@import url('https://fonts.googleapis.com/css2?family=Gowun+Batang:wght@400;700&family=EB+Garamond:ital,wght@0,500;0,600;1,500;1,600&display=swap');
/* === sgbook — SEO GEO 북 (2026-10-10 신설) ===
   은유: 교과서. 짙은 녹색 클로스 표지 + 금박 + 미색 본문 종이.
   분류=장(章), 글=단원, 본문 h2=절 번호. 장치: 책등·차례 점선 지시선·학습 목표 상자·각주·쪽 번호·책갈피 끈·판권면.
   모든 규칙은 .skin-sgbook 범위 안에 둔다. */
.skin-sgbook {
    --sgb-cover: #1F4A3A;
    --sgb-cover-2: #2E6B53;
    --sgb-deep: #13301F;
    --sgb-gold: #B8862B;
    --sgb-gold-lt: #E2B85A;
    --sgb-foil: #EBD08E;
    --sgb-paper: #F8F4EA;
    --sgb-page: #FFFDF7;
    --sgb-ink: #1C2620;
    --sgb-text: #36423A;
    --sgb-muted: #6B7268;
    --sgb-line: #E2DAC4;
    --sgb-sage: #EAF0E8;
    --sgb-marker: rgba(242, 212, 107, .62);
    --sgb-serif: 'Gowun Batang', 'Noto Serif KR', serif;
    --sgb-num: 'EB Garamond', 'Gowun Batang', serif;
    background: var(--sgb-paper); color: var(--sgb-text); overflow-x: clip;
}
.skin-sgbook *, .skin-sgbook *::before, .skin-sgbook *::after { box-sizing: border-box; }
.skin-sgbook a { color: inherit; text-decoration: none; }
.skin-sgbook h1, .skin-sgbook h2, .skin-sgbook h3, .skin-sgbook h4 { font-family: var(--sgb-serif); color: var(--sgb-ink); letter-spacing: -0.01em; }
.skin-sgbook svg { flex-shrink: 0; }
.skin-sgbook mark { background: linear-gradient(transparent 58%, var(--sgb-marker) 58%); color: inherit; padding: 0 .08em; }

/* ── 머리글: 쪽 상단의 이중 괘선 ── */
.skin-sgbook .main-header {
    background: rgba(248, 244, 234, .97); backdrop-filter: blur(6px);
    border-bottom: 0; box-shadow: none; padding: 0; margin: 0;
}
.skin-sgbook .main-header::after {
    content: ''; display: block; height: 6px;
    border-top: 1px solid var(--sgb-cover); border-bottom: 3px solid var(--sgb-cover);
    max-width: 1160px; margin: 0 auto; width: calc(100% - 40px);
}
.skin-sgbook .main-header .containerHeader {
    flex-direction: row; justify-content: space-between; align-items: center; text-align: left;
    max-width: 1200px; min-height: 74px; gap: 24px;
}
.skin-sgbook .main-header .brand-logo,
.skin-sgbook .main-header .brand-logo a {
    font-family: var(--sgb-serif) !important; font-size: 1.5rem; margin: 0; letter-spacing: -0.02em; font-weight: 700;
}
.skin-sgbook .main-header .brand-logo a { display: inline-flex; align-items: center; gap: 11px; color: var(--sgb-cover); }
.skin-sgbook .main-header .brand-logo a::before {
    content: ''; width: 36px; height: 36px; flex: 0 0 36px;
    background: url(/assets/skins/sgbook/mark.svg) center/contain no-repeat;
}
.skin-sgbook .main-header nav { width: auto; border-top: 0; padding-top: 0; }
.skin-sgbook .main-header nav > ul { justify-content: flex-end; gap: 2px; flex-wrap: nowrap; counter-reset: sgbch; }
.skin-sgbook .main-header nav ul li { margin: 0; }
.skin-sgbook .main-header nav ul li a {
    color: var(--sgb-text); font-weight: 600; font-size: .93rem; text-transform: none; font-family: var(--sgb-serif);
    padding: 9px 13px; border-radius: 6px 6px 0 0; border-bottom: 2px solid transparent; transition: background .2s, border-color .2s;
}
.skin-sgbook .main-header nav > ul > li:not(:first-child):not(.has-dropdown) { counter-increment: sgbch; }
.skin-sgbook .main-header nav > ul > li:not(:first-child):not(.has-dropdown) > a::before {
    content: counter(sgbch) '장'; font: 600 .78rem/1 var(--sgb-num); color: var(--sgb-gold); margin-right: 7px;
    padding: 3px 6px; border: 1px solid var(--sgb-gold-lt); border-radius: 3px;
}
.skin-sgbook .main-header nav ul li a:hover { background: var(--sgb-page); border-bottom-color: var(--sgb-gold); color: var(--sgb-cover); }
.skin-sgbook .main-header .dropdown { background: var(--sgb-page); border: 1px solid var(--sgb-line); border-radius: 6px; }
.skin-sgbook .main-header .menu-toggle {
    background: var(--sgb-cover); color: var(--sgb-foil); border-radius: 6px; min-height: 42px; padding: 0 16px;
    font: 700 .95rem/1 var(--sgb-serif); letter-spacing: .08em; box-shadow: inset 0 0 0 1px rgba(235, 208, 142, .5), inset 0 0 0 3px var(--sgb-cover), inset 0 0 0 4px rgba(235, 208, 142, .35);
}

/* 모바일 메뉴 = 차례 쪽 */
.skin-sgbook .mobile-menu-overlay { background: var(--sgb-page); padding: 96px 24px 32px; counter-reset: sgbmch; }
.skin-sgbook .mobile-menu-overlay::before {
    content: '차례'; display: block; font: 700 1.9rem/1.2 var(--sgb-serif); color: var(--sgb-ink);
    padding-bottom: 14px; margin-bottom: 8px; border-bottom: 3px double var(--sgb-cover);
}
.skin-sgbook .mobile-menu-header { background: var(--sgb-cover); border-bottom: 0; padding: 14px 18px; }
.skin-sgbook .mobile-menu-header .logo { color: var(--sgb-foil); font: 700 1.2rem/1.2 var(--sgb-serif); }
.skin-sgbook .close-menu { background: transparent; color: var(--sgb-foil); border: 1px solid rgba(235, 208, 142, .6); min-height: 40px; border-radius: 6px; font-family: var(--sgb-serif); }
.skin-sgbook .mobile-menu-overlay a {
    color: var(--sgb-ink); min-height: 54px; display: flex; align-items: center; gap: 12px; font-family: var(--sgb-serif); font-size: 1.08rem;
    border-bottom: 1px dotted #BFB497; word-break: keep-all;
}
.skin-sgbook .mobile-menu-overlay a:not(:first-of-type) { counter-increment: sgbmch; }
.skin-sgbook .mobile-menu-overlay a:not(:first-of-type)::before {
    content: counter(sgbmch); flex: 0 0 32px; height: 32px; display: grid; place-items: center; border-radius: 4px;
    background: var(--sgb-cover); color: var(--sgb-foil); font: 600 1rem/1 var(--sgb-num);
}
.skin-sgbook .mobile-menu-overlay a:first-of-type::before {
    content: ''; flex: 0 0 32px; height: 32px; border-radius: 4px; background: url(/assets/skins/sgbook/mark.svg) center/contain no-repeat;
}

/* ── 공통 ── */
.skin-sgbook main.container { max-width: 1200px; }
.skin-sgbook .sgb-btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 50px; padding: 0 22px; white-space: nowrap;
    border-radius: 4px; font: 700 1rem/1.2 var(--sgb-serif); transition: transform .2s, background .2s;
}
.skin-sgbook .sgb-btn-solid { background: var(--sgb-cover); color: #FBF3DF; }
.skin-sgbook .sgb-btn-solid:hover { background: var(--sgb-deep); transform: translateY(-1px); }
.skin-sgbook .sgb-btn-line { border: 1.5px solid var(--sgb-cover); color: var(--sgb-cover); background: transparent; }
.skin-sgbook .sgb-btn-line:hover { background: var(--sgb-sage); }
.skin-sgbook .sgb-btn-sm { min-height: 44px; padding: 0 16px; font-size: .92rem; }
.skin-sgbook .sgb-meta { display: flex; flex-wrap: wrap; gap: 6px; margin: 0; color: var(--sgb-muted); font-size: .84rem; }

.skin-sgbook .sgb-section { padding: 76px 0 8px; scroll-margin-top: 90px; }
.skin-sgbook .sgb-section-top { padding-top: 44px; }
.skin-sgbook .sgb-sec-head { margin: 0 0 30px; scroll-margin-top: 90px; }
.skin-sgbook .sgb-sec-label { margin: 0 0 6px; font: 600 .82rem/1 var(--sgb-num); letter-spacing: .22em; color: var(--sgb-gold); }
.skin-sgbook .sgb-sec-title {
    margin: 0; font-size: 2.1rem; line-height: 1.25; font-weight: 700; padding-bottom: 14px;
    background: linear-gradient(var(--sgb-cover), var(--sgb-cover)) left bottom / 56px 4px no-repeat,
                linear-gradient(var(--sgb-line), var(--sgb-line)) left bottom 1px / 100% 1px no-repeat;
}
.skin-sgbook .sgb-sec-desc { margin: 12px 0 0; color: var(--sgb-muted); font-size: 1rem; line-height: 1.65; }

.skin-sgbook .sgb-footnote { display: flex; gap: 6px; margin: 0; font-size: .84rem; line-height: 1.6; }
.skin-sgbook .sgb-fn-mark { font: 600 1rem/1.3 var(--sgb-num); }

/* ── 표지(히어로): 클로스 표지 + 금박 이중 테두리 ── */
.skin-sgbook .sgb-hero {
    position: relative; isolation: isolate; display: grid; grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
    gap: 40px; align-items: center; padding: 76px 0 112px; color: #DCE3D8;
}
.skin-sgbook .sgb-hero::before {
    content: ''; position: absolute; z-index: -2; top: 0; bottom: 0; left: calc(50% - 50vw); right: calc(50% - 50vw);
    background:
        repeating-linear-gradient(45deg, rgba(255, 255, 255, .025) 0 2px, transparent 2px 5px),
        repeating-linear-gradient(-45deg, rgba(0, 0, 0, .05) 0 2px, transparent 2px 5px),
        radial-gradient(1000px 500px at 75% 30%, #2A5A47, var(--sgb-cover) 70%);
}
.skin-sgbook .sgb-hero::after {
    content: ''; position: absolute; z-index: -1; top: 22px; bottom: 22px; left: calc(50% - 50vw + 22px); right: calc(50% - 50vw + 22px);
    max-width: none; border: 1px solid rgba(226, 184, 90, .55); outline: 1px solid rgba(226, 184, 90, .3); outline-offset: -7px; pointer-events: none;
}
.skin-sgbook .sgb-edition { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin: 0 0 22px; font: 600 .84rem/1 var(--sgb-num); letter-spacing: .2em; color: var(--sgb-gold-lt); }
.skin-sgbook .sgb-edition span + span { font-family: var(--sgb-serif); letter-spacing: .1em; padding-left: 12px; border-left: 1px solid rgba(226, 184, 90, .6); }
.skin-sgbook .sgb-hero-title {
    margin: 0; color: #FBF3DF; font-size: clamp(2.1rem, 4.2vw, 3.3rem); line-height: 1.32; font-weight: 700; word-break: keep-all;
}
.skin-sgbook .sgb-hero-title mark { background: none; color: #FFF6DA; padding: 0; text-decoration: underline; text-decoration-color: rgba(226, 184, 90, .7); text-decoration-thickness: .2em; text-underline-offset: .12em; text-decoration-skip-ink: none; }
.skin-sgbook .sgb-hero-lead { margin: 22px 0 0; font-size: 1.08rem; line-height: 1.8; color: #CFD9CC; max-width: 34em; word-break: keep-all; }
.skin-sgbook .sgb-hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.skin-sgbook .sgb-hero .sgb-btn-solid { background: var(--sgb-gold-lt); color: var(--sgb-deep); }
.skin-sgbook .sgb-hero .sgb-btn-solid:hover { background: var(--sgb-foil); }
.skin-sgbook .sgb-hero .sgb-btn-line { border-color: rgba(251, 243, 223, .7); color: #FBF3DF; }
.skin-sgbook .sgb-hero .sgb-btn-line:hover { background: rgba(255, 255, 255, .08); }
.skin-sgbook .sgb-hero-facts { list-style: none; display: flex; flex-wrap: wrap; gap: 0; margin: 32px 0 18px; padding: 0; }
.skin-sgbook .sgb-hero-facts li { display: flex; align-items: baseline; gap: 4px; padding: 0 20px; border-left: 1px solid rgba(226, 184, 90, .45); }
.skin-sgbook .sgb-hero-facts li:first-child { padding-left: 0; border-left: 0; }
.skin-sgbook .sgb-hero-facts b { font: 600 1.7rem/1 var(--sgb-num); color: var(--sgb-foil); }
.skin-sgbook .sgb-hero-facts li:last-child b, .skin-sgbook .sgb-hero-facts .sgb-fact-text b { font-family: var(--sgb-serif); font-size: 1.1rem; }
.skin-sgbook .sgb-hero-facts span { font-size: .88rem; color: #BFCBBC; }
.skin-sgbook .sgb-hero .sgb-footnote { color: #AEBBAC; border-top: 1px solid rgba(226, 184, 90, .35); padding-top: 12px; max-width: 30em; }
.skin-sgbook .sgb-hero .sgb-fn-mark { color: var(--sgb-gold-lt); }
.skin-sgbook .sgb-hero-visual { min-width: 0; }
.skin-sgbook .sgb-hero-art { display: block; width: 100%; height: auto; filter: drop-shadow(0 18px 24px rgba(0, 0, 0, .25)); }

/* 학습 목표 상자 — 표지 아래에 걸친다 */
.skin-sgbook .sgb-goals {
    position: relative; margin: -56px auto 0; max-width: 1100px; background: var(--sgb-page);
    border: 1.5px solid var(--sgb-cover); border-radius: 6px; padding: 34px 32px 26px; box-shadow: 0 16px 34px rgba(19, 48, 31, .12);
}
.skin-sgbook .sgb-goals-tag {
    position: absolute; top: -16px; left: 26px; margin: 0; display: inline-flex; align-items: center; gap: 7px;
    background: var(--sgb-cover); color: #FBF3DF; font: 700 .95rem/1 var(--sgb-serif); padding: 8px 14px; border-radius: 4px;
}
.skin-sgbook .sgb-goals ol { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }
.skin-sgbook .sgb-goals li { display: flex; gap: 12px; font-size: .98rem; line-height: 1.65; color: var(--sgb-text); word-break: keep-all; }
.skin-sgbook .sgb-goals li span {
    flex: 0 0 30px; height: 30px; border-radius: 50%; display: grid; place-items: center;
    border: 1.5px solid var(--sgb-gold); color: var(--sgb-gold); font: 600 1rem/1 var(--sgb-num);
}

/* ── 차례 ── */
.skin-sgbook .sgb-toc { list-style: none; margin: 0; padding: 0; display: grid; gap: 18px; }
.skin-sgbook .sgb-toc-ch { background: var(--sgb-page); border: 1px solid var(--sgb-line); border-radius: 6px; overflow: hidden; }
.skin-sgbook .sgb-toc-head { display: flex; align-items: stretch; transition: background .2s; }
.skin-sgbook .sgb-toc-head:hover { background: #FFF9EA; }
.skin-sgbook .sgb-toc-no {
    flex: 0 0 104px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 4px;
    background: var(--sgb-cover); color: var(--sgb-foil); font: 600 2.7rem/1 var(--sgb-num);
    background-image: linear-gradient(90deg, transparent 0 8px, rgba(226, 184, 90, .5) 8px 10px, transparent 10px);
}
.skin-sgbook .sgb-toc-no small { font-size: .62rem; letter-spacing: .2em; color: #C7D2C3; }
.skin-sgbook .sgb-toc-text { flex: 1; min-width: 0; padding: 22px 26px; display: flex; flex-direction: column; gap: 6px; }
.skin-sgbook .sgb-toc-en { font: 600 .75rem/1 var(--sgb-num); letter-spacing: .2em; color: var(--sgb-gold); }
.skin-sgbook .sgb-toc-line { display: flex; align-items: baseline; gap: 12px; min-width: 0; }
.skin-sgbook .sgb-toc-line strong { font: 700 1.4rem/1.35 var(--sgb-serif); color: var(--sgb-ink); word-break: keep-all; min-width: 0; }
.skin-sgbook .sgb-leader { flex: 1 1 30px; min-width: 30px; border-bottom: 2px dotted #B9AE90; transform: translateY(-5px); }
.skin-sgbook .sgb-toc-count { flex: 0 0 auto; font: 600 1rem/1 var(--sgb-serif); color: var(--sgb-cover); }
.skin-sgbook .sgb-toc-desc { color: var(--sgb-muted); font-size: .95rem; line-height: 1.6; word-break: keep-all; }
.skin-sgbook .sgb-toc-secs { list-style: none; margin: 0; padding: 4px 26px 16px 130px; border-top: 1px dashed var(--sgb-line); }
.skin-sgbook .sgb-toc-secs a { display: flex; gap: 14px; align-items: baseline; padding: 10px 0; border-bottom: 1px dotted #D8CFB6; }
.skin-sgbook .sgb-toc-secs li:last-child a { border-bottom: 0; }
.skin-sgbook .sgb-toc-sno { flex: 0 0 38px; font: 600 1rem/1 var(--sgb-num); color: var(--sgb-gold); }
.skin-sgbook .sgb-toc-stitle { min-width: 0; color: var(--sgb-text); font-size: .98rem; line-height: 1.5; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.skin-sgbook .sgb-toc-secs a:hover .sgb-toc-stitle { color: var(--sgb-cover); text-decoration: underline; text-decoration-color: var(--sgb-gold-lt); text-underline-offset: 4px; }

/* ── 새로 실린 단원: 대표 단원(겹친 쪽) ── */
.skin-sgbook .sgb-lead {
    background: var(--sgb-page); border: 1px solid var(--sgb-line); border-radius: 4px;
    box-shadow: 4px 4px 0 #F1EBDA, 4px 4px 0 1px var(--sgb-line), 8px 8px 0 #EAE2CC, 8px 8px 0 1px var(--sgb-line);
    margin: 0 8px 40px 0;
}
.skin-sgbook .sgb-lead-link { display: grid; grid-template-columns: minmax(0, .92fr) minmax(0, 1.08fr); gap: 36px; padding: 30px; }
.skin-sgbook .sgb-fig { margin: 0; }
.skin-sgbook .sgb-fig-frame { position: relative; aspect-ratio: 4 / 3; overflow: hidden; border: 1px solid var(--sgb-line); background: var(--sgb-sage); padding: 0; }
.skin-sgbook .sgb-fig-img { position: absolute; inset: 0; background: center/cover no-repeat; filter: saturate(.55) sepia(.18) contrast(1.02); transition: transform .5s; }
.skin-sgbook .sgb-fig-blank { position: absolute; inset: 0; display: grid; place-items: center; color: var(--sgb-cover); opacity: .5;
    background: repeating-linear-gradient(0deg, transparent 0 23px, rgba(31, 74, 58, .08) 23px 24px); }
.skin-sgbook .sgb-fig figcaption { margin-top: 10px; font-size: .84rem; color: var(--sgb-muted); }
.skin-sgbook .sgb-fig figcaption b { font-family: var(--sgb-serif); color: var(--sgb-cover); margin-right: 6px; }
.skin-sgbook a:hover .sgb-fig-img { transform: scale(1.03); }
.skin-sgbook .sgb-lead-body { min-width: 0; display: flex; flex-direction: column; gap: 14px; }
.skin-sgbook .sgb-lead-ch { margin: 0; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; font: 700 .92rem/1.3 var(--sgb-serif); color: var(--sgb-cover); }
.skin-sgbook .sgb-lead-ch span { font: 600 .72rem/1 var(--sgb-num); letter-spacing: .14em; background: var(--sgb-gold-lt); color: var(--sgb-deep); padding: 5px 8px; border-radius: 3px; }
.skin-sgbook .sgb-lead-title { margin: 0; font-size: 1.85rem; line-height: 1.38; word-break: keep-all; overflow-wrap: anywhere; }
.skin-sgbook .sgb-lead-link:hover .sgb-lead-title { text-decoration: underline; text-decoration-color: var(--sgb-gold-lt); text-underline-offset: 6px; }
.skin-sgbook .sgb-lead-excerpt { margin: 0; line-height: 1.8; color: var(--sgb-text); }
.skin-sgbook .sgb-lead-plan { background: var(--sgb-sage); border-left: 4px solid var(--sgb-cover); padding: 14px 18px; border-radius: 0 4px 4px 0; }
.skin-sgbook .sgb-lead-plan p { margin: 0 0 6px; font: 700 .88rem/1.2 var(--sgb-serif); color: var(--sgb-cover); }
.skin-sgbook .sgb-lead-plan ol { margin: 0; padding-left: 1.3em; font-size: .93rem; line-height: 1.7; color: var(--sgb-text); }
.skin-sgbook .sgb-lead-foot { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 12px; margin-top: auto; padding-top: 12px; border-top: 1px solid var(--sgb-line); }
.skin-sgbook .sgb-more { display: inline-flex; align-items: center; gap: 6px; font: 700 .95rem/1 var(--sgb-serif); color: var(--sgb-cover); }

/* 단원 카드 = 교과서 한 쪽 */
.skin-sgbook .sgb-pages { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 26px; }
.skin-sgbook .sgb-page {
    position: relative; background: var(--sgb-page); border: 1px solid var(--sgb-line); border-radius: 2px 2px 2px 2px;
    transition: transform .2s, box-shadow .2s;
}
.skin-sgbook .sgb-page::after {
    content: ''; position: absolute; top: -1px; right: -1px; width: 22px; height: 22px;
    background: linear-gradient(225deg, var(--sgb-paper) 0 50%, #E9E1CB 50% 100%); box-shadow: -1px 1px 2px rgba(0, 0, 0, .06);
}
.skin-sgbook .sgb-page:hover { transform: translateY(-3px); box-shadow: 0 14px 28px rgba(19, 48, 31, .1); }
.skin-sgbook .sgb-page-link { display: flex; flex-direction: column; height: 100%; padding: 18px 22px 16px; }
.skin-sgbook .sgb-page-run { display: flex; gap: 8px; align-items: baseline; padding: 0 26px 9px 0; border-bottom: 1px solid var(--sgb-line); font-size: .78rem; color: var(--sgb-muted); min-width: 0; }
.skin-sgbook .sgb-page-run span:first-child { font-family: var(--sgb-serif); font-weight: 700; color: var(--sgb-cover); flex: 0 0 auto; }
.skin-sgbook .sgb-page-run-name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; min-width: 0; }
.skin-sgbook .sgb-page-no { margin-top: 16px; font: italic 600 2.2rem/1 var(--sgb-num); color: var(--sgb-gold); }
.skin-sgbook .sgb-page-title { margin: 8px 0 0; font-size: 1.2rem; line-height: 1.45; word-break: keep-all; overflow-wrap: anywhere;
    display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.skin-sgbook .sgb-page-excerpt { margin: 10px 0 18px; color: var(--sgb-muted); font-size: .92rem; line-height: 1.7;
    display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.skin-sgbook .sgb-page-foot { margin-top: auto; display: flex; justify-content: space-between; align-items: center; gap: 10px; padding-top: 10px; border-top: 1px dotted #CFC5A8; }
.skin-sgbook .sgb-folio { font: italic 500 .95rem/1 var(--sgb-num); color: var(--sgb-muted); flex: 0 0 auto; }

/* ── 이 책의 활용법 ── */
.skin-sgbook .sgb-how { position: relative; isolation: isolate; margin-top: 84px; padding: 64px 0; }
.skin-sgbook .sgb-how::before {
    content: ''; position: absolute; z-index: -1; inset: 0 calc(50% - 50vw);
    background: var(--sgb-sage);
    border-top: 1px solid #D3DED0; border-bottom: 1px solid #D3DED0;
}
.skin-sgbook .sgb-how-inner { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.6fr); gap: 44px; align-items: start; }
.skin-sgbook .sgb-how-intro h2 { margin: 0 0 14px; font-size: 2rem; }
.skin-sgbook .sgb-how-intro p:last-child { margin: 0; line-height: 1.75; color: var(--sgb-text); word-break: keep-all; }
.skin-sgbook .sgb-how-steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.skin-sgbook .sgb-how-steps li { position: relative; background: var(--sgb-page); border: 1px solid #D3DED0; border-radius: 4px; padding: 24px 20px 22px; }
.skin-sgbook .sgb-how-no { position: absolute; top: 14px; right: 18px; font: italic 600 2.4rem/1 var(--sgb-num); color: rgba(184, 134, 43, .45); }
.skin-sgbook .sgb-how-icon { width: 44px; height: 44px; border-radius: 4px; display: grid; place-items: center; background: var(--sgb-cover); color: var(--sgb-foil); }
.skin-sgbook .sgb-how-steps h3 { margin: 16px 0 8px; font-size: 1.12rem; line-height: 1.4; word-break: keep-all; }
.skin-sgbook .sgb-how-steps p { margin: 0; color: var(--sgb-muted); font-size: .92rem; line-height: 1.7; word-break: keep-all; }

/* ── 지난 단원: 쌓아 둔 책 ── */
.skin-sgbook .sgb-shelf { list-style: none; margin: 0 auto; padding: 0; max-width: 1000px; display: flex; flex-direction: column; gap: 6px; }
.skin-sgbook .sgb-spine { --c: var(--sgb-cover); border-radius: 3px; background: var(--c); box-shadow: inset 0 3px 0 rgba(255, 255, 255, .08), inset 0 -3px 0 rgba(0, 0, 0, .18), 0 2px 0 rgba(0, 0, 0, .08); transition: transform .2s; }
.skin-sgbook .sgb-spine:hover { transform: translateX(8px); }
.skin-sgbook .sgb-spine-1 { --c: #6E5129; margin: 0 2% 0 3%; }
.skin-sgbook .sgb-spine-2 { --c: #2F4458; margin: 0 4% 0 0; }
.skin-sgbook .sgb-spine-3 { --c: #8A3D2C; margin: 0 1% 0 5%; }
.skin-sgbook .sgb-spine a {
    position: relative; display: flex; align-items: center; gap: 16px; padding: 10px 22px 10px 26px; color: #F6EBCF; min-height: 48px;
    background:
        linear-gradient(90deg, transparent 0 10px, rgba(226, 184, 90, .75) 10px 13px, transparent 13px 17px, rgba(226, 184, 90, .75) 17px 18px, transparent 18px),
        linear-gradient(270deg, transparent 0 10px, rgba(226, 184, 90, .75) 10px 13px, transparent 13px);
}
.skin-sgbook .sgb-spine-no { flex: 0 0 auto; padding-left: 8px; font: italic 600 1.15rem/1 var(--sgb-num); color: var(--sgb-gold-lt); }
.skin-sgbook .sgb-spine-title { flex: 1; min-width: 0; font: 700 .98rem/1.45 var(--sgb-serif); word-break: keep-all; overflow-wrap: anywhere;
    display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.skin-sgbook .sgb-spine-ch { flex: 0 0 auto; margin-right: 10px; font: 700 .78rem/1 var(--sgb-serif); padding: 5px 8px; border: 1px solid rgba(226, 184, 90, .6); border-radius: 3px; color: var(--sgb-foil); }

/* ── 빈 책 (글 0편) ── */
.skin-sgbook .sgb-blank {
    display: flex; align-items: center; gap: 30px; padding: 34px; background: var(--sgb-page);
    border: 1.5px dashed #C9BE9F; border-radius: 6px;
}
.skin-sgbook .sgb-blank-art { flex: 0 0 220px; width: 220px; height: auto; }
.skin-sgbook .sgb-blank-copy h3 { margin: 0 0 10px; font-size: 1.45rem; line-height: 1.4; word-break: keep-all; }
.skin-sgbook .sgb-blank-copy p { margin: 0 0 16px; line-height: 1.75; color: var(--sgb-muted); word-break: keep-all; }
.skin-sgbook .sgb-blank-copy p:last-child { margin-bottom: 0; }

/* ── 판권면 + 바닥글 ── */
.skin-sgbook .sgb-colophon { position: relative; isolation: isolate; margin-top: 96px; padding: 56px 0 40px; color: #C9D3C6; }
.skin-sgbook .sgb-colophon::before { content: ''; position: absolute; z-index: -1; inset: 0 calc(50% - 50vw); background: var(--sgb-deep); }
.skin-sgbook .sgb-colophon-inner { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 2fr); gap: 44px; padding: 30px; border: 1px solid rgba(226, 184, 90, .35); }
.skin-sgbook .sgb-colophon-title { display: flex; gap: 14px; align-items: center; }
.skin-sgbook .sgb-colophon-mark { flex: 0 0 48px; height: 48px; background: url(/assets/skins/sgbook/mark.svg) center/contain no-repeat; }
.skin-sgbook .sgb-colophon-title strong { display: block; font: 700 1.35rem/1.3 var(--sgb-serif); color: #FBF3DF; }
.skin-sgbook .sgb-colophon-title span { font: 600 .78rem/1 var(--sgb-num); letter-spacing: .22em; color: var(--sgb-gold-lt); }
.skin-sgbook .sgb-colophon-dl { margin: 0; display: grid; grid-template-columns: 5.5em minmax(0, 1fr); gap: 12px 18px; font-size: .9rem; line-height: 1.7; }
.skin-sgbook .sgb-colophon-dl dt { font: 700 .88rem/1.7 var(--sgb-serif); color: var(--sgb-gold-lt); border-right: 1px solid rgba(226, 184, 90, .35); }
.skin-sgbook .sgb-colophon-dl dd { margin: 0; word-break: keep-all; }
.skin-sgbook .sgb-colophon-chs { display: flex; flex-wrap: wrap; gap: 6px 18px; }
.skin-sgbook .sgb-colophon-chs a { color: #EDE6CF; border-bottom: 1px solid rgba(226, 184, 90, .4); }
.skin-sgbook .sgb-colophon-chs a:hover { color: #fff; }
.skin-sgbook footer { background: var(--sgb-deep); color: rgba(220, 227, 216, .55); margin-top: 0; padding: 0 0 34px; text-align: left; font-size: .8rem; }
.skin-sgbook footer .container { max-width: 1200px; }
.skin-sgbook footer p { margin: 0; padding-top: 18px; border-top: 1px solid rgba(255, 255, 255, .1); }

/* ── 쪽 매김 ── */
.skin-sgbook .pagination { background: var(--sgb-page) !important; border: 1px solid var(--sgb-line) !important; border-radius: 4px !important; box-shadow: none !important; }
.skin-sgbook .pagination .page-link { border-radius: 3px !important; color: var(--sgb-text) !important; font-family: var(--sgb-num) !important; font-size: 1.05rem !important; border: 0 !important; background: transparent !important; box-shadow: none !important; }
.skin-sgbook .pagination .page-link.active { background: var(--sgb-cover) !important; color: var(--sgb-foil) !important; }

/* ── 단원(글) 화면 ── */
.skin-sgbook .sgb-crumb { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; padding: 26px 0 0; font-size: .86rem; color: var(--sgb-muted); }
.skin-sgbook .sgb-crumb a:hover { color: var(--sgb-cover); text-decoration: underline; }
.skin-sgbook .sgb-unit-head { max-width: 860px; padding: 30px 0 30px; border-bottom: 3px double var(--sgb-cover); margin-bottom: 36px; }
.skin-sgbook .sgb-unit-ch { margin: 0 0 16px; display: flex; flex-wrap: wrap; align-items: center; gap: 10px; font: 700 1rem/1.3 var(--sgb-serif); color: var(--sgb-cover); }
.skin-sgbook .sgb-unit-ch span { background: var(--sgb-cover); color: var(--sgb-foil); padding: 6px 10px; border-radius: 3px; }
.skin-sgbook .sgb-unit-ch small { font: 600 .74rem/1 var(--sgb-num); letter-spacing: .2em; color: var(--sgb-gold); }
.skin-sgbook .sgb-unit-title { margin: 0 0 16px; font-size: clamp(1.75rem, 3.4vw, 2.5rem); line-height: 1.35; word-break: keep-all; overflow-wrap: anywhere; }
.skin-sgbook .sgb-unit-layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 56px; align-items: start; }
.skin-sgbook .sgb-unit { min-width: 0; max-width: 780px; }
.skin-sgbook .sgb-objective { position: relative; margin: 0 0 34px; padding: 30px 24px 18px; background: var(--sgb-sage); border: 1.5px solid var(--sgb-cover); border-radius: 4px; }
.skin-sgbook .sgb-objective-tag {
    position: absolute; top: -15px; left: 18px; margin: 0; display: inline-flex; align-items: center; gap: 6px;
    background: var(--sgb-cover); color: #FBF3DF; font: 700 .9rem/1 var(--sgb-serif); padding: 7px 12px; border-radius: 3px;
}
.skin-sgbook .sgb-objective ol { margin: 0; padding: 0; list-style: none; counter-reset: sgbobj; }
.skin-sgbook .sgb-objective li { counter-increment: sgbobj; display: flex; gap: 10px; padding: 6px 0; line-height: 1.6; font-size: .97rem; color: var(--sgb-text); border-bottom: 1px dotted #B9C7B5; }
.skin-sgbook .sgb-objective li:last-child { border-bottom: 0; }
.skin-sgbook .sgb-objective li::before { content: counter(sgbobj) '.'; flex: 0 0 22px; font: 600 1.05rem/1.5 var(--sgb-num); color: var(--sgb-cover); }
.skin-sgbook .sgb-unit-fig { margin: 0 0 34px; }
.skin-sgbook .sgb-unit-fig .sgb-fig-frame { aspect-ratio: 16 / 8; }

.skin-sgbook .sgb-body { counter-reset: sgbh2; color: var(--sgb-text); font-size: 1.08rem; line-height: 1.9; word-break: keep-all; overflow-wrap: anywhere; }
.skin-sgbook .sgb-body p { margin: 0 0 1.25em; }
.skin-sgbook .sgb-body h2 {
    counter-increment: sgbh2; counter-reset: sgbh3; margin: 2.4em 0 .9em; padding-top: 18px; border-top: 1px solid var(--sgb-line);
    font-size: 1.55rem; line-height: 1.45; display: flex; gap: 12px; align-items: baseline;
}
.skin-sgbook .sgb-body h2:first-child { margin-top: 0; }
.skin-sgbook .sgb-body h2::before { content: counter(sgbh2); flex: 0 0 auto; font: 600 1.7rem/1 var(--sgb-num); color: var(--sgb-gold); min-width: 1.1em; }
.skin-sgbook .sgb-body h3 { counter-increment: sgbh3; margin: 1.9em 0 .7em; font-size: 1.22rem; line-height: 1.5; color: var(--sgb-cover); }
.skin-sgbook .sgb-body h3::before { content: counter(sgbh2) '.' counter(sgbh3) ' '; font: 600 1.15rem/1 var(--sgb-num); color: var(--sgb-gold); margin-right: 6px; }
.skin-sgbook .sgb-body h4 { margin: 1.6em 0 .6em; font-size: 1.08rem; }
.skin-sgbook .sgb-body strong, .skin-sgbook .sgb-body b { color: var(--sgb-ink); background: linear-gradient(transparent 62%, var(--sgb-marker) 62%); }
.skin-sgbook .sgb-body a { color: var(--sgb-cover); border-bottom: 1px solid var(--sgb-gold-lt); font-weight: 600; }
.skin-sgbook .sgb-body a:hover { color: var(--sgb-deep); border-bottom-color: var(--sgb-cover); }
.skin-sgbook .sgb-body ul, .skin-sgbook .sgb-body ol { margin: 0 0 1.4em; padding-left: 1.4em; }
.skin-sgbook .sgb-body ul { list-style: none; padding-left: 1.3em; }
.skin-sgbook .sgb-body ul > li { position: relative; }
.skin-sgbook .sgb-body ul > li::before { content: ''; position: absolute; left: -1.1em; top: .78em; width: 7px; height: 7px; background: var(--sgb-cover); transform: rotate(45deg); }
.skin-sgbook .sgb-body ol > li::marker { font-family: var(--sgb-num); font-weight: 600; color: var(--sgb-gold); }
.skin-sgbook .sgb-body li { margin: .4em 0; }
.skin-sgbook .sgb-body blockquote { margin: 1.6em 0; padding: 18px 22px; background: #FFF8E4; border-left: 4px solid var(--sgb-gold); border-radius: 0 4px 4px 0; color: var(--sgb-text); }
.skin-sgbook .sgb-body blockquote p:last-child { margin-bottom: 0; }
.skin-sgbook .sgb-body table { width: 100%; border-collapse: collapse; margin: 1.6em 0; font-size: .95rem; display: block; overflow-x: auto; }
.skin-sgbook .sgb-body th, .skin-sgbook .sgb-body td { border: 1px solid var(--sgb-line); padding: 10px 12px; text-align: left; vertical-align: top; }
.skin-sgbook .sgb-body th { background: var(--sgb-sage); color: var(--sgb-ink); font-family: var(--sgb-serif); }
.skin-sgbook .sgb-body img { max-width: 100%; height: auto; border: 1px solid var(--sgb-line); }
.skin-sgbook .sgb-body pre, .skin-sgbook .sgb-body code { white-space: pre-wrap; word-break: break-all; }
.skin-sgbook .sgb-notes { margin-top: 48px; padding-top: 16px; position: relative; font-size: .86rem; line-height: 1.7; color: var(--sgb-muted); }
.skin-sgbook .sgb-notes::before { content: ''; position: absolute; top: 0; left: 0; width: 34%; border-top: 1px solid #A9A08A; }
.skin-sgbook .sgb-notes p { margin: 0 0 4px; }
.skin-sgbook .sgb-notes sup { font: 600 .8rem/1 var(--sgb-num); color: var(--sgb-gold); margin-right: 5px; }

.skin-sgbook .sgb-rail { min-width: 0; }
.skin-sgbook .sgb-rail-sticky { position: sticky; top: 100px; display: grid; gap: 18px; }
.skin-sgbook .sgb-rail-card { position: relative; background: var(--sgb-page); border: 1px solid var(--sgb-line); border-radius: 4px; padding: 22px; }
.skin-sgbook .sgb-rail-chapter { background: var(--sgb-cover); border-color: var(--sgb-cover); color: #D3DDD0; }
.skin-sgbook .sgb-rail-ribbon { position: absolute; top: -1px; right: 22px; width: 18px; height: 46px; background: var(--sgb-gold-lt); clip-path: polygon(0 0, 100% 0, 100% 100%, 50% 78%, 0 100%); }
.skin-sgbook .sgb-rail-label { margin: 0 0 10px; font: 700 .8rem/1 var(--sgb-serif); color: var(--sgb-gold); }
.skin-sgbook .sgb-rail-chapter .sgb-rail-label { color: var(--sgb-gold-lt); }
.skin-sgbook .sgb-rail-chapter h2 { margin: 0 40px 10px 0; color: #FBF3DF; font-size: 1.35rem; line-height: 1.35; word-break: keep-all; }
.skin-sgbook .sgb-rail-chapter h2 small { display: block; font-size: .85rem; color: var(--sgb-foil); margin-bottom: 4px; }
.skin-sgbook .sgb-rail-chapter p:not(.sgb-rail-label) { margin: 0 0 18px; font-size: .9rem; line-height: 1.65; word-break: keep-all; }
.skin-sgbook .sgb-rail-chapter .sgb-btn { background: var(--sgb-gold-lt); color: var(--sgb-deep); width: 100%; }
.skin-sgbook .sgb-rail-list { list-style: none; margin: 0; padding: 0; }
.skin-sgbook .sgb-rail-list a { display: flex; gap: 10px; align-items: baseline; padding: 10px 0; border-bottom: 1px dotted #CFC5A8; font-family: var(--sgb-serif); color: var(--sgb-ink); word-break: keep-all; }
.skin-sgbook .sgb-rail-list li:last-child a { border-bottom: 0; }
.skin-sgbook .sgb-rail-list span { flex: 0 0 auto; font-size: .8rem; color: var(--sgb-gold); }
.skin-sgbook .sgb-rail-list a:hover { color: var(--sgb-cover); }
.skin-sgbook .sgb-related { padding-top: 64px; }

/* ── 장(분류) 화면: 장 표제지 ── */
.skin-sgbook .sgb-opener { display: grid; grid-template-columns: 200px minmax(0, 1fr); gap: 40px; align-items: stretch; margin: 26px 0 30px; }
.skin-sgbook .sgb-opener-num {
    display: flex; flex-direction: column; justify-content: flex-end; padding: 22px; min-height: 220px; border-radius: 4px;
    background: var(--sgb-cover); color: var(--sgb-foil);
    background-image: linear-gradient(90deg, transparent 0 14px, rgba(226, 184, 90, .6) 14px 16px, transparent 16px 20px, rgba(226, 184, 90, .4) 20px 21px, transparent 21px);
}
.skin-sgbook .sgb-opener-num small { font: 600 .78rem/1 var(--sgb-num); letter-spacing: .26em; color: #C7D2C3; padding-left: 16px; }
.skin-sgbook .sgb-opener-num span { font: 600 7rem/.9 var(--sgb-num); padding-left: 12px; }
.skin-sgbook .sgb-opener-copy { min-width: 0; display: flex; flex-direction: column; justify-content: center; padding: 10px 0; border-bottom: 3px double var(--sgb-cover); }
.skin-sgbook .sgb-opener-en { margin: 0 0 10px; font: 600 .82rem/1 var(--sgb-num); letter-spacing: .24em; color: var(--sgb-gold); }
.skin-sgbook .sgb-opener-title { margin: 0; font-size: clamp(2rem, 4vw, 2.9rem); line-height: 1.3; word-break: keep-all; overflow-wrap: anywhere; }
.skin-sgbook .sgb-opener-title span { display: block; font-size: 1.05rem; color: var(--sgb-cover); margin-bottom: 6px; }
.skin-sgbook .sgb-opener-desc { margin: 14px 0 0; font-size: 1.05rem; line-height: 1.75; color: var(--sgb-text); word-break: keep-all; max-width: 40em; }
.skin-sgbook .sgb-opener-count { margin: 16px 0 6px; color: var(--sgb-muted); font-size: .92rem; }
.skin-sgbook .sgb-opener-count b { font: 600 1.4rem/1 var(--sgb-num); color: var(--sgb-cover); margin: 0 2px; }

.skin-sgbook .sgb-tabs { display: flex; flex-wrap: wrap; gap: 6px; margin: 0 0 28px; border-bottom: 2px solid var(--sgb-cover); }
.skin-sgbook .sgb-tab {
    display: inline-flex; align-items: center; gap: 8px; padding: 10px 16px; min-height: 44px; border-radius: 5px 5px 0 0;
    background: #EFE8D6; color: var(--sgb-text); font: 700 .95rem/1.2 var(--sgb-serif); max-width: 100%;
}
.skin-sgbook .sgb-tab span { font: 600 .95rem/1 var(--sgb-num); color: var(--sgb-gold); }
.skin-sgbook .sgb-tab:hover { background: #E6DDC5; }
.skin-sgbook .sgb-tab.is-active { background: var(--sgb-cover); color: #FBF3DF; }
.skin-sgbook .sgb-tab.is-active span { color: var(--sgb-foil); }

.skin-sgbook .sgb-units { list-style: none; margin: 0; padding: 0; background: var(--sgb-page); border: 1px solid var(--sgb-line); border-radius: 4px; }
.skin-sgbook .sgb-units li + li { border-top: 1px dotted #CFC5A8; }
.skin-sgbook .sgb-units a { display: grid; grid-template-columns: 72px minmax(0, 1fr) 28px; gap: 18px; align-items: start; padding: 22px 26px; transition: background .2s; }
.skin-sgbook .sgb-units a:hover { background: #FFF9EA; }
.skin-sgbook .sgb-units-no { font: 600 1.5rem/1.3 var(--sgb-num); color: var(--sgb-gold); }
.skin-sgbook .sgb-units-body { min-width: 0; display: flex; flex-direction: column; gap: 6px; }
.skin-sgbook .sgb-units-title { font: 700 1.2rem/1.45 var(--sgb-serif); color: var(--sgb-ink); word-break: keep-all; overflow-wrap: anywhere; }
.skin-sgbook .sgb-units a:hover .sgb-units-title { color: var(--sgb-cover); }
.skin-sgbook .sgb-units-excerpt { color: var(--sgb-muted); font-size: .94rem; line-height: 1.7; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.skin-sgbook .sgb-units-go { color: var(--sgb-cover); padding-top: 4px; }

/* ── 태블릿 ── */
@media (max-width: 1080px) {
    .skin-sgbook .sgb-pages { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .skin-sgbook .sgb-unit-layout { grid-template-columns: minmax(0, 1fr) 260px; gap: 36px; }
    .skin-sgbook .sgb-how-inner { grid-template-columns: 1fr; gap: 26px; }
}

/* ── 모바일 ── */
@media (max-width: 768px) {
    .skin-sgbook .main-header::after { width: calc(100% - 32px); }
    .skin-sgbook .main-header .containerHeader { min-height: 62px; padding: 0 16px; }
    .skin-sgbook .main-header .brand-logo, .skin-sgbook .main-header .brand-logo a { font-size: 1.22rem; }
    .skin-sgbook .main-header .brand-logo a::before { width: 30px; height: 30px; flex-basis: 30px; }
    .skin-sgbook .main-header .menu-toggle { display: inline-flex !important; align-items: center; justify-content: center; }
    .skin-sgbook main.container { padding: 0 18px; }

    .skin-sgbook .sgb-hero { grid-template-columns: 1fr; gap: 26px; padding: 50px 6px 96px; }
    .skin-sgbook .sgb-hero::after { top: 12px; bottom: 12px; left: calc(50% - 50vw + 10px); right: calc(50% - 50vw + 10px); }
    .skin-sgbook .sgb-edition { margin-bottom: 16px; font-size: .76rem; }
    .skin-sgbook .sgb-hero-title { font-size: 1.95rem; }
    .skin-sgbook .sgb-hero-lead { font-size: 1rem; margin-top: 16px; }
    .skin-sgbook .sgb-hero-cta { margin-top: 24px; }
    .skin-sgbook .sgb-hero-cta .sgb-btn { flex: 1 1 140px; padding: 0 14px; white-space: nowrap; }
    .skin-sgbook .sgb-hero-facts { margin: 26px 0 14px; }
    .skin-sgbook .sgb-hero-facts li { padding: 0 14px; }
    .skin-sgbook .sgb-hero-facts b { font-size: 1.45rem; }
    .skin-sgbook .sgb-hero-visual { max-width: 440px; margin: 0 auto; width: 100%; }

    .skin-sgbook .sgb-goals { margin-top: -48px; padding: 32px 18px 16px; }
    .skin-sgbook .sgb-goals-tag { left: 16px; }
    .skin-sgbook .sgb-goals ol { grid-template-columns: 1fr; gap: 12px; }

    .skin-sgbook .sgb-section { padding-top: 56px; }
    .skin-sgbook .sgb-sec-title { font-size: 1.65rem; }

    .skin-sgbook .sgb-toc-no { flex-basis: 64px; font-size: 2rem; background-image: linear-gradient(90deg, transparent 0 6px, rgba(226, 184, 90, .5) 6px 8px, transparent 8px); }
    .skin-sgbook .sgb-toc-no small { font-size: .5rem; letter-spacing: .12em; }
    .skin-sgbook .sgb-toc-text { padding: 16px 16px; }
    .skin-sgbook .sgb-toc-line strong { font-size: 1.15rem; }
    .skin-sgbook .sgb-toc-desc { font-size: .88rem; }
    .skin-sgbook .sgb-toc-secs { padding: 2px 16px 10px 16px; }
    .skin-sgbook .sgb-toc-sno { flex-basis: 32px; }
    .skin-sgbook .sgb-toc-stitle { white-space: normal; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; font-size: .93rem; }

    .skin-sgbook .sgb-lead { margin-right: 8px; }
    .skin-sgbook .sgb-lead-link { grid-template-columns: 1fr; gap: 20px; padding: 18px; }
    .skin-sgbook .sgb-lead-title { font-size: 1.4rem; }
    .skin-sgbook .sgb-pages { grid-template-columns: 1fr; gap: 14px; }
    .skin-sgbook .sgb-page-link { padding: 14px 18px 12px; }
    .skin-sgbook .sgb-page-no { margin-top: 10px; font-size: 1.6rem; }
    .skin-sgbook .sgb-page-title { font-size: 1.1rem; }
    .skin-sgbook .sgb-page-excerpt { -webkit-line-clamp: 2; margin: 6px 0 12px; }

    .skin-sgbook .sgb-how { margin-top: 64px; padding: 48px 0; }
    .skin-sgbook .sgb-how-intro h2 { font-size: 1.65rem; }
    .skin-sgbook .sgb-how-steps { grid-template-columns: 1fr; gap: 12px; }

    .skin-sgbook .sgb-spine-1, .skin-sgbook .sgb-spine-2, .skin-sgbook .sgb-spine-3 { margin: 0; }
    .skin-sgbook .sgb-spine:nth-child(odd) { margin-right: 10px; }
    .skin-sgbook .sgb-spine:nth-child(even) { margin-left: 10px; }
    .skin-sgbook .sgb-spine a { gap: 10px; padding: 12px 14px 12px 24px; }
    .skin-sgbook .sgb-spine-title { font-size: .94rem; }
    .skin-sgbook .sgb-spine-ch { display: none; }

    .skin-sgbook .sgb-blank { flex-direction: column; text-align: center; padding: 26px 18px; gap: 16px; }
    .skin-sgbook .sgb-blank-art { flex-basis: auto; width: 180px; }

    .skin-sgbook .sgb-colophon { margin-top: 64px; padding: 36px 0 28px; }
    .skin-sgbook .sgb-colophon-inner { grid-template-columns: 1fr; gap: 22px; padding: 20px 16px; }
    .skin-sgbook .sgb-colophon-dl { grid-template-columns: 1fr; gap: 4px; }
    .skin-sgbook .sgb-colophon-dl dt { border-right: 0; margin-top: 10px; }
    .skin-sgbook footer { padding-bottom: 26px; }

    .skin-sgbook .sgb-unit-head { padding: 20px 0 22px; margin-bottom: 28px; }
    .skin-sgbook .sgb-unit-title { font-size: 1.6rem; }
    .skin-sgbook .sgb-unit-layout { grid-template-columns: 1fr; gap: 40px; }
    .skin-sgbook .sgb-rail-sticky { position: static; }
    .skin-sgbook .sgb-body { font-size: 1.03rem; line-height: 1.85; }
    .skin-sgbook .sgb-body h2 { font-size: 1.32rem; }
    .skin-sgbook .sgb-body h2::before { font-size: 1.45rem; }
    .skin-sgbook .sgb-objective { padding: 28px 16px 12px; }

    .skin-sgbook .sgb-opener { grid-template-columns: 1fr; gap: 0; margin-top: 18px; }
    .skin-sgbook .sgb-opener-num { min-height: 0; flex-direction: row; align-items: flex-end; justify-content: space-between; padding: 16px 18px 14px 30px; border-radius: 4px 4px 0 0; }
    .skin-sgbook .sgb-opener-num small { padding: 0 0 6px; }
    .skin-sgbook .sgb-opener-num span { font-size: 4rem; padding: 0; }
    .skin-sgbook .sgb-opener-copy { padding: 20px 0 18px; }
    .skin-sgbook .sgb-tabs { flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none; margin-right: -18px; padding-right: 18px; }
    .skin-sgbook .sgb-tab { flex: 0 0 auto; white-space: nowrap; }
    .skin-sgbook .sgb-units a { grid-template-columns: 1fr; gap: 6px; padding: 18px 16px; }
    .skin-sgbook .sgb-units-go { display: none; }
}