/* ============================================================
   바꿈수학 이야기 — 디자인 시스템
   동봉된 디자인 시안(바꿈수학-사이트-디자인.html)에서 추출.
   색·폰트·컴포넌트는 이 파일 한 곳에서 관리합니다.
   ============================================================ */
:root{
  --white:#FFFFFF;
  --mist:#F2F9FB;        /* 바다 안개 - 연한 섹션 배경 */
  --foam:#DDF0F4;        /* 물거품 - 배지/칩 배경 */
  --whale:#137A92;       /* 고래색 - 로고 원색, 주인공 */
  --whale-soft:#3D97AC;  /* 옅은 고래색 - hover */
  --deep:#0C4E5E;        /* 깊은 바다 - 제목/짙은 면 */
  --ink:#233840;         /* 본문 */
  --muted:#5E7680;       /* 보조 텍스트 */
  --line:#D8EAEF;        /* 경계선 */
  --radius:14px;
  --maxw:1080px;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'Pretendard',-apple-system,BlinkMacSystemFont,'Apple SD Gothic Neo','Malgun Gothic',sans-serif;
  background:var(--white);
  color:var(--ink);
  line-height:1.7;
  -webkit-font-smoothing:antialiased;
}
.serif{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif}
a{color:inherit;text-decoration:none}

/* 프로 디테일: 선택 색·키보드 포커스·버튼 눌림·모션 존중 */
::selection{background:var(--foam);color:var(--deep)}
:focus-visible{outline:2.5px solid var(--whale);outline-offset:2px;border-radius:4px}
a:focus:not(:focus-visible),button:focus:not(:focus-visible),summary:focus:not(:focus-visible){outline:none}
.btn:active{transform:translateY(0) scale(.98)}
@media(prefers-reduced-motion:reduce){*{animation-duration:.001ms!important;transition-duration:.001ms!important}}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 24px}

/* Header */
header{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.88);
  backdrop-filter:saturate(140%) blur(10px);
  border-bottom:1px solid var(--line);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:82px}
.logo{display:flex;align-items:center;gap:11px;cursor:pointer}
.logo img{height:42px;width:auto}
.logo-text{font-weight:800;font-size:19px;color:var(--deep);letter-spacing:-.4px}
.logo-text small{display:block;font-size:11px;font-weight:500;color:var(--muted);letter-spacing:.5px}
.menu{display:flex;align-items:center;gap:30px}
.menu a{font-size:15px;font-weight:500;color:var(--ink);cursor:pointer;transition:color .15s}
.menu a:hover{color:var(--whale)}
.menu a.btn,.menu a.btn:hover{color:#fff}
.btn{
  display:inline-flex;align-items:center;gap:7px;
  background:var(--whale);color:#fff;
  padding:11px 20px;border-radius:100px;
  font-size:14px;font-weight:600;cursor:pointer;border:none;
  transition:transform .15s, background .15s;
}
.btn:hover{background:var(--deep);transform:translateY(-1px)}
.btn-ghost{background:transparent;color:var(--whale);border:1.5px solid var(--line)}
.btn-ghost:hover{background:var(--mist);color:var(--deep);transform:none}
.menu-toggle{display:none;background:none;border:none;cursor:pointer;padding:6px}

/* Hero */
.hero{position:relative;overflow:hidden;background:var(--white)}
.hero-inner{position:relative;z-index:2;padding:96px 24px 84px}
.hero-copy{max-width:500px}
.eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-size:13px;font-weight:600;color:var(--whale);
  letter-spacing:.4px;margin-bottom:22px;
  background:var(--foam);padding:7px 14px;border-radius:100px;
}
.eyebrow .dot{width:6px;height:6px;border-radius:50%;background:var(--whale)}
.hero h1{
  font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;
  font-size:clamp(32px,5vw,52px);
  font-weight:800;line-height:1.28;color:var(--deep);
  letter-spacing:-1.6px;margin-bottom:24px;word-break:keep-all;
}
.hero h1 em{font-style:normal;color:var(--whale);position:relative;white-space:nowrap}
.hero h1 em svg{position:absolute;left:0;bottom:-8px;width:100%;height:9px}
.hero p.lead{
  font-size:clamp(16px,2vw,18.5px);color:var(--ink);
  max-width:540px;margin-bottom:36px;line-height:1.8;
}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap}
/* 우측 이미지 — 화면 오른쪽 끝까지 꽉 채우고 사선으로 콘텐츠와 이어짐.
   /hero.png 가 없으면 옅은 고래 로고로 자동 대체 */
/* 우측 이미지 — 그림 전체가 잘리지 않게 contain 으로 담고, 왼쪽 가장자리를
   부드럽게 페이드해 헤드라인 영역과 자연스럽게 이어진다. 그림 배경이 흰 종이라
   위아래 여백은 사이트 흰 배경과 이음새 없이 섞인다. */
.hero-media{
  position:absolute;top:-8px;bottom:-8px;z-index:0;
  /* 가운데 콘텐츠 컬럼 기준으로 넓게 잡아 그림이 크게, 히어로 높이를 꽉 채운다 */
  left:36%;
  right:max(0px, calc((100% - 1240px) / 2));
  background-image:url('/hero.png'),url('/whale.png');
  background-repeat:no-repeat,no-repeat;
  background-position:center,center;
  background-size:contain,24%;
  background-color:transparent;
  /* 사방 가장자리를 부드럽게 녹여 사각 이미지 느낌 없이 자연스럽게 퍼지게.
     왼쪽(텍스트 쪽)은 더 강하게 비워 글씨가 잘 읽히게 한다. */
  -webkit-mask-image:
    linear-gradient(to right, transparent 0%, rgba(0,0,0,.35) 24%, #000 50%, #000 92%, transparent 100%),
    linear-gradient(to bottom, transparent 0%, rgba(0,0,0,.4) 16%, #000 30%, #000 72%, rgba(0,0,0,.4) 86%, transparent 100%);
  mask-image:
    linear-gradient(to right, transparent 0%, rgba(0,0,0,.35) 24%, #000 50%, #000 92%, transparent 100%),
    linear-gradient(to bottom, transparent 0%, rgba(0,0,0,.4) 16%, #000 30%, #000 72%, rgba(0,0,0,.4) 86%, transparent 100%);
  -webkit-mask-composite:source-in;
  mask-composite:intersect;
}

/* 고백 클래스 영어 표기 */
.feat-en{font-size:.78em;font-weight:600;opacity:.72;letter-spacing:.2px}

/* 물결 구분선 - 시그니처 (은은하게) */
.wave-divider{display:block;width:100%;height:26px;margin-top:-1px;position:relative;z-index:3}

/* Section base */
section.block{padding:64px 0}
.sec-head{display:flex;align-items:flex-end;justify-content:space-between;margin-bottom:34px;gap:20px;flex-wrap:wrap}
.sec-head h2{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:clamp(24px,3vw,31px);font-weight:700;color:var(--deep);letter-spacing:-.5px}
.sec-head p{font-size:15px;color:var(--muted);margin-top:6px}
.sec-link{font-size:14px;font-weight:600;color:var(--whale);cursor:pointer;display:inline-flex;align-items:center;gap:5px}

/* Post list */
.posts{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.post-card{
  background:var(--white);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 26px 24px;cursor:pointer;
  transition:transform .18s, box-shadow .18s, border-color .18s;
  display:flex;flex-direction:column;
}
.post-card:hover{transform:translateY(-3px);box-shadow:0 14px 36px rgba(19,122,146,.12);border-color:var(--whale-soft)}
.pc-top{display:flex;align-items:center;gap:12px;margin-bottom:14px}
.pc-date{
  font-size:12px;font-weight:800;color:var(--whale);
  background:var(--foam);padding:4px 10px;border-radius:7px;letter-spacing:.4px;
}
.pc-cat{font-size:12px;font-weight:600;color:var(--muted)}
.post-card h3{font-size:19px;font-weight:700;color:var(--deep);line-height:1.45;letter-spacing:-.4px;margin-bottom:9px}
.post-card p{font-size:14.5px;color:var(--ink);line-height:1.65;flex:1}
.pc-more{font-size:13px;font-weight:600;color:var(--whale);margin-top:16px;display:inline-flex;align-items:center;gap:5px}

/* Feature (about) - 깊은 바다 */
.about{background:var(--deep);color:#fff;border-radius:24px;padding:52px 44px;margin:8px 0;position:relative;overflow:hidden}
.about::after{
  content:"";position:absolute;right:-30px;bottom:-40px;width:260px;height:260px;
  background:url('/whale.png') center/contain no-repeat;
  opacity:.07;transform:rotate(-8deg);pointer-events:none;
}
.about .eyebrow{background:rgba(255,255,255,.1);color:#A9D8E4}
.about h2{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;color:#fff;font-size:clamp(24px,3vw,31px);font-weight:700;letter-spacing:-.5px;margin-bottom:14px}
.about > .wrap-inner > p{color:#BFDDE6;max-width:600px;margin-bottom:36px;font-size:16px}
.feats{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;position:relative;z-index:1}
.feat{background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.1);border-radius:var(--radius);padding:24px}
.feat .fi{width:40px;height:40px;border-radius:10px;background:var(--whale);display:grid;place-items:center;margin-bottom:16px}
.feat h4{font-size:17px;font-weight:700;margin-bottom:8px}
.feat p{font-size:14px;color:#ACD2DC;line-height:1.6}

/* CTA */
.cta{
  background:var(--mist);
  border:1px solid var(--line);border-radius:24px;
  padding:52px 44px;text-align:center;position:relative;
}
.cta h2{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:clamp(24px,3vw,32px);font-weight:700;color:var(--deep);letter-spacing:-.6px;margin-bottom:14px}
.cta p{font-size:16px;color:var(--ink);margin-bottom:30px}
.cta-actions{display:flex;gap:12px;justify-content:center;flex-wrap:wrap}
.btn-kakao{background:#FEE500;color:#3A2929}
.btn-kakao:hover{background:#F5DC00;color:#3A2929;transform:translateY(-1px)}

/* Footer */
footer{border-top:1px solid var(--line);padding:44px 0 40px;margin-top:20px;background:var(--mist)}
.foot{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap}
.foot .fcol h5{font-size:14px;font-weight:700;color:var(--deep);margin-bottom:12px}
.foot .fcol p,.foot .fcol a{font-size:13.5px;color:var(--muted);line-height:1.9;display:block}
.foot-brand{max-width:290px}
.foot-brand p{margin-top:12px}
.copy{margin-top:32px;padding-top:22px;border-top:1px solid var(--line);font-size:12.5px;color:var(--muted)}

/* Article view */
.article-hero{padding:44px 0 8px}
.back{display:inline-flex;align-items:center;gap:6px;font-size:14px;font-weight:600;color:var(--whale);cursor:pointer;margin-bottom:28px}
.article-meta{display:flex;align-items:center;gap:12px;margin-bottom:18px}
.article h1{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:clamp(27px,4vw,40px);font-weight:700;color:var(--deep);line-height:1.4;letter-spacing:-.8px;margin-bottom:22px;max-width:760px}
.byline{display:flex;align-items:center;gap:12px;padding-bottom:30px;border-bottom:1px solid var(--line);margin-bottom:34px}
.avatar{width:44px;height:44px;border-radius:50%;background:var(--whale);color:#fff;display:grid;place-items:center;font-weight:700;font-size:16px}
.byline .bn{font-size:15px;font-weight:700;color:var(--deep)}
.byline .bd{font-size:13px;color:var(--muted)}
.article-body{max-width:720px;font-size:17px;line-height:1.9;color:var(--ink)}
.article-body p{margin-bottom:22px}
.article-body h2{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:22px;font-weight:700;color:var(--deep);margin:38px 0 16px;letter-spacing:-.3px}
.article-body h3{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:19px;font-weight:700;color:var(--deep);margin:28px 0 12px}
.article-body ul,.article-body ol{margin:0 0 22px 22px}
.article-body li{margin-bottom:8px}
.article-body strong{color:var(--deep)}
.article-body blockquote{
  border-left:3px solid var(--whale);padding:14px 0 14px 20px;margin:26px 0;
  color:var(--deep);font-size:17px;background:var(--mist);border-radius:0 10px 10px 0;
}
.article-foot{
  max-width:720px;margin-top:44px;padding:28px;border-radius:var(--radius);
  background:var(--mist);border:1px solid var(--line);
  display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;
}
.article-foot .af-t strong{display:block;color:var(--deep);font-size:16px;margin-bottom:4px}
.article-foot .af-t span{font-size:13.5px;color:var(--muted)}

/* 목록 페이지 헤더 / 페이지네이션 */
.page-head{padding:52px 0 8px}
.page-head h1{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:clamp(28px,4vw,40px);font-weight:700;color:var(--deep);letter-spacing:-.6px;margin-bottom:10px}
.page-head p{color:var(--muted);font-size:15.5px}
.pager{display:flex;justify-content:center;align-items:center;gap:8px;margin-top:44px}
.pager a,.pager span{
  min-width:40px;height:40px;padding:0 12px;border-radius:10px;border:1px solid var(--line);
  display:inline-flex;align-items:center;justify-content:center;font-size:14px;font-weight:600;color:var(--ink);
}
.pager a:hover{border-color:var(--whale-soft);color:var(--whale)}
.pager .cur{background:var(--whale);color:#fff;border-color:var(--whale)}
.pager .disabled{opacity:.4;pointer-events:none}

/* 빈 상태 */
.empty{text-align:center;padding:70px 20px;color:var(--muted)}
.empty h3{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;color:var(--deep);font-size:20px;margin-bottom:8px}

/* ============================================================
   관리자 화면 (/admin)
   ============================================================ */
.admin-topbar{background:var(--deep);color:#fff}
.admin-topbar .nav{height:64px}
.admin-topbar .logo-text{color:#fff}
.admin-topbar .logo-text small{color:#A9D8E4}
.admin-topbar a{color:#BFDDE6;font-size:14px;font-weight:600}
.admin-wrap{max-width:960px;margin:0 auto;padding:36px 24px 80px}
.admin-h1{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:26px;color:var(--deep);margin-bottom:6px}
.admin-sub{color:var(--muted);font-size:14.5px;margin-bottom:28px}

.flash{padding:13px 18px;border-radius:12px;margin-bottom:22px;font-size:14.5px;font-weight:600}
.flash.ok{background:#E4F5EA;color:#1E7A44;border:1px solid #BFE6CD}
.flash.warn{background:#FFF4E0;color:#9A6B00;border:1px solid #F3DFB0}
.flash.info{background:var(--foam);color:var(--deep);border:1px solid var(--line)}

.admin-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px 24px;margin-bottom:18px}
.admin-card.pending{border-color:var(--whale-soft);box-shadow:0 8px 26px rgba(19,122,146,.08)}
.admin-section-title{font-size:15px;font-weight:800;color:var(--deep);letter-spacing:.2px;margin:34px 0 14px;display:flex;align-items:center;gap:8px}
.count-pill{background:var(--whale);color:#fff;font-size:12px;font-weight:700;border-radius:100px;padding:2px 10px}

.draft-top{display:flex;align-items:center;gap:10px;margin-bottom:8px;flex-wrap:wrap}
.draft-title{font-size:18px;font-weight:700;color:var(--deep);line-height:1.4}
.draft-summary{font-size:14px;color:var(--muted);margin-bottom:14px}
.draft-actions{display:flex;gap:8px;flex-wrap:wrap}
.btn-sm{padding:8px 15px;font-size:13px;border-radius:9px}
.btn-danger{background:#fff;color:#C0392B;border:1.5px solid #F0C4BE}
.btn-danger:hover{background:#FBEAE8;color:#C0392B;transform:none}
.btn-line{background:#fff;color:var(--whale);border:1.5px solid var(--line)}
.btn-line:hover{background:var(--mist);transform:none}

.tag{font-size:11.5px;font-weight:700;padding:3px 9px;border-radius:6px;letter-spacing:.3px}
.tag.draft{background:#FFF4E0;color:#9A6B00}
.tag.published{background:#E4F5EA;color:#1E7A44}
.tag.hidden{background:#EEE;color:#777}
.tag.cat{background:var(--foam);color:var(--deep)}

/* 자동 발행 스위치 */
.switch-row{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.switch-row .st{font-weight:700;color:var(--deep);font-size:15px}
.switch-row .sd{font-size:13px;color:var(--muted);margin-top:3px}
.switch{position:relative;width:56px;height:30px;flex-shrink:0}
.switch input{opacity:0;width:0;height:0}
.slider{position:absolute;inset:0;background:#CBD9DE;border-radius:100px;transition:.2s;cursor:pointer}
.slider::before{content:"";position:absolute;width:22px;height:22px;left:4px;top:4px;background:#fff;border-radius:50%;transition:.2s}
.switch input:checked + .slider{background:var(--whale)}
.switch input:checked + .slider::before{transform:translateX(26px)}

/* 관리자 표 (발행 글 관리) */
.tbl{width:100%;border-collapse:collapse;font-size:14px}
.tbl th,.tbl td{text-align:left;padding:11px 10px;border-bottom:1px solid var(--line)}
.tbl th{font-size:12.5px;color:var(--muted);font-weight:700}
.tbl td .row-actions{display:flex;gap:6px;flex-wrap:wrap}

/* 로그인 화면 */
.login-wrap{max-width:380px;margin:80px auto;padding:0 24px;text-align:center}
.login-wrap img{height:64px;margin-bottom:20px}
.login-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:32px 28px;text-align:left}
.field{margin-bottom:16px}
.field label{display:block;font-size:13px;font-weight:700;color:var(--deep);margin-bottom:6px}
.field input,.field textarea,.field select{
  width:100%;padding:11px 13px;border:1px solid var(--line);border-radius:10px;
  font-size:14.5px;font-family:inherit;color:var(--ink);background:#fff;
}
.field input:focus,.field textarea:focus{outline:none;border-color:var(--whale-soft)}
.field textarea{min-height:320px;line-height:1.7;resize:vertical}

/* ============================================================
   강의형 개별 글 (Day N/360) — 영어판 구조를 고래·블루로
   ============================================================ */
.lesson-head{
  background:var(--deep);color:#fff;border-radius:20px;
  padding:34px 34px 30px;margin:30px 0 8px;position:relative;overflow:hidden;
}
.lesson-head::after{
  content:"";position:absolute;right:-24px;bottom:-34px;width:200px;height:200px;
  background:url('/whale.png') center/contain no-repeat;opacity:.06;transform:rotate(-8deg);
}
.lesson-badges{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:16px}
.lb{font-size:12px;font-weight:700;border-radius:100px;padding:5px 12px;letter-spacing:.3px}
.lb-day{background:var(--whale);color:#fff}
.lb-region{background:rgba(255,255,255,.12);color:#BFDDE6}
.lb-level{background:var(--foam);color:var(--deep)}
.lesson-head h1{
  font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:clamp(24px,3.6vw,34px);
  font-weight:700;line-height:1.35;letter-spacing:-.6px;margin-bottom:16px;color:#fff;
}
.lesson-byline{display:flex;align-items:center;gap:11px;position:relative;z-index:1}
.lesson-byline .avatar{background:var(--whale)}
.lesson-byline .bn{font-size:14.5px;font-weight:700;color:#fff}
.lesson-byline .bd{font-size:12.5px;color:#9FC7D3}

.lesson-body{max-width:760px;margin:0 auto;padding-top:8px}
.lesson-sec{margin:34px 0}
.lesson-h{
  display:flex;align-items:center;gap:9px;
  font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:20px;font-weight:700;color:var(--deep);
  margin-bottom:16px;letter-spacing:-.3px;
}
.lesson-h .ico{width:26px;height:26px;border-radius:8px;background:var(--foam);display:grid;place-items:center;flex-shrink:0}
.lesson-h .ico svg{width:15px;height:15px}
.lesson-concept p{font-size:16.5px;line-height:1.9;color:var(--ink);margin-bottom:14px}

/* 세로 분수 — [[분자/분모]] 가 교과서처럼 위/아래로 쌓여 표시된다 */
.frac{display:inline-flex;flex-direction:column;align-items:center;justify-content:center;
  vertical-align:-0.42em;line-height:1.12;margin:0 .15em;text-align:center;font-size:.92em}
.frac>.fn{display:block;padding:0 .35em;border-bottom:1.5px solid currentColor}
.frac>.fd{display:block;padding:0 .35em}

/* 공식·패턴 표 */
.table-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:12px}
.lesson-table{width:100%;border-collapse:collapse;font-size:14.5px;min-width:520px}
.lesson-table th,.lesson-table td{text-align:left;padding:12px 14px;border-bottom:1px solid var(--line);vertical-align:top}
.lesson-table thead th{background:var(--mist);color:var(--deep);font-weight:700;font-size:13px}
.lesson-table tbody tr:last-child td{border-bottom:none}
.lesson-table .k{font-weight:700;color:var(--whale);white-space:nowrap}
.lesson-table .note{color:var(--muted);font-size:13.5px}

/* 난이도별 예제 */
.ex-group{border:1px solid var(--line);border-left:4px solid var(--whale);border-radius:0 12px 12px 0;padding:16px 18px;margin-bottom:14px;background:var(--white)}
.ex-group.lvl-기초{border-left-color:#3D97AC}
.ex-group.lvl-중급{border-left-color:var(--whale)}
.ex-group.lvl-심화{border-left-color:var(--deep)}
.ex-lvl{font-size:13px;font-weight:800;color:var(--deep);margin-bottom:10px;letter-spacing:.3px}
.ex-item{margin-bottom:12px}
.ex-item:last-child{margin-bottom:0}
.ex-q{font-size:15px;color:var(--ink);line-height:1.7}
.ex-q b{color:var(--whale);font-weight:700;margin-right:4px}
.ex-a{font-size:14.5px;color:var(--muted);line-height:1.7;margin-top:4px;padding-left:14px;border-left:2px solid var(--line)}

/* 시험 핵심 포인트 */
.exam-points{list-style:none;display:grid;gap:9px}
.exam-points li{display:flex;align-items:flex-start;gap:10px;font-size:15px;color:var(--ink);line-height:1.6}
.exam-points .chk{flex-shrink:0;width:20px;height:20px;border-radius:6px;background:var(--foam);display:grid;place-items:center;margin-top:1px}
.exam-points .chk svg{width:12px;height:12px}

/* 이전/다음 강의 */
.lesson-nav{max-width:760px;margin:40px auto 0;display:grid;grid-template-columns:1fr 1fr;gap:12px}
.lnav{border:1px solid var(--line);border-radius:12px;padding:16px 18px;transition:border-color .15s,transform .15s;display:block}
.lnav:hover{border-color:var(--whale-soft);transform:translateY(-2px)}
.lnav .dir{font-size:12px;font-weight:700;color:var(--whale);margin-bottom:5px}
.lnav .t{font-size:14px;font-weight:600;color:var(--deep);line-height:1.4}
.lnav.next{text-align:right}
.lnav.empty{opacity:.35;pointer-events:none}

/* 좁은 화면: 이미지를 위에 가로 배너로 쌓고 아래로 콘텐츠 */
@media(max-width:980px){
  .hero{display:flex;flex-direction:column}
  .hero-media{position:relative;order:-1;left:auto;right:auto;width:100%;height:220px;
    background-position:center 32%;background-size:cover,28%;
    -webkit-mask-image:linear-gradient(to bottom, #000 66%, transparent 100%);
    mask-image:linear-gradient(to bottom, #000 66%, transparent 100%)}
  .hero-inner{padding:22px 24px 58px}
  .hero-copy{max-width:none}
}
@media(max-width:820px){
  .posts{grid-template-columns:1fr}
  .feats{grid-template-columns:1fr}
  .about,.cta{padding:40px 26px}
  .menu a:not(.btn){display:none}
  .menu-toggle{display:block}
  .lesson-nav{grid-template-columns:1fr}
  .lesson-head{padding:26px 22px}
}

/* ============================================================
   수강료 안내 · 수업 시간 · 바꿈에 대하여
   ============================================================ */
/* 수강료 아코디언 */
.acc-wrap{border:1px solid var(--line);border-radius:16px;overflow:hidden;background:var(--white)}
.acc{border-bottom:1px solid var(--line)}
.acc:last-child{border-bottom:none}
.acc summary{
  list-style:none;cursor:pointer;display:flex;align-items:center;justify-content:space-between;
  padding:20px 24px;font-size:17px;font-weight:700;color:var(--deep);
}
.acc summary::-webkit-details-marker{display:none}
.acc summary .sign{position:relative;width:16px;height:16px;flex-shrink:0}
.acc summary .sign::before,.acc summary .sign::after{content:"";position:absolute;background:var(--whale);border-radius:2px}
.acc summary .sign::before{left:0;top:7px;width:16px;height:2px}
.acc summary .sign::after{left:7px;top:0;width:2px;height:16px;transition:opacity .15s}
.acc[open] summary .sign::after{opacity:0}
.acc[open] summary{color:var(--whale)}
.acc-body{padding:2px 24px 18px}
.pr-row{display:flex;align-items:center;justify-content:space-between;padding:12px 0;border-bottom:1px dashed var(--line);font-size:15px}
.pr-row:last-child{border-bottom:none}
.pr-name{color:var(--ink)}
.pr-price{color:var(--deep);font-weight:700;letter-spacing:-.2px}

/* 수업 시간 (30분 블록제) */
.tt-card{background:var(--mist);border:1px solid var(--line);border-radius:20px;padding:34px 30px;position:relative;overflow:hidden}
.tt-card::after{content:"";position:absolute;right:-30px;bottom:-40px;width:220px;height:220px;background:url('/whale.png') center/contain no-repeat;opacity:.05}
.tt-head{font-family:'Pretendard',-apple-system,'Apple SD Gothic Neo',sans-serif;font-size:clamp(24px,3.4vw,32px);font-weight:700;color:var(--deep);letter-spacing:-.6px;margin:6px 0 10px;line-height:1.35}
.tt-lead{color:var(--muted);font-size:15.5px;margin-bottom:26px}
.tt-list{position:relative;z-index:1}
.tt-row{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:18px 0;border-top:1px solid var(--line);flex-wrap:wrap}
.tt-row:first-child{border-top:none}
.tt-t{font-size:17px;font-weight:700;color:var(--deep)}
.tt-m{font-size:13px;color:var(--whale);font-weight:600;margin-top:3px}
.tt-blocks{display:flex;gap:6px;flex-wrap:wrap;justify-content:flex-end;max-width:60%}
.blk{width:20px;height:20px;border-radius:6px;background:var(--whale)}
.tt-note{margin-top:16px;font-size:13.5px;color:var(--muted);text-align:center}

/* 바꿈에 대하여 - 밝은 배경용 특징 카드 */
.feats-light .feat{background:var(--mist);border:1px solid var(--line)}
.feats-light .feat h4{color:var(--deep)}
.feats-light .feat p{color:var(--ink)}
/* 홈 소개 섹션(어두운 배경)의 더 알아보기 링크 */
.about-more{display:inline-flex;align-items:center;gap:6px;margin-top:22px;font-size:14px;font-weight:700;color:#A9D8E4;position:relative;z-index:1}
.about-more svg{color:#A9D8E4}
.about-more:hover{color:#fff}

/* Follow & Archive */
.follow-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.follow-card{border:1px solid var(--line);border-radius:16px;padding:26px 26px 22px;transition:transform .18s,box-shadow .18s,border-color .18s;background:var(--white);display:block}
.follow-card:hover{transform:translateY(-3px);box-shadow:0 14px 36px rgba(19,122,146,.12);border-color:var(--whale-soft)}
.fc-tag{font-size:11.5px;font-weight:800;letter-spacing:1.5px;color:var(--whale);margin-bottom:12px}
.fc-t{font-size:19px;font-weight:700;color:var(--deep);margin-bottom:8px}
.fc-d{font-size:14.5px;color:var(--muted);line-height:1.65;margin-bottom:16px}
.fc-go{font-size:13.5px;font-weight:700;color:var(--whale);display:inline-flex;align-items:center;gap:5px}

/* 대표 블로그 글 목록 */
.blog-list{list-style:none;margin-top:16px;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:var(--white)}
.blog-list li{border-bottom:1px solid var(--line)}
.blog-list li:last-child{border-bottom:none}
.blog-list a{display:flex;align-items:center;gap:12px;padding:15px 20px;transition:background .15s}
.blog-list a:hover{background:var(--mist)}
.bl-tag{flex-shrink:0;font-size:11px;font-weight:800;color:var(--whale);background:var(--foam);border-radius:6px;padding:3px 9px}
.bl-t{flex:1;font-size:14.5px;font-weight:600;color:var(--deep);line-height:1.4}
.bl-date{flex-shrink:0;font-size:12.5px;color:var(--muted);font-variant-numeric:tabular-nums}
.blog-list a svg{flex-shrink:0;color:var(--whale)}
.blog-more{margin-top:10px}
.blog-more summary{list-style:none;cursor:pointer;text-align:center;font-size:13.5px;font-weight:700;color:var(--whale);padding:12px;border:1px solid var(--line);border-radius:12px;background:var(--white);transition:background .15s}
.blog-more summary:hover{background:var(--mist)}
.blog-more summary::-webkit-details-marker{display:none}
.blog-more[open] summary{margin-bottom:10px}
.bl-all{text-align:center;margin-top:16px}
.bl-all a{display:inline-flex;align-items:center;gap:6px;font-size:13.5px;font-weight:700;color:var(--whale)}
.bl-all a svg{color:var(--whale)}

/* Good Morning MATH 제목 + 해 아이콘 */
.gm-title{display:inline-flex;align-items:center;gap:.4em}
.gm-sun{width:.82em;height:.82em;flex-shrink:0;filter:drop-shadow(0 1px 3px rgba(245,158,11,.35))}

/* 영어 슬로건 */
.eng-tagline{display:inline-block;font-size:13px;font-weight:700;letter-spacing:1.5px;color:var(--whale);font-style:italic;margin-bottom:12px}

/* 학원 둘러보기 사진 갤러리 */
.photo-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.photo-card{margin:0;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:var(--mist)}
/* 사진이 없으면(404) 옅은 고래 워터마크가 자리 대신 보임 */
.photo-card .photo-img{display:block;width:100%;aspect-ratio:4/3;background-color:var(--foam);background-repeat:no-repeat,no-repeat;background-position:center,center;background-size:cover,42%}
.photo-card figcaption{padding:12px 15px;font-size:13.5px;color:var(--muted);line-height:1.5}

@media(max-width:820px){
  .follow-grid{grid-template-columns:1fr}
  .tt-blocks{max-width:100%;justify-content:flex-start}
  .photo-grid{grid-template-columns:1fr}
}