/* 수심달 가이드 공통 스타일 · Pretendard · 브랜드 색(Math Pink #FF6971 · Math Violet #918AFF) */
:root{
  --pink:#FF6971; --pink-soft:#FFEDEE; --pink-deep:#E0505C;
  --violet:#918AFF; --violet-soft:#E7E3FF; --violet-deep:#4B43C9;
  --ink:#2F2F31; --ink-70:#5A5A5E; --ink-50:#85898A; --ink-30:#C3C3C3; --line:#E5E5EA;
  --bg:#F7F7F9; --card:#FFFFFF; --ok:#2E8B57; --ok-soft:#E4F5E6;
  --gold:#8A6500; --gold-soft:#FFF6D6; --warn:#B2600A; --warn-soft:#FFF4E5;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--ink);font-family:"Pretendard Variable",Pretendard,-apple-system,BlinkMacSystemFont,system-ui,Roboto,"Helvetica Neue","Segoe UI","Apple SD Gothic Neo","Noto Sans KR","Malgun Gothic",sans-serif;font-size:16px;line-height:1.65;word-break:keep-all;-webkit-font-smoothing:antialiased}
a{color:var(--pink-deep)}
img{max-width:100%}
.wrap{max-width:960px;margin:0 auto;padding:0 20px 80px}

/* 상단 바 */
header.top{background:var(--card);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
header.top .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 20px}
.brand{font-weight:800;color:var(--pink);text-decoration:none;font-size:15px;white-space:nowrap}
nav.aud{display:flex;gap:4px}
nav.aud a{text-decoration:none;color:var(--ink-70);font-size:13px;font-weight:600;padding:6px 10px;border-radius:999px;white-space:nowrap}
nav.aud a.on,nav.aud a:hover{background:var(--pink-soft);color:var(--pink-deep)}
.crumb{font-size:13px;color:var(--ink-50);margin:18px 0 0}
.crumb a{color:var(--ink-50);text-decoration:none}
.crumb a:hover{color:var(--pink-deep)}

/* 머리 */
.hero{display:flex;gap:24px;align-items:center;padding:24px 0 6px}
.hero img{width:120px;height:120px;object-fit:contain;flex:none}
.eyebrow{display:inline-block;background:var(--pink-soft);color:var(--pink-deep);font-weight:700;font-size:12px;padding:3px 10px;border-radius:999px}
.eyebrow.violet{background:var(--violet-soft);color:var(--violet-deep)}
.eyebrow.good{background:var(--ok-soft);color:var(--ok)}
.hero h1{font-size:30px;line-height:1.3;margin:10px 0 8px;letter-spacing:-0.5px}
.lead{font-size:17px;color:var(--ink-70);margin:0}
.meta{font-size:13px;color:var(--ink-50);margin:6px 0 0}

/* 목차 */
nav.toc{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:16px 20px;margin:22px 0 8px}
nav.toc strong{font-size:14px}
nav.toc ol{margin:6px 0 0;padding-left:20px;columns:2;column-gap:28px}
nav.toc li{margin:4px 0;break-inside:avoid}
nav.toc a{text-decoration:none;color:var(--ink)}
nav.toc a:hover{color:var(--pink-deep)}

/* 챕터 · 페이지 */
section.chapter{margin-top:44px}
.ch-head{margin-bottom:8px}
.ch-num{color:var(--pink-deep);font-weight:800;font-size:13px;letter-spacing:.3px}
.ch-head h2{font-size:24px;margin:4px 0 4px;letter-spacing:-0.3px;border-top:3px solid var(--pink);display:inline-block;padding-top:8px}
.ch-sub{color:var(--ink-70);margin:0}
article.page{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:22px 24px;margin:14px 0;display:grid;grid-template-columns:1fr 1fr;gap:24px;align-items:center}
article.page.text-only,article.page.wide{grid-template-columns:1fr}
.page-text .eyebrow{margin-bottom:6px}
.page-text h3{margin:6px 0 8px;font-size:19px;line-height:1.35}
.page-text p{margin:0 0 8px;color:var(--ink-70)}
.page-text ul{margin:0 0 8px;padding-left:20px;color:var(--ink-70)}
.page-text li{margin:2px 0}
.who{display:flex;align-items:center;gap:8px;margin-bottom:6px}
.who img{width:40px;height:40px;object-fit:contain}
.who span{font-size:12px;color:var(--ink-50);font-weight:600}

/* 그림 */
figure{margin:0}
figure.tablet{background:#1E1E22;border-radius:18px;padding:10px;box-shadow:0 8px 24px rgba(0,0,0,.12)}
figure.tablet img{display:block;width:100%;height:auto;border-radius:10px;background:#fff}
figure.plain img{display:block;width:100%;height:auto;border:1px solid var(--line);border-radius:10px;background:#fff}
figcaption{font-size:12px;color:var(--ink-50);margin-top:6px;text-align:center}
.two{display:grid;grid-template-columns:1fr 1fr;gap:12px}

/* 강조 상자 */
.callout{border-left:5px solid var(--violet);background:var(--violet-soft);border-radius:10px;padding:12px 14px;margin:10px 0 0;font-size:15px;color:var(--ink)}
.callout.warn{border-left-color:var(--pink);background:var(--pink-soft)}
.callout.gold{border-left-color:#E5B300;background:var(--gold-soft)}
.callout.good{border-left-color:var(--ok);background:var(--ok-soft)}
.callout.tip{border-left-color:var(--violet);background:#F4F2FF}
.callout p{margin:4px 0}
.callout ul{margin:4px 0 0;padding-left:20px}

/* 학습 단계 카드 */
.stages{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:10px;margin-top:6px}
.stage{background:#FAFAFC;border:1px solid var(--line);border-radius:12px;overflow:hidden;display:flex;flex-direction:column}
.stage .sh{display:flex;gap:8px;align-items:center;padding:8px 10px;border-bottom:1px solid var(--line);font-weight:700;font-size:13px}
.stage .n{width:22px;height:22px;border-radius:50%;background:var(--pink);color:#fff;font-size:11px;font-weight:800;display:flex;align-items:center;justify-content:center;flex:none}
.stage img{width:100%;height:150px;object-fit:contain;background:#fff;display:block;padding:6px}
.stage .tip{padding:8px 10px;font-size:12px;color:var(--ink-50);line-height:1.45;margin-top:auto}

/* 항목 목록 */
.items{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:8px 0 0;padding:0;list-style:none}
.items li{background:#FAFAFC;border:1px solid var(--line);border-radius:10px;padding:10px 12px;display:flex;gap:10px;align-items:flex-start}
.items .k{width:22px;height:22px;flex:none;border-radius:50%;background:var(--pink-soft);color:var(--pink-deep);font-weight:800;font-size:11px;display:flex;align-items:center;justify-content:center;margin-top:2px}
.items b{display:block;font-size:14px}
.items span{font-size:13px;color:var(--ink-70)}

/* 매티 대화 */
.chat{background:var(--card);border:1px solid var(--line);border-radius:14px;overflow:hidden}
.chat .hd{padding:8px 12px;border-bottom:1px solid var(--line);font-size:12px;font-weight:700;display:flex;gap:6px;align-items:center}
.chat .hd img{width:20px;height:20px;border-radius:50%}
.chat .body{background:#FAFAFC;padding:12px;display:flex;flex-direction:column;gap:8px}
.msg{max-width:84%;padding:8px 12px;border-radius:14px;font-size:13.5px;line-height:1.5;white-space:pre-line}
.msg.student{align-self:flex-end;background:var(--pink);color:#fff;border-bottom-right-radius:4px}
.mattyline{display:flex;gap:6px;align-items:flex-end;max-width:90%}
.mattyline img{width:24px;height:24px;border-radius:50%;flex:none;border:1px solid var(--line);background:#fff}
.mattyline .msg{background:#fff;border:1px solid var(--line);border-bottom-left-radius:4px;max-width:100%}
.chat .in{padding:8px 12px;border-top:1px solid var(--line);font-size:12px;color:var(--ink-30)}

/* 공용 */
.card{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:22px 24px;margin:14px 0}
.card h3{margin:0 0 10px;font-size:18px}
table{width:100%;border-collapse:collapse;background:var(--card);border:1px solid var(--line);border-radius:12px;overflow:hidden;font-size:15px}
th,td{padding:10px 12px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
th{background:#FAFAFC;font-size:14px;color:var(--ink-70);font-weight:700}
tr:last-child td{border-bottom:0}
.table-wrap{overflow-x:auto}
.btn{display:inline-flex;align-items:center;gap:8px;background:var(--pink);color:#fff;text-decoration:none;font-weight:700;padding:12px 20px;border-radius:10px;border:0;cursor:pointer;font-size:15px}
.btn:hover{background:var(--pink-deep)}
.btn.ghost{background:#fff;color:var(--pink-deep);border:1px solid var(--pink)}
.btn.ghost:hover{background:var(--pink-soft)}
.btn.violet{background:var(--violet)}
.pager{display:flex;justify-content:space-between;gap:12px;margin-top:30px}
.pager a{flex:1;background:var(--card);border:1px solid var(--line);border-radius:12px;padding:14px 16px;text-decoration:none;color:var(--ink);font-weight:600}
.pager a small{display:block;color:var(--ink-50);font-size:12px;font-weight:500}
.pager a.next{text-align:right}
footer.site{margin-top:60px;padding-top:20px;border-top:1px solid var(--line);font-size:13px;color:var(--ink-50)}
footer.site a{color:var(--ink-50)}

/* 허브 메인 */
.aud-head{display:flex;align-items:baseline;gap:12px;margin:40px 0 12px}
.aud-head h2{margin:0;font-size:22px}
.aud-head span{color:var(--ink-50);font-size:14px}
.hubgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:14px}
a.gcard{display:flex;flex-direction:column;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:18px 20px;text-decoration:none;color:inherit;transition:border-color .15s,transform .15s}
a.gcard:hover{border-color:var(--pink);transform:translateY(-2px)}
a.gcard img{width:64px;height:64px;object-fit:contain;margin-bottom:8px}
a.gcard .tag{align-self:flex-start;background:var(--pink-soft);color:var(--pink-deep);font-size:11px;font-weight:700;padding:2px 8px;border-radius:999px;margin-bottom:6px}
a.gcard .tag.violet{background:var(--violet-soft);color:var(--violet-deep)}
a.gcard .tag.good{background:var(--ok-soft);color:var(--ok)}
a.gcard h3{margin:0 0 4px;font-size:17px}
a.gcard p{margin:0;font-size:14px;color:var(--ink-70)}
a.gcard .ext{margin-top:8px;font-size:12px;color:var(--ink-50)}

/* 인쇄용 한 장 요약 */
.sheet{background:#fff;border:1px solid var(--line);border-radius:12px;padding:28px 32px;margin:16px 0}
.sheet h2{margin:0 0 4px;font-size:20px}
.sheet .sec{margin-top:18px}
.sheet .sec h3{font-size:14px;margin:0 0 8px;color:var(--pink-deep)}
.flowrow{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}
.flowbox{border:1px solid var(--line);border-radius:10px;padding:10px 12px;background:#FAFAFC;font-size:13px}
.flowbox b{display:block;font-size:14px;margin-bottom:2px}
.flowbox .gate{display:block;margin-top:6px;color:var(--pink-deep);font-weight:700;font-size:12px}
.flowbox.accent{border-color:var(--pink);background:var(--pink-soft)}
.modes{display:grid;grid-template-columns:repeat(5,1fr);gap:8px}
.mode{border:1px solid var(--line);border-radius:10px;padding:10px 8px;text-align:center;font-size:12px;background:#fff}
.mode b{display:block;font-size:14px;margin:4px 0 2px}
.mode .n{display:inline-flex;width:22px;height:22px;border-radius:50%;background:var(--pink);color:#fff;font-weight:800;font-size:11px;align-items:center;justify-content:center}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}
.grid2{display:grid;grid-template-columns:repeat(2,1fr);gap:8px}
.mini{border:1px solid var(--line);border-radius:10px;padding:10px 12px;font-size:13px;background:#fff}
.mini b{display:block;font-size:14px;margin-bottom:2px}
.dot{display:inline-block;width:10px;height:10px;border-radius:50%;margin-right:6px;vertical-align:middle}
@media print{header.top,.crumb,.no-print,footer.site,.pager{display:none!important}body{background:#fff}.sheet{border:0;page-break-after:always;margin:0;padding:12mm 14mm}.sheet:last-child{page-break-after:auto}.wrap{padding:0;max-width:none}}

@media (max-width:760px){
  article.page{grid-template-columns:1fr}
  .two{grid-template-columns:1fr}
  nav.toc ol{columns:1}
  .hero{flex-direction:column;align-items:flex-start;gap:12px}
  .hero img{width:88px;height:88px}
  .hero h1{font-size:25px}
  .items{grid-template-columns:1fr}
  .pager{flex-direction:column}
  .flowrow,.modes,.grid3{grid-template-columns:1fr 1fr}
  header.top .wrap{flex-wrap:wrap}
}