:root{
  --bg:#f6f7f9; --surface:#fff; --text:#141a22; --muted:#596373; --line:#dde2ea;
  --accent:#0a66c2; --accent-soft:#e6f0fb; --accent-text:#fff;
  --ok:#0f7a4a; --warn-bg:#fff6df; --warn-line:#f0d28a; --warn-text:#5c4300;
  --out-bg:#f0f6fd; --radius:12px; --shadow:0 1px 2px rgba(15,25,40,.06),0 4px 14px rgba(15,25,40,.04);
  --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,"Liberation Mono",monospace;
  --sans:system-ui,-apple-system,"Segoe UI","Apple SD Gothic Neo","Noto Sans KR","Malgun Gothic",Roboto,sans-serif;
  color-scheme:light dark;
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]){
    --bg:#0d1117; --surface:#151b24; --text:#e7ebf1; --muted:#9ba6b6; --line:#273142;
    --accent:#5aa8ff; --accent-soft:#16253a; --accent-text:#0a0f16;
    --ok:#4cc38a; --warn-bg:#2a2210; --warn-line:#6b5415; --warn-text:#f2d58b;
    --out-bg:#111c2b; --shadow:none;
  }
}
:root[data-theme="dark"]{
  --bg:#0d1117; --surface:#151b24; --text:#e7ebf1; --muted:#9ba6b6; --line:#273142;
  --accent:#5aa8ff; --accent-soft:#16253a; --accent-text:#0a0f16;
  --ok:#4cc38a; --warn-bg:#2a2210; --warn-line:#6b5415; --warn-text:#f2d58b;
  --out-bg:#111c2b; --shadow:none;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--text);font:16px/1.7 var(--sans);word-break:keep-all;overflow-wrap:anywhere}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid var(--accent);outline-offset:2px;border-radius:6px}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px}
.skip{position:absolute;left:-999px;top:8px;background:var(--surface);padding:8px 12px;border-radius:8px;z-index:20}
.skip:focus{left:8px}

/* header */
.site-header{background:var(--surface);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:10}
.hd{display:flex;align-items:center;gap:20px;min-height:60px;flex-wrap:wrap;padding:6px 0}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;color:var(--text);font-size:1.08rem}
.brand:hover{text-decoration:none}
.brand svg{width:28px;height:28px;flex:none}
.nav{display:flex;gap:4px;flex-wrap:wrap;margin-left:8px}
.nav a{color:var(--text);padding:6px 12px;border-radius:8px;font-size:.95rem}
.nav a:hover{background:var(--accent-soft);text-decoration:none}
.nav a[aria-current="page"]{background:var(--accent-soft);color:var(--accent);font-weight:600}
.hd-right{margin-left:auto;display:flex;gap:8px;align-items:center}
.lang-menu{position:relative}
.lang-menu summary{list-style:none;cursor:pointer;display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);border-radius:8px;padding:5px 10px;font-size:.88rem;color:var(--text);background:var(--surface);white-space:nowrap}
.lang-menu summary::-webkit-details-marker{display:none}
.lang-menu summary:hover,.lang-menu[open] summary{background:var(--accent-soft)}
.lang-list{position:absolute;right:0;top:calc(100% + 6px);z-index:30;min-width:140px;display:grid;gap:2px;background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:6px;box-shadow:0 8px 24px rgba(0,0,0,.18)}
.lang-list a,.lang-list span{padding:8px 10px;border-radius:6px;font-size:.92rem;color:var(--text)}
.lang-list a:hover{background:var(--accent-soft);text-decoration:none}
.lang-list span{color:var(--muted);font-weight:600}

/* 일본어·중국어: 글꼴과 줄바꿈 (한국어용 keep-all 해제) */
html[lang="ja"] body{font-family:system-ui,-apple-system,"Hiragino Sans","Hiragino Kaku Gothic ProN","Yu Gothic UI","Meiryo","Noto Sans JP",sans-serif;word-break:normal;line-break:strict;overflow-wrap:anywhere}
html[lang="zh-Hans"] body{font-family:system-ui,-apple-system,"PingFang SC","Microsoft YaHei","Noto Sans SC","Source Han Sans SC",sans-serif;word-break:normal;line-break:strict;overflow-wrap:anywhere}
html[lang="ja"] .inp select:not(.u-sel),html[lang="ja"] .inp select.u-sel,html[lang="ja"] .res .v.text{font-family:inherit}

/* layout */
main{padding:28px 0 56px}
h1{font-size:clamp(1.6rem,3.2vw,2.15rem);line-height:1.25;margin:.2em 0 .4em;letter-spacing:-.01em}
h2{font-size:1.35rem;margin:2em 0 .6em;line-height:1.35;letter-spacing:-.005em}
h3{font-size:1.1rem;margin:1.4em 0 .4em}
p{margin:.7em 0}
.lede{font-size:1.08rem;color:var(--muted)}
.crumbs{font-size:.88rem;color:var(--muted);margin-bottom:6px}
.crumbs a{color:var(--muted)}
.crumbs span[aria-hidden]{margin:0 6px}
.meta{font-size:.85rem;color:var(--muted)}

/* cards & grids */
.grid{display:grid;gap:14px;grid-template-columns:repeat(auto-fill,minmax(250px,1fr))}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:16px 18px;box-shadow:var(--shadow);display:block;color:var(--text)}
a.card:hover{border-color:var(--accent);text-decoration:none;transform:translateY(-1px)}
.card h3{margin:0 0 .3em;font-size:1.02rem}
.card p{margin:0;color:var(--muted);font-size:.9rem;line-height:1.55}
.tag{display:inline-block;font-size:.74rem;padding:1px 8px;border-radius:99px;background:var(--accent-soft);color:var(--accent);margin-bottom:6px}
.hero{padding:18px 0 8px}
.hero .lede{margin-bottom:18px}
.search{width:100%;max-width:560px;padding:12px 16px;font:inherit;border:1px solid var(--line);border-radius:10px;background:var(--surface);color:var(--text)}
label.chip{display:inline-flex;align-items:center}
label.chip:has(input:focus-visible){outline:3px solid var(--accent);outline-offset:2px}
.lc-preset{max-width:420px;margin-top:16px}
.lc-preset p{margin:8px 0 0}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin:14px 0 4px}
.chip{border:1px solid var(--line);background:var(--surface);color:var(--text);border-radius:99px;padding:5px 14px;font:inherit;font-size:.9rem;cursor:pointer}
.chip[aria-pressed="true"]{background:var(--accent);color:var(--accent-text);border-color:var(--accent)}
.cat-title{display:flex;align-items:baseline;justify-content:space-between;gap:10px}
[hidden]{display:none!important}
.empty{color:var(--muted);padding:12px 0}

/* calculator */
.calc{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px;margin:18px 0}
.calc-grid{display:grid;gap:14px 18px;grid-template-columns:repeat(auto-fit,minmax(230px,1fr))}
.field label{display:block;font-size:.88rem;color:var(--muted);margin-bottom:4px}
.inp{display:flex;align-items:stretch;border:1px solid var(--line);border-radius:10px;background:var(--surface);overflow:hidden;transition:border-color .15s,box-shadow .15s}
.inp:focus-within{border-color:var(--accent);box-shadow:0 0 0 3px color-mix(in srgb,var(--accent) 35%,transparent)}
.inp input,.inp select{flex:1;min-width:0;font:inherit;font-family:var(--mono);padding:10px 12px;border:0;border-radius:0;background:transparent;color:var(--text)}
.inp input:focus-visible,.inp select:focus-visible{outline:none}
.inp select:not(.u-sel){font-family:var(--sans)}
.inp .u{flex:none;display:flex;align-items:center;padding:0 12px;border-left:1px solid var(--line);background:var(--accent-soft);color:var(--muted);font-size:.88rem;white-space:nowrap}
.inp select.u-sel{flex:none;font-family:var(--sans);font-size:.88rem;padding:0 8px 0 10px;border-left:1px solid var(--line);background:var(--accent-soft);color:var(--text);cursor:pointer}
.res select.u-sel{font:inherit;font-size:.88rem;margin-left:6px;padding:2px 4px;border:1px solid var(--line);border-radius:6px;background:var(--accent-soft);color:var(--muted);cursor:pointer}
.params{margin-bottom:14px;padding-bottom:14px;border-bottom:1px dashed var(--line)}
.results{margin-top:16px;display:grid;gap:10px;grid-template-columns:repeat(auto-fit,minmax(230px,1fr))}
.res{background:var(--out-bg);border:1px solid var(--line);border-radius:10px;padding:10px 14px}
.res .l{font-size:.82rem;color:var(--muted)}
.res .v{font:600 1.35rem/1.35 var(--mono);color:var(--text);cursor:copy;display:inline-block;word-break:break-all}
.res .v.text{font:600 1.02rem/1.5 var(--sans)}
.res .u2{font-size:.88rem;color:var(--muted);margin-left:6px}
.res.ro .v{color:var(--ok)}
.calc-foot{display:flex;flex-wrap:wrap;align-items:center;gap:10px 14px;margin-top:14px}
.calc-foot .meta{margin:0}
.share-btn{font:inherit;font-size:.88rem;padding:8px 14px;border:1px solid var(--line);border-radius:10px;background:var(--surface);color:var(--text);cursor:pointer;transition:border-color .15s,background .15s}
.share-btn:hover{border-color:var(--accent);background:var(--accent-soft)}
.toast{position:fixed;right:16px;bottom:16px;background:var(--text);color:var(--bg);padding:8px 14px;border-radius:8px;font-size:.88rem;opacity:0;transition:opacity .2s;pointer-events:none}
.toast.on{opacity:.95}
.linked-hint{font-size:.85rem;color:var(--muted);margin:0 0 12px}
.formula{background:var(--surface);border:1px solid var(--line);border-left:4px solid var(--accent);border-radius:8px;padding:10px 16px;font-family:var(--mono);font-size:.95rem;line-height:1.9;overflow-x:auto}
.example{background:var(--accent-soft);border-radius:10px;padding:12px 16px;font-size:.95rem}
.tip,.note{background:var(--warn-bg);border:1px solid var(--warn-line);color:var(--warn-text);border-radius:10px;padding:12px 16px;margin:1em 0;font-size:.95rem}
.tip strong{display:block;margin-bottom:2px}
.disclaimer{font-size:.84rem;color:var(--muted);margin-top:24px;padding-top:12px;border-top:1px solid var(--line)}
.ad{margin:24px 0;min-height:90px;text-align:center}
.ad small{display:block;font-size:.72rem;color:var(--muted);margin-bottom:2px}

/* content */
.prose{max-width:none}
.prose ul{padding-left:1.3em}
.prose li{margin:.3em 0}
.tbl{overflow-x:auto;margin:1em 0;border:1px solid var(--line);border-radius:10px;background:var(--surface)}
table{border-collapse:collapse;width:100%;font-size:.93rem}
th,td{padding:9px 14px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--accent-soft);font-weight:600;white-space:nowrap}
tr:last-child td{border-bottom:0}
.tbl.nums table{width:auto;min-width:100%}
.tbl.nums td,.tbl.nums th{white-space:nowrap}
.tbl.nums th[scope="row"]{position:sticky;left:0;z-index:1}
.tbl-note{font-size:.85rem;color:var(--muted);margin:-.4em 0 1em}
dl.terms{margin:0}
dl.terms dt{font-weight:700;margin-top:1.1em;scroll-margin-top:80px}
dl.terms dt small{font-weight:400;color:var(--muted);margin-left:6px}
dl.terms dd{margin:.15em 0 0;color:var(--text)}
.toc{display:flex;gap:8px;flex-wrap:wrap;margin:10px 0 0}
.related{display:flex;gap:10px;flex-wrap:wrap;margin:8px 0}
.related a{border:1px solid var(--line);background:var(--surface);border-radius:99px;padding:5px 14px;font-size:.9rem;color:var(--text)}
.related a:hover{border-color:var(--accent);text-decoration:none}

/* footer */
.site-footer{border-top:1px solid var(--line);background:var(--surface);padding:26px 0;color:var(--muted);font-size:.9rem}
.ft{display:flex;flex-wrap:wrap;gap:12px 28px;justify-content:space-between}
.ft a{color:var(--muted);margin-right:14px}
.ft a:hover{color:var(--accent)}
.ft p{margin:.4em 0}
@media (max-width:640px){
  .wrap{padding:0 16px}.nav{margin-left:0;order:3;width:100%}
  .hd-right{margin-left:auto}.calc{padding:16px}
}
@media print{.site-header,.site-footer,.ad,.search,.chips{display:none}body{background:#fff;color:#000}}
.card p{display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}

/* 시험 도구: 한도 점검표 */
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.wscroll{position:relative;overflow-x:auto;margin:16px 0 8px;border:1px solid var(--line);border-radius:10px}
.wtable{border-collapse:collapse;width:100%;min-width:980px;font-size:.9rem}
.wtable th{background:var(--accent-soft);color:var(--muted);font-weight:600;font-size:.8rem;text-align:left;padding:8px 6px;border-bottom:1px solid var(--line);white-space:nowrap}
.wtable td{padding:4px 4px;border-bottom:1px solid var(--line);vertical-align:middle}
.wtable td input{width:100%;min-width:72px;font:inherit;font-family:var(--mono);padding:6px 8px;border:1px solid var(--line);border-radius:8px;background:var(--surface);color:var(--text)}
.wtable td[data-res]{font-family:var(--mono);white-space:nowrap;padding:4px 8px}
.st{font-family:var(--sans);font-weight:600}
.st-ok{color:var(--ok)}
.st-gray{color:var(--warn-text);background:var(--warn-bg);border-radius:6px}
.st-fail{color:#c0262d}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]) .st-fail{color:#ff8a8f}}
:root[data-theme="dark"] .st-fail{color:#ff8a8f}
.paste{width:100%;font-family:var(--mono);font-size:.88rem;padding:10px;border:1px solid var(--line);border-radius:10px;background:var(--surface);color:var(--text)}
.lc-import{margin-top:16px}.lc-import summary{cursor:pointer;color:var(--accent)}
.draft-banner{margin-top:12px;font-weight:600}

/* theme switch: 해(라이트) ↔ 달(다크) 토글 */
.theme-switch{position:relative;flex:none;width:68px;height:34px;padding:0;border:0;border-radius:99px;cursor:pointer;background:linear-gradient(135deg,#ffd45a,#ff8a3d);box-shadow:inset 0 2px 4px rgba(150,70,0,.3),0 0 0 2px rgba(255,170,60,.55),0 2px 10px rgba(255,140,40,.35);transition:background .4s ease,box-shadow .4s ease}
.theme-switch:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
.theme-switch .ts-stars{position:absolute;left:8px;top:6px;opacity:0;transition:opacity .4s ease}
.theme-switch .knob{position:absolute;top:3px;left:3px;width:28px;height:28px;border-radius:50%;background:radial-gradient(circle at 35% 30%,#fffef0,#ffe27a 70%,#ffcc33);display:grid;place-items:center;box-shadow:0 2px 6px rgba(120,60,0,.4),inset 0 -2px 3px rgba(255,170,0,.4);transition:transform .4s cubic-bezier(.4,.1,.2,1),background .4s ease,box-shadow .4s ease}
.theme-switch .knob svg{grid-area:1/1;transition:opacity .3s ease,transform .4s ease}
.theme-switch .i-sun{filter:drop-shadow(0 0 3px rgba(255,190,0,.7))}
.theme-switch .i-moon{opacity:0;transform:rotate(-50deg) scale(.5)}
.theme-switch[aria-checked="true"]{background:linear-gradient(135deg,#0b1230,#1c1f5c);box-shadow:inset 0 2px 5px rgba(0,0,0,.6),0 0 0 2px #4b7dff,0 0 14px rgba(120,90,255,.55)}
.theme-switch[aria-checked="true"] .ts-stars{opacity:1}
.theme-switch[aria-checked="true"] .knob{transform:translateX(34px);background:radial-gradient(circle at 35% 30%,#2a3a8a,#0d1840 75%);box-shadow:0 0 0 1.5px #6ea8ff,0 0 10px rgba(110,190,255,.6),inset 0 1px 3px rgba(150,200,255,.35)}
.theme-switch[aria-checked="true"] .i-sun{opacity:0;transform:rotate(60deg) scale(.5)}
.theme-switch[aria-checked="true"] .i-moon{opacity:1;transform:none;filter:drop-shadow(0 0 4px rgba(124,200,255,.9))}
@media (prefers-reduced-motion:reduce){.theme-switch,.theme-switch .knob,.theme-switch .knob svg,.theme-switch .ts-stars{transition:none}}
:root[data-theme="dark"] .st-fail{color:#ff8a8f}

/* 줄바꿈 품질: 제목은 균형 있게, 본문은 한 글자 남는 줄 방지 */
h1,h2,h3,.card h3{text-wrap:balance}
p,li,dd,.card p{text-wrap:pretty}

/* 메뉴 옆 네온 선 아이콘: 라이트에서는 진한 색, 다크에서는 네온 색 + 빛 번짐 (EMIC NavNeonIcon과 같은 결) */
.nav a{display:inline-flex;align-items:center;gap:7px}
.nav-ico{flex:none;padding:3px;border-radius:7px;background:linear-gradient(135deg,var(--c1),var(--c2));fill:none;stroke:#fff;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;box-shadow:inset 0 1px 1px rgba(255,255,255,.45),0 1px 3px rgba(0,0,0,.25);transition:transform .15s ease,box-shadow .15s ease}
.nav a:hover .nav-ico,.nav a[aria-current="page"] .nav-ico{transform:translateY(-1px);box-shadow:inset 0 1px 1px rgba(255,255,255,.5),0 0 8px color-mix(in srgb,var(--c2) 60%,transparent)}

/* 짧은 페이지에서도 스크롤바 자리를 항상 확보해, 페이지마다 내용이 좌우로 흔들리지 않게 한다 */
html{overflow-y:scroll;scrollbar-gutter:stable}

.search + .grid{margin-top:22px}

/* 다크모드 전환: 버튼을 누른 순간에만 전체 화면 색이 부드럽게 바뀜 (처음 로딩 때는 적용 안 함) */
html.theme-anim *:not(.theme-switch):not(.theme-switch *),html.theme-anim *::before,html.theme-anim *::after{transition:background-color .4s ease,color .4s ease,border-color .4s ease,box-shadow .4s ease,fill .4s ease,stroke .4s ease!important}
@media (prefers-reduced-motion:reduce){html.theme-anim *{transition:none!important}}

/* ───── 치트시트 (화면 + 인쇄 한 장) ───── */
.cs-sheet{border:1px solid var(--line);border-radius:12px;background:var(--surface);padding:18px 18px 10px;margin:16px 0}
.cs-head{margin:0 0 12px;font-weight:700;font-size:.95rem;color:var(--muted)}
.cs-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:14px 18px;align-items:start}
.cs-box{min-width:0}
.cs-box.wide{grid-column:1/-1}
.cs-box h2{font-size:.9rem;margin:0 0 6px;padding-bottom:4px;border-bottom:2px solid var(--accent);color:var(--text)}
.cs-box table{width:100%;font-size:.84rem;border-collapse:collapse}
.cs-box th,.cs-box td{padding:3px 8px 3px 0;border:0;border-bottom:1px solid var(--line);white-space:nowrap;vertical-align:baseline}
.cs-box th[scope="row"]{background:none;font-weight:600}
.cs-box thead th{background:none;font-size:.78rem;color:var(--muted);font-weight:600}
.cs-box ul{margin:0;padding-left:1.1em;font-size:.84rem}
.cs-box li{margin:3px 0}
.cs-box.mono li{font-family:var(--mono);font-size:.82rem;white-space:nowrap;overflow-x:auto}
.cs-foot{margin:14px 0 4px;font-size:.76rem;color:var(--muted)}

@media print{
  .noprint,header,footer,.crumbs,.skip,.toast{display:none!important}
  html,body{background:#fff!important;color:#000!important}
  main,.wrap{padding:0!important;margin:0!important;max-width:none!important}
  h1{font-size:14pt;margin:0 0 5pt}
  .cs-sheet{border:0;padding:0;margin:0;background:#fff}
  .cs-head{display:none}
  .cs-grid{display:grid;grid-template-columns:1fr 1fr;gap:7pt 16pt}
  .cs-box h2{font-size:10pt;border-bottom:1.2pt solid #000;color:#000;margin:0 0 4pt}
  .cs-box table,.cs-box ul{font-size:9pt}
  .cs-box.mono li{font-size:8.4pt}
  .cs-box li{margin:1.6pt 0}
  .cs-box{break-inside:avoid}
  .cs-box th,.cs-box td{padding:1.7pt 8pt 1.7pt 0;border-bottom:.4pt solid #bbb;color:#000}
  .cs-box thead th{color:#333}
  .cs-foot{font-size:7pt;color:#444;margin-top:5pt}
  a{color:#000;text-decoration:none}
  @page{size:A4 portrait;margin:12mm}
}