/* =============================================================================
   deathnote · base.css (B) — 디자인 토큰(:root) · 리셋 · 헤더/바닥글 내부 · section.seo · 토스트 · sr-only · noscript · 404
   SPEC §18: A 는 이 토큰을 var() 로만 쓴다. B 의 클래스: dn-top dn-h1 dn-icon-btn dn-foot seo dn-toast sr-only dn-noscript dn-404*
   .dn-app 의 grid-template 과 툴바 · 무대 · 쪽 이동 배치는 A 의 book.css — 여기서는 grid-area(header · foot)만 정한다(§2.1).
   바탕은 언제나 어두운 책상(color-scheme: dark) — 책은 물건이라 라이트/다크 테마를 따르지 않는다.
   ========================================================================== */
:root {
  color-scheme: dark;
  --dn-desk: #0b0b0c;
  --dn-bar: #151517;
  --dn-bar-2: #1e1e21;
  --dn-line-ui: #2c2c31;
  --dn-text: #ece7dc;
  --dn-dim: #a8a297;
  --dn-accent: #b3261e;          /* 활성 도구 · 선택 — 흰 글자 대비 6.8:1 */
  --dn-accent-ink: #ffffff;
  --dn-focus: #f4d06f;
  --dn-danger: #ff6b6b;          /* 위험 글자 */
  --dn-danger-bg: #8f1d19;       /* 위험 버튼 바탕 */
  --dn-radius: 10px;
  --dn-shadow: 0 18px 40px rgba(0, 0, 0, .55);
  --dn-ink: #141414;
  --dn-paper-aged: #e8dcc0;
  --dn-paper-clean: #f6f3ea;
  --dn-rule: rgba(64, 52, 40, .38);
  --dn-print: #2a241c;           /* 규칙 본문 */
  --dn-pno: #5e5343;             /* 쪽 번호 */
  --dn-cover: #0e0e0f;
  --dn-cover-title: #f2f0ea;
  --dn-font-title: "DN Grenze Gotisch", serif;
  /* 화면 UI 글꼴 = 시스템 서체(내려받기 0). CJK 는 아래 :lang() 에서 그 언어 글리프 모양이 먼저 오도록 순서를 바꾼다 */
  --dn-font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", system-ui, sans-serif;
}
:root:lang(ja) { --dn-font-ui: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", "Yu Gothic", YuGothic, Meiryo, "Noto Sans JP", "Noto Sans CJK JP", system-ui, sans-serif; }
:root:lang(ko) { --dn-font-ui: "Apple SD Gothic Neo", "Malgun Gothic", "Noto Sans KR", "Noto Sans CJK KR", system-ui, sans-serif; }
:root:lang(zh-Hans) { --dn-font-ui: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Noto Sans CJK SC", system-ui, sans-serif; }
:root:lang(zh-Hant) { --dn-font-ui: "PingFang TC", "Microsoft JhengHei", "Noto Sans TC", "Noto Sans CJK TC", system-ui, sans-serif; }
:root:lang(th) { --dn-font-ui: "Thonburi", "Leelawadee UI", "Noto Sans Thai", Tahoma, system-ui, sans-serif; }

/* ── 리셋 ── */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--dn-desk);
  color: var(--dn-text);
  font-family: var(--dn-font-ui);
  font-size: 1rem;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}
button, input, select, textarea { font: inherit; color: inherit; }
[hidden] { display: none !important; }
:focus { outline: none; }
:focus-visible { outline: 2px solid var(--dn-focus); outline-offset: 2px; }
a { color: inherit; }

/* ── 헤더(정적 · 우측 상단 톱니) ── */
.dn-top {
  grid-area: header;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-width: 0;
  min-height: 48px;
  padding: env(safe-area-inset-top, 0px) max(16px, env(safe-area-inset-right, 0px)) 0 max(16px, env(safe-area-inset-left, 0px));
  background: var(--dn-bar);
  border-bottom: 1px solid var(--dn-line-ui);
}
.dn-h1 {
  margin: 0;
  min-width: 0;
  font-size: 1.0625rem;
  font-weight: 700;
  letter-spacing: .04em;
  line-height: 1.3;
  color: var(--dn-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.dn-icon-btn {
  flex: 0 0 auto;
  display: inline-grid;
  place-items: center;
  inline-size: 44px;
  block-size: 44px;
  margin-right: -6px;
  padding: 0;
  border: 0;
  border-radius: var(--dn-radius);
  background: transparent;
  color: var(--dn-text);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}
.dn-icon-btn:hover { background: var(--dn-bar-2); }
.dn-icon-btn:active { background: var(--dn-line-ui); }
.dn-icon-btn svg { display: block; }

/* ── 바닥글(정적) ── */
.dn-foot {
  grid-area: foot;
  min-width: 0;
  padding: 4px 16px calc(6px + env(safe-area-inset-bottom, 0px));
  font-size: .75rem;
  line-height: 1.6;
  color: var(--dn-dim);
  text-align: center;
}
.dn-foot a { color: var(--dn-dim); text-decoration: underline; text-underline-offset: 2px; }
.dn-foot a:hover { color: var(--dn-text); }
.dn-foot .dn-sep { padding: 0 .35em; opacity: .7; }
@media (max-width: 479px) { .dn-foot { font-size: .6875rem; } }

/* ── 크롤러 · JS 없이 읽히는 설명(첫 화면 밖 · packages/seo L6) ── */
.seo {
  border-top: 1px solid var(--dn-line-ui);
  background: #101012;
  color: var(--dn-text);
  padding: 40px 16px 56px;
}
.seo-in { max-width: 760px; margin: 0 auto; }
.seo h2 { margin: 0 0 12px; font-size: 1.375rem; line-height: 1.35; letter-spacing: .02em; }
.seo h3 { margin: 30px 0 8px; font-size: 1.0625rem; line-height: 1.4; }
.seo h4 { margin: 18px 0 4px; font-size: 1rem; line-height: 1.45; color: var(--dn-text); }
.seo p, .seo li { margin: 0 0 8px; line-height: 1.8; color: #d9d3c7; }
.seo .how { margin: 0; padding-left: 1.4em; }
.seo .how li { padding-left: .2em; }
.seo .faq p { margin-bottom: 4px; }
.seo .fine { margin-top: 26px; font-size: .8125rem; line-height: 1.7; color: var(--dn-dim); }
.seo .fine + .fine { margin-top: 6px; }
.seo a { color: var(--dn-text); text-underline-offset: 2px; }

/* ── 토스트(DN_CORE.toast — 쪽 이동 위 · 좁은 화면은 툴바 위) ──
   가운데 맞춤은 left/right 0 + margin auto + width max-content(left: 50% 로 두면 shrink-to-fit 폭이 화면 절반에 묶여 3줄로 접혔다) */
.dn-toast {
  position: fixed;
  left: 0;
  right: 0;
  margin-inline: auto;
  width: max-content;
  bottom: calc(var(--dn-toast-b, 112px) + env(safe-area-inset-bottom, 0px));
  z-index: 60;
  max-width: min(calc(100vw - 32px), 520px);
  padding: 10px 16px;
  border: 1px solid var(--dn-line-ui);
  border-radius: 14px;
  background: rgba(30, 30, 33, .97);
  box-shadow: var(--dn-shadow);
  color: var(--dn-text);
  font-size: .875rem;
  line-height: 1.5;
  text-align: center;
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity .2s ease, transform .2s ease;
}
.dn-toast.is-on { opacity: 1; transform: translateY(0); }
/* 900px 미만: 툴바(무대 아래) + 쪽 이동 + 바닥글 위로 · 보기 전용 배지(툴바 바로 위)와 겹치지 않게 더 위로 */
@media (max-width: 899.98px) { .dn-toast { --dn-toast-b: 160px; } body[data-view="1"] .dn-toast { --dn-toast-b: 196px; } }
.dn-toast:empty { display: none; }
@media (prefers-reduced-motion: reduce) { .dn-toast { transition: none; } }

/* ── 스크린 리더 전용 ── */
.sr-only {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0 0 0 0) !important;
  clip-path: inset(50%) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

/* ── JS 꺼짐 안내(무대 안) ── */
.dn-noscript {
  max-width: 30em;
  margin: 32px auto;
  padding: 16px 20px;
  border: 1px solid var(--dn-line-ui);
  border-radius: var(--dn-radius);
  background: var(--dn-bar);
  color: var(--dn-text);
  text-align: center;
  line-height: 1.7;
}

/* ── 404(어두운 책상 + CSS 로 그린 작은 닫힌 노트 · 글자 없음) ── */
.dn-404 {
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  place-items: center;
  padding: 40px 16px;
  background: radial-gradient(ellipse 70% 55% at 50% 38%, #1d1c1f 0%, var(--dn-desk) 70%);
  text-align: center;
}
.dn-404-in { max-width: 34em; }
.dn-404-book {
  position: relative;
  width: 112px;
  height: 156px;
  margin: 0 auto 30px;
  border-radius: 3px 7px 7px 3px;
  background:
    radial-gradient(ellipse 80% 60% at 40% 30%, rgba(255, 255, 255, .07), rgba(255, 255, 255, 0) 70%),
    linear-gradient(90deg, #050506 0 9px, rgba(255, 255, 255, .07) 9px 10px, transparent 10px),
    var(--dn-cover);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, .05), inset -3px -3px 6px rgba(0, 0, 0, .6), var(--dn-shadow);
  transform: rotate(-7deg);
}
.dn-404-book::before {          /* 종이 단면(오른쪽) */
  content: '';
  position: absolute;
  top: 5px;
  right: -4px;
  bottom: 5px;
  width: 4px;
  border-radius: 0 2px 2px 0;
  background: repeating-linear-gradient(180deg, #d8ccb0 0 1px, #b9ad92 1px 2px);
}
.dn-404-book::after {           /* 가름끈 */
  content: '';
  position: absolute;
  left: 68%;
  bottom: -22px;
  width: 8px;
  height: 34px;
  background: #7d1414;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 50% 80%, 0 100%);
}
.dn-404 h1 { margin: 0 0 10px; font-size: 1.375rem; line-height: 1.4; }
.dn-404 p { margin: 0 0 14px; line-height: 1.75; color: #d9d3c7; }
.dn-404-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  margin: 6px 0 18px;
  padding: 10px 22px;
  border-radius: 999px;
  background: var(--dn-accent);
  color: var(--dn-accent-ink);
  font-weight: 700;
  text-decoration: none;
}
.dn-404-btn:hover { filter: brightness(1.08); }
.dn-404 .fine { font-size: .8125rem; color: var(--dn-dim); }
.dn-404 .fine a { color: var(--dn-dim); }

@media (forced-colors: active) {
  .dn-icon-btn, .dn-404-btn { border: 1px solid ButtonText; }
  .dn-toast { border-color: CanvasText; }
}