px}
.chips{display:flex;flex-wrap:wrap;gap:8px;margin:8px 0}
.chip{border:1px solid var(--bd);background:#fff;border-radius:99px;padding:6px 12px;font-size:.9rem;cursor:pointer;font-family:inherit;color:var(--fg)}
.chip[aria-pressed=true]{background:var(--pri);color:#fff;border-color:var(--pri)}
.chip small{opacity:.75;margin-left:4px}
fieldset{border:0;padding:0;margin:14px 0}legend{font-weight:700;color:var(--pri);padding:0;margin-bottom:4px}
.radios{display:flex;flex-wrap:wrap;gap:8px}.radios label{border:1px solid var(--bd);background:#fff;border-radius:10px;padding:8px 12px;cursor:pointer}.radios input{margin-right:6px}
.timer{font-variant-numeric:tabular-nums;font-weight:700;color:var(--pri);font-size:1.05rem}.timer.low{color:var(--acc)}
.qgrid{display:flex;flex-wrap:wrap;gap:6px;margin:10px 0}
.qgrid button{width:36px;height:36px;border-radius:8px;border:1px solid var(--bd);background:#fff;cursor:pointer;font-size:.85rem;font-family:inherit}
.qgrid button.a{background:#dce8f8;border-color:#9bb7de}.qgrid button.cur{outline:2px solid var(--acc)}
.score{font-size:2.4rem;font-weight:800;color:var(--pri);margin:0}.score.pass{color:var(--ok)}.score.fail{color:var(--ng)}
.stats{display:grid;grid-template-columns:repeat(2,1fr);gap:10px;margin:10px 0}.stats div{background:#fff;border:1px solid var(--bd);border-radius:var(--r);padding:10px 12px}.stats b{display:block;font-size:1.3rem;color:var(--pri)}
.rlist .qitem{border-left:4px solid var(--ng)}
.hist{list-style:none;padding:0;margin:6px 0}.hist li{padding:6px 0;border-bottom:1px dashed var(--bd);display:flex;justify-content:space-between;font-size:.93rem}
.linkbtn{background:none;border:0;color:var(--muted);text-decoration:underline;cursor:pointer;font-size:.85rem;font-family:inherit;padding:4px}
.row{display:flex;gap:10px;flex-wrap:wrap;align-items:center}
@media(min-width:640px){.grid.cats{grid-template-columns:repeat(3,1fr)}.grid.guides{grid-template-columns:repeat(2,1fr)}.feat{grid-template-columns:repeat(2,1fr)}h1{font-size:1.9rem}.stats{grid-template-columns:repeat(4,1fr)}}