/* FORGE AI Trail ポータル v3
   ムードシート（森緑・クリーム・セージ・ピーチの平面図形）に合わせた静かな学習サイト。
   グラデーション・半透明・浮き上がるホバーは使わない。ケルンの色（ティール・琥珀）はケルンだけに使う。 */
:root {
  color-scheme: light;
  --color-bg: #F6F5F1;
  --color-surface: #FFFFFF;
  --color-sidebar: #F3F3F2;
  --color-ink: #1A1C20;
  --color-body: #3A4540;
  --color-muted: #556660; /* was #6E7E7A; WCAG AA ≥4.5:1 on page/surface/sidebar/wash panels */
  --color-primary: #2F5D3A;
  --color-primary-dark: #1F5138;
  --color-primary-soft: #CEE6D6;
  --color-primary-wash: #EAF1EB;
  --color-sage: #6E8870;
  --color-peach: #F0A078;
  --color-peach-soft: #F8E8DC;
  --color-sand: #D0C6AC;
  --color-line: #E2E4DF;
  --color-line-strong: #CDD3CB;
  --color-amber: #F0A028;
  --color-red: #B5523B;
  --radius: 10px;
  --radius-small: 6px;
  --sidebar-width: 232px;
  --article-scroll-offset: 32px;
  font-family: 'Noto Sans JP', 'Hiragino Sans', 'Hiragino Kaku Gothic ProN', 'Yu Gothic', YuGothic, Meiryo, system-ui, sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  scroll-padding-top: var(--article-scroll-offset);
}

* { box-sizing: border-box; }
body { margin: 0; color: var(--color-body); background: var(--color-bg); font-size: 15px; line-height: 1.85; overflow-wrap: anywhere; }
body, h1, h2, h3, h4, p, ul, ol, figure { margin-block-start: 0; }
h1, h2, h3, h4 { color: var(--color-ink); font-weight: 700; line-height: 1.5; letter-spacing: .02em; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
a { color: var(--color-primary); text-underline-offset: .25em; text-decoration-thickness: 1px; }
a:hover { color: var(--color-primary-dark); }
img, svg { max-width: 100%; vertical-align: middle; }
button, a, input, summary { -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 3px; }
::selection { background: var(--color-primary-soft); color: var(--color-ink); }
main { min-height: 55vh; }
main:focus { outline: none; }
.container { width: min(1080px, calc(100% - 40px)); margin-inline: auto; }
.skip-link { position: fixed; top: 12px; left: 12px; z-index: 100; padding: 8px 16px; color: #fff; background: var(--color-primary-dark); border-radius: var(--radius-small); transform: translateY(-180%); }
.skip-link:focus { transform: translateY(0); }

/* 下書きバナー：目立たせすぎず、確実に読める砂色の帯 */
.draft-banner { padding: 6px 16px; color: #5E5232; background: #EFEADB; border-bottom: 1px solid #E0D8C2; font-size: 12px; font-weight: 600; text-align: center; letter-spacing: .03em; }

/* ---------- 骨格：モバイルは上部バー、デスクトップは左サイドバー ---------- */
.site-header { display: flex; flex-wrap: wrap; align-items: center; gap: 4px 16px; padding: 12px 20px 0; background: var(--color-surface); border-bottom: 1px solid var(--color-line); }
.brand { display: inline-flex; align-items: center; gap: 10px; padding-block: 4px; color: var(--color-ink); text-decoration: none; }
.brand:hover { color: var(--color-ink); }
.brand-mark { flex-shrink: 0; width: 30px; height: 33px; }
.brand-name { font-size: 16px; font-weight: 700; letter-spacing: .02em; white-space: nowrap; }
.site-nav { display: flex; width: calc(100% + 16px); gap: 2px; margin-inline: -8px; overflow-x: auto; scrollbar-width: none; }
.site-nav::-webkit-scrollbar { display: none; }
.site-nav a { position: relative; display: inline-flex; align-items: center; gap: 8px; padding: 10px 10px 12px; color: var(--color-body); font-size: 13px; font-weight: 500; text-decoration: none; white-space: nowrap; }
.site-nav a:hover { color: var(--color-primary); }
.site-nav a[aria-current='page'] { color: var(--color-primary-dark); font-weight: 700; }
.site-nav a[aria-current='page']::after { position: absolute; right: 10px; bottom: 0; left: 10px; height: 2px; background: var(--color-primary); content: ''; }
.nav-icon { display: none; flex-shrink: 0; width: 18px; height: 18px; }
.sidebar-note { display: none; }
.nav-toggle, .nav-backdrop { display: none; }
.app-main { min-width: 0; }

/* JS なしでは縦並びのリンク、初期化後は同じ nav を開閉パネルとして使う。 */
@media (max-width: 959px) {
  .site-header { justify-content: space-between; gap: 12px 16px; padding-block: 12px; }
  .brand { min-width: 0; }
  .brand-name { white-space: normal; }
  .site-nav { flex-direction: column; width: 100%; gap: 4px; margin: 0; overflow: visible; }
  .site-nav a { min-height: 44px; padding: 10px 14px; border-radius: var(--radius-small); font-size: 15px; white-space: normal; }
  .site-nav a:hover, .site-nav a[aria-current='page'] { background: var(--color-primary-wash); }
  .site-nav a[aria-current='page']::after { display: none; }
  .nav-ready .nav-toggle:not([hidden]) { position: relative; z-index: 82; display: inline-flex; flex-shrink: 0; align-items: center; justify-content: center; width: 44px; height: 44px; padding: 10px; border: 1px solid var(--color-line-strong); border-radius: var(--radius-small); color: var(--color-primary); background: var(--color-bg); }
  .nav-toggle:hover, .nav-toggle[aria-expanded='true'] { border-color: var(--color-primary); background: var(--color-primary-wash); }
  .nav-ready:not(.nav-open) .site-nav { display: none; }
  .nav-ready .site-nav { position: fixed; z-index: 82; top: var(--nav-panel-top, 80px); right: 16px; width: min(320px, calc(100% - 32px)); max-height: calc(100dvh - var(--nav-panel-top, 80px) - 16px); padding: 12px; border: 1px solid var(--color-line-strong); border-radius: var(--radius-small); background: var(--color-bg); overflow-y: auto; overscroll-behavior: contain; }
  .nav-backdrop:not([hidden]) { position: fixed; z-index: 81; inset: 0; display: block; background: rgb(26 28 32 / 12%); }
}

@media (min-width: 960px) {
  .app { display: grid; grid-template-columns: var(--sidebar-width) minmax(0, 1fr); min-height: 100vh; }
  .site-header { position: sticky; top: 0; flex-direction: column; flex-wrap: nowrap; align-items: stretch; gap: 0; height: 100vh; padding: 26px 16px 24px; background: var(--color-sidebar); border-right: 1px solid var(--color-line); border-bottom: 0; }
  .brand { margin: 0 8px 30px; }
  .site-nav { flex-direction: column; gap: 4px; margin: 0; overflow: visible; }
  .site-nav a { gap: 12px; padding: 9px 12px; border-radius: 8px; font-size: 14px; }
  .site-nav a:hover { background: #EAEBE7; }
  .site-nav a[aria-current='page'] { background: var(--color-primary-wash); }
  .site-nav a[aria-current='page']::after { display: none; }
  .nav-icon { display: block; color: var(--color-muted); }
  .site-nav a[aria-current='page'] .nav-icon, .site-nav a:hover .nav-icon { color: var(--color-primary); }
  .sidebar-note { display: block; margin: auto 12px 0; padding-top: 18px; border-top: 1px solid var(--color-line); color: var(--color-muted); font-size: 12px; line-height: 1.8; }
  .container { width: min(1040px, calc(100% - 96px)); }
}

/* ---------- 文字まわり ---------- */
.page-label { margin-bottom: 10px; color: var(--color-muted); font-size: 13px; font-weight: 500; }
.page-header { padding: 48px 0 28px; }
.page-header h1 { margin-bottom: 12px; font-size: clamp(26px, 3.2vw, 34px); line-height: 1.45; }
.page-header p:last-child { margin-bottom: 0; }
.lead { max-width: 640px; color: var(--color-muted); font-size: 15px; line-height: 1.95; }
.panel-label { display: inline-block; margin-bottom: 10px; padding: 1px 12px; border: 1px solid var(--color-primary-soft); border-radius: 999px; color: var(--color-primary); background: var(--color-primary-wash); font-size: 12px; font-weight: 600; line-height: 1.9; }
.panel-note { margin: 18px 0 0; color: var(--color-muted); font-size: 12px; }
.text-link { display: inline-flex; align-items: center; gap: 6px; color: var(--color-primary); font-size: 13px; font-weight: 600; text-decoration: underline; text-decoration-color: var(--color-primary-soft); text-underline-offset: .35em; }
.text-link:hover { text-decoration-color: currentColor; }

/* ---------- ボタン ---------- */
.button { display: inline-flex; min-height: 44px; align-items: center; justify-content: center; padding: 10px 22px; border: 1px solid var(--color-primary); border-radius: 8px; color: #fff; background: var(--color-primary); font-size: 14px; font-weight: 600; line-height: 1.6; text-decoration: none; transition: background-color .15s ease, border-color .15s ease; }
.button:hover { color: #fff; background: var(--color-primary-dark); border-color: var(--color-primary-dark); }
.button-secondary { display: inline-flex; min-height: 44px; align-items: center; justify-content: center; padding: 10px 18px; border: 1px solid var(--color-line-strong); border-radius: 8px; color: var(--color-ink); background: var(--color-surface); font-size: 14px; font-weight: 600; transition: background-color .15s ease, border-color .15s ease; }
.button-secondary:hover { color: var(--color-ink); background: #F1F3EF; border-color: var(--color-sage); }

/* ---------- ホーム ---------- */
.home-hero { display: grid; gap: 28px; padding: 32px 0 28px; }
.home-hero h1 { margin-bottom: 16px; font-size: clamp(30px, 7.4vw, 44px); font-weight: 800; line-height: 1.4; letter-spacing: .03em; }
.home-hero .lead { margin-bottom: 26px; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 22px; }
.home-art { overflow: hidden; aspect-ratio: 480 / 380; border-radius: var(--radius); background: #E7ECE3; }
.home-art > svg { display: block; width: 100%; height: 100%; }
/* モバイルは小さな積み石を拡大した別構図に差し替え（kernHeroArtMobile） */
.home-art > .home-art-mobile { display: none; }
@media (max-width: 480px) {
  .home-art > .home-art-desktop { display: none; }
  .home-art > .home-art-mobile { display: block; }
}
.steps { display: grid; gap: 0; margin: 0 0 8px; padding: 6px 22px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); list-style: none; }
.steps li { display: flex; align-items: flex-start; gap: 14px; padding: 14px 0; }
.steps li + li { border-top: 1px solid var(--color-line); }
.steps b { display: block; color: var(--color-ink); font-size: 15px; line-height: 1.6; }
.steps p { margin: 0; color: var(--color-muted); font-size: 13px; line-height: 1.7; }
.step-number { display: inline-flex; flex-shrink: 0; width: 28px; height: 28px; align-items: center; justify-content: center; margin-top: 1px; border-radius: 50%; color: var(--color-primary-dark); background: var(--color-primary-soft); font-size: 13px; font-weight: 700; }

@media (min-width: 760px) {
  .home-hero { grid-template-columns: minmax(0, .95fr) minmax(0, 1fr); align-items: center; gap: 40px; padding: 48px 0 36px; }
  .steps { grid-template-columns: repeat(3, minmax(0, 1fr)); padding: 4px 6px; }
  .steps li { padding: 18px 20px; }
  .steps li + li { border-top: 0; border-left: 1px solid var(--color-line); }
}

/* ---------- セクション ---------- */
.section { padding-block: 36px 40px; }
.section-heading { display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: 8px 20px; margin-bottom: 20px; }
.section-heading p { margin-bottom: 0; color: var(--color-muted); font-size: 13px; }
.section-title { margin-bottom: 0; font-size: 20px; line-height: 1.5; }

/* 横に続くカードは、スクリプトなしでもスワイプ・Tabでたどれる。 */
.collection-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 20px; }
.collection-actions > a { min-height: 44px; }
.carousel-controls { display: flex; gap: 8px; }
.carousel-button { display: inline-flex; min-width: 52px; min-height: 44px; align-items: center; justify-content: center; padding: 8px 12px; border: 1px solid var(--color-line-strong); border-radius: var(--radius-small); color: var(--color-primary); background: var(--color-bg); font-size: 13px; font-weight: 600; }
.carousel-button:hover:not(:disabled) { border-color: var(--color-primary); background: var(--color-primary-wash); }
.carousel-button:disabled { color: var(--color-muted); background: #EFEDE6; cursor: default; }
.carousel-button[hidden] { display: none; }
.carousel-track { display: flex; gap: 16px; min-width: 0; margin: 0; padding: 4px 4px 16px; list-style: none; overflow-x: auto; scroll-snap-type: x mandatory; scroll-padding-inline: 4px; overscroll-behavior-x: contain; }
.carousel-track > li { display: flex; flex: 0 0 86%; min-width: 0; scroll-snap-align: start; }
.carousel-track .article-card { width: 100%; }
.home-card-list { margin: 0; padding: 0; list-style: none; }
.home-card-list > li { display: flex; min-width: 0; }
.home-card-list .article-card { width: 100%; }
.home-collection .card-title a, .related-articles .card-title a { display: inline-flex; min-height: 44px; align-items: center; }
.home-collection .empty-state .text-link { min-height: 44px; }
@media (min-width: 640px) { .carousel-track > li { flex-basis: 60%; } }
@media (min-width: 1100px) { .carousel-track > li { flex-basis: 56%; } }

/* ---------- カード ---------- */
.card-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
.hub-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
@media (min-width: 640px) { .card-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (min-width: 760px) { .hub-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
.article-card, .hub-card { position: relative; display: flex; flex-direction: column; min-width: 0; overflow: hidden; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); transition: border-color .15s ease; }
.article-card:hover, a.hub-card:hover { border-color: var(--color-line-strong); }
.card-thumb { display: block; flex: none; width: 100%; height: auto; aspect-ratio: 320 / 128; background: var(--color-primary-wash); }
.card-body { display: flex; flex: 1; flex-direction: column; padding: 18px 20px 18px; }
.card-top { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin-bottom: 10px; }
.card-top:empty { display: none; }
.card-statuses { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; }
.card-title { margin-bottom: 8px; font-size: 17px; line-height: 1.65; }
.card-title a { color: inherit; text-decoration: none; }
.card-title a:hover { color: var(--color-primary); }
.card-title a::after { position: absolute; inset: 0; content: ''; }
.card-description { flex-grow: 1; margin-bottom: 16px; color: var(--color-muted); font-size: 13px; line-height: 1.85; }
.card-footer { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding-top: 12px; border-top: 1px solid var(--color-line); color: var(--color-muted); font-size: 12px; }
.card-footer span { color: var(--color-primary); font-weight: 600; }
.quiz-card .text-link { align-self: flex-start; }
a.hub-card { color: inherit; text-decoration: none; }
a.hub-card:hover { color: inherit; }
.hub-card h3 { margin-bottom: 6px; font-size: 16px; }
.hub-card p { flex-grow: 1; margin-bottom: 14px; color: var(--color-muted); font-size: 13px; line-height: 1.8; }
.hub-card .text-link { align-self: flex-start; }

/* タグとバッジ：細いピル。色は状態の意味があるときだけ */
.tag-list { display: flex; flex-wrap: wrap; gap: 6px; margin: 0; padding: 0; list-style: none; }
.tag { display: inline-flex; align-items: center; padding: 0 9px; border: 1px solid var(--color-line); border-radius: 999px; color: #4E6658; background: #F4F6F2; font-size: 11px; line-height: 1.9; }
.badge { display: inline-flex; align-items: center; padding: 0 9px; border: 1px solid var(--color-line); border-radius: 999px; color: var(--color-body); background: var(--color-surface); font-size: 11px; font-weight: 600; line-height: 1.9; }
.badge-review-draft_unreviewed { border-color: #EBC9AE; color: #84492A; background: var(--color-peach-soft); }
.badge-review-reviewed { border-color: #B9D6C3; color: var(--color-primary-dark); background: var(--color-primary-wash); }
.badge-review-revision_requested { border-color: #E3B3A5; color: #8E3A28; background: #FBEDE8; }
.badge-read { border-color: var(--color-line-strong); color: var(--color-muted); background: #F4F6F2; }
.badge-read[data-read-state='read'], .badge-read.is-read { border-color: #B9D6C3; color: var(--color-primary-dark); background: var(--color-primary-wash); }

/* ---------- 記事とクイズを探す ---------- */
.search-controls { display: grid; gap: 20px; margin-bottom: 24px; padding: 22px 20px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); }
.search-label { display: grid; gap: 8px; color: var(--color-ink); font-size: 14px; font-weight: 600; }
.search-input { display: block; width: 100%; min-width: 0; min-height: 48px; padding: 10px 14px; border: 1px solid var(--color-line-strong); border-radius: var(--radius-small); color: var(--color-ink); background: #FBFBF9; font-size: 16px; font-weight: 400; line-height: 1.6; }
.search-input::placeholder { color: var(--color-muted); }
.search-input:focus-visible { border-color: var(--color-primary); }
.search-tags { min-width: 0; margin: 0; padding: 0; border: 0; }
.search-tags legend { margin-bottom: 10px; padding: 0; color: var(--color-body); font-size: 13px; font-weight: 600; }
.tag-filters { display: flex; flex-wrap: wrap; gap: 8px; }
.tag-toggle { display: inline-flex; min-width: 44px; min-height: 44px; align-items: center; justify-content: center; padding: 8px 14px; border: 1px solid var(--color-line-strong); border-radius: 999px; color: var(--color-body); background: #F4F6F2; font-size: 13px; line-height: 1.6; }
.tag-toggle:hover { border-color: var(--color-sage); background: var(--color-primary-wash); }
.tag-toggle[aria-pressed='true'] { border-color: var(--color-primary); color: #fff; background: var(--color-primary); font-weight: 600; }
.search-controls > .button-secondary { justify-self: start; }
.search-count { margin: 0 0 18px; color: var(--color-muted); font-size: 13px; }
[data-search-empty] { margin-top: 20px; }
[data-search] [hidden], [data-read-article] [hidden], [data-read-reset][hidden] { display: none; }
@media (min-width: 760px) { .search-controls { padding: 26px 28px; } }

/* ---------- 空の状態（ケルンが案内） ---------- */
.empty-state { display: flex; align-items: flex-start; gap: 18px; padding: 24px 22px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); }
.empty-kern { flex-shrink: 0; width: 72px; height: 72px; overflow: visible; }
.empty-state h2, .empty-state h3 { margin-bottom: 6px; font-size: 17px; }
.empty-state p { max-width: 620px; margin-bottom: 14px; color: var(--color-muted); font-size: 14px; }

/* ---------- 記事 ---------- */
.breadcrumbs { padding: 18px 0 0; color: var(--color-muted); font-size: 12px; }
.breadcrumbs ol { display: flex; flex-wrap: wrap; gap: 0 10px; margin: 0; padding: 0; list-style: none; }
.breadcrumbs li { display: flex; min-width: 0; max-width: 100%; align-items: center; gap: 10px; }
.breadcrumbs li[aria-current='page'] { color: var(--color-body); }
.breadcrumbs li > span:last-child { min-width: 0; padding-block: 10px; }
.breadcrumb-separator { flex-shrink: 0; color: var(--color-muted); }
.breadcrumbs a { display: inline-flex; min-width: 44px; min-height: 44px; align-items: center; color: inherit; text-decoration: none; }
.breadcrumbs a:hover { color: var(--color-primary); text-decoration: underline; }
.breadcrumbs + script + .page-header { padding-top: 20px; }
.article-header { margin-bottom: 28px; padding: 22px 0 26px; border-bottom: 1px solid var(--color-line); }
.article-header h1 { max-width: 860px; margin: 12px 0 14px; font-size: clamp(25px, 3vw, 34px); line-height: 1.55; }
.article-header .lead { max-width: 760px; margin-bottom: 16px; font-size: 15px; }
.article-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 12px; color: var(--color-muted); font-size: 12px; }
.meta-id { color: var(--color-muted); font-size: 12px; font-weight: 600; letter-spacing: .04em; }
.draft-article-note { margin-bottom: 28px; padding: 14px 18px; border: 1px solid #EBC9AE; border-radius: var(--radius-small); color: #6E4026; background: var(--color-peach-soft); font-size: 13px; line-height: 1.9; }
.article-layout { display: grid; grid-template-columns: 1fr; gap: 28px; padding-bottom: 56px; }
.article-body { min-width: 0; }
.video-content { max-width: 860px; padding-bottom: 56px; }
.video-embed { aspect-ratio: 16 / 9; margin-bottom: 24px; overflow: hidden; border-radius: var(--radius); background: var(--color-ink); }
.video-embed iframe { display: block; width: 100%; height: 100%; border: 0; }
.article-toc { display: none; padding: 16px 14px; border: 1px solid var(--color-line); border-radius: var(--radius); color: var(--color-muted); background: var(--color-surface); font-size: 13px; }
.article-toc h2 { margin-bottom: 10px; color: var(--color-ink); font-size: 13px; }
.article-toc ol, .article-toc-mobile ol { margin: 0; padding-left: 20px; }
.article-toc li + li, .article-toc-mobile li + li { margin-top: 2px; }
.article-toc li::marker, .article-toc-mobile li::marker { color: var(--color-sage); }
.article-toc a, .article-toc-mobile a { display: flex; min-height: 44px; align-items: center; padding: 7px 8px; border-left: 2px solid transparent; border-radius: 0 var(--radius-small) var(--radius-small) 0; color: inherit; line-height: 1.6; text-decoration: none; }
.article-toc a:hover, .article-toc-mobile a:hover { color: var(--color-primary); text-decoration: underline; }
.article-toc a[aria-current='true'], .article-toc-mobile a[aria-current='true'] { border-left-color: var(--color-primary); color: var(--color-primary-dark); background: var(--color-primary-wash); font-weight: 600; }
.article-toc-mobile { margin-bottom: 28px; padding: 4px 18px; border: 1px solid var(--color-line); border-radius: var(--radius); color: var(--color-body); background: var(--color-surface); font-size: 13px; }
.article-toc-mobile summary { min-height: 44px; padding-block: 8px; color: var(--color-ink); font-size: 14px; font-weight: 600; cursor: pointer; }
.article-toc-mobile[open] { padding-bottom: 16px; }
.article-toc-mobile[open] summary { margin-bottom: 8px; border-bottom: 1px solid var(--color-line); }
@media (min-width: 960px) {
  .article-layout { grid-template-columns: minmax(0, 1fr) 190px; align-items: start; gap: 28px; }
  .article-toc { position: sticky; top: var(--article-scroll-offset); display: block; grid-row: auto; grid-column: 2; max-height: calc(100dvh - var(--article-scroll-offset) - 24px); overflow-y: auto; overscroll-behavior: contain; }
  .article-toc-mobile { display: none; }
}
@media (min-width: 1100px) {
  .article-layout { grid-template-columns: minmax(0, 1fr) 220px; gap: 40px; }
}

.prose { max-width: 70ch; font-size: 16px; line-height: 2; }
.prose > :first-child { margin-top: 0; }
.prose > :last-child { margin-bottom: 0; }
.prose p { margin-bottom: 22px; }
.prose h2 { margin-top: 48px; margin-bottom: 18px; padding-left: 14px; border-left: 3px solid var(--color-primary); font-size: 21px; line-height: 1.6; }
.prose h3 { margin-top: 32px; margin-bottom: 14px; font-size: 17px; }
.prose h4 { margin-top: 26px; margin-bottom: 12px; font-size: 16px; }
.prose ul, .prose ol { margin-bottom: 22px; padding-left: 1.5em; }
.prose li { padding-left: 3px; }
.prose li + li { margin-top: 6px; }
.prose li::marker { color: var(--color-sage); }
.prose li p { margin-bottom: 10px; }
.prose strong { color: var(--color-ink); font-weight: 700; }
.prose blockquote { margin: 26px 0; padding: 14px 20px; border-left: 3px solid var(--color-sand); border-radius: 0 var(--radius-small) var(--radius-small) 0; color: #4E5A54; background: #EFEDE6; }
.prose blockquote p:last-child { margin-bottom: 0; }
.prose code { padding: 1px 5px; border: 1px solid var(--color-line); border-radius: 4px; color: #3E4C45; background: #F1F2EE; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: .86em; }
.prose pre { max-width: 100%; margin-bottom: 24px; padding: 18px; border: 1px solid var(--color-line); border-radius: var(--radius-small); background: var(--color-surface); overflow-x: auto; line-height: 1.8; }
.prose pre code { padding: 0; border: none; color: inherit; background: none; }
.prose table { width: max-content; max-width: none; margin: 0; border-collapse: collapse; font-size: 14px; line-height: 1.85; }
.prose th, .prose td { min-width: 7.5em; padding: 11px 14px; border: 1px solid var(--color-line); text-align: left; vertical-align: top; }
.prose th { color: var(--color-ink); background: var(--color-primary-wash); font-weight: 600; }
.prose td { background: var(--color-surface); }
.table-scroll {
  display: block;
  width: 100%;
  max-width: 100%;
  min-width: 0;
  margin-block: 26px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: contain;
}
.table-scroll table { margin: 0; }
@media (max-width: 479px) {
  .prose th, .prose td { min-width: 6.5em; padding: 10px 12px; font-size: 13px; }
}
.prose hr { margin: 36px 0; border: 0; border-top: 1px solid var(--color-line); }
.prose a { overflow-wrap: anywhere; }
/* 記事本文だけ：狭い画面で表・図が横にはみ出さない */
.article-layout,
.article-body,
.prose {
  min-width: 0;
  max-width: 100%;
}
.article-body {
  overflow-x: clip;
}
.article-figure {
  margin: 28px 0 32px;
  padding: 14px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  background: var(--color-surface);
  max-width: 100%;
  min-width: 0;
}
.article-figure .figure-frame {
  display: block;
  width: 100%;
  max-width: 100%;
  min-width: 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: contain;
}
.article-figure picture {
  display: block;
  width: 100%;
  max-width: 100%;
  min-width: 0;
}
.article-figure img,
.article-figure svg {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  margin: 0 auto;
  border-radius: var(--radius-small);
  background: #F6F5F1;
}
.article-figure figcaption {
  margin-top: 12px;
  color: var(--color-muted);
  font-size: 13px;
  line-height: 1.7;
  text-align: center;
}
.figure-zoom {
  display: none;
  margin: 10px 0 0;
  text-align: center;
}
.figure-zoom a {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 8px 14px;
  border: 1px solid var(--color-line-strong);
  border-radius: var(--radius-small);
  color: var(--color-primary);
  background: var(--color-bg);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
}
.figure-zoom a:hover {
  border-color: var(--color-primary);
  background: var(--color-primary-wash);
}
/* dual zoom links: hide mobile version by default (desktop / wide) */
.figure-zoom a.figure-zoom-link--mobile { display: none; }
@media (max-width: 639px) {
  .figure-zoom {
    display: block;
    text-align: center;
    /* keep clear of fixed 上へ戻る at bottom-right */
    padding-inline: 56px;
    margin-bottom: 12px;
  }
  /* beat .figure-zoom a { display: inline-flex } specificity */
  .figure-zoom a.figure-zoom-link--desktop { display: none; }
  .figure-zoom a.figure-zoom-link--mobile { display: inline-flex; }
  .article-figure { padding: 10px; margin-inline: 0; }
  .article-figure img,
  .article-figure svg { border-radius: 6px; }
}
.article-video { margin: 32px 0; padding: 20px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); }
.article-video > h2 { margin: 0 0 12px; padding: 0; border: 0; font-size: 18px; }
.article-video .article-video-name { margin: 0 0 16px; font-size: 15px; line-height: 1.7; }
.article-video .video-embed { margin-bottom: 16px; }
.article-video > :last-child { margin-bottom: 0; }
.video-chapters, .prose .video-chapters { margin: 0; padding-left: 1.5em; font-size: 14px; }
.video-chapters li { padding-left: 0; }
.video-chapters li + li { margin-top: 2px; }
.video-chapters a { display: flex; min-height: 44px; align-items: center; gap: 12px; padding-block: 6px; line-height: 1.7; }
.video-chapter-time { flex-shrink: 0; color: var(--color-muted); font-size: 13px; font-variant-numeric: tabular-nums; white-space: nowrap; }
.article-footer { margin-top: 36px; padding: 22px 0 0; border-top: 1px solid var(--color-line); color: var(--color-muted); font-size: 13px; }
.article-footer h2 { margin-bottom: 10px; font-size: 15px; }
.article-footer p:last-child { margin-bottom: 0; }
.source-list { margin: 0 0 16px; padding-left: 20px; font-size: 13px; line-height: 1.9; }
.source-list li + li { margin-top: 10px; padding-top: 10px; border-top: 1px solid var(--color-line); }
.source-list a { display: flex; min-height: 44px; flex-direction: column; justify-content: center; padding-block: 4px; overflow-wrap: anywhere; }
.source-external { color: var(--color-muted); font-size: 12px; font-weight: 400; }
.source-url, .source-meta { color: var(--color-muted); font-size: 12px; }
.source-list .source-meta { margin: 4px 0 0; }
.article-bottom-nav { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 20px; margin-top: 28px; padding-top: 22px; border-top: 1px solid var(--color-line); }
.article-pagination { display: grid; gap: 12px; margin-top: 36px; }
.article-neighbor { display: flex; min-width: 0; min-height: 44px; flex-direction: column; gap: 6px; padding: 18px 20px; border: 1px solid var(--color-line); border-radius: var(--radius); color: var(--color-body); background: var(--color-surface); text-decoration: none; }
.article-neighbor:hover { border-color: var(--color-primary); }
.article-neighbor > span { color: var(--color-primary); font-size: 13px; font-weight: 600; }
.article-neighbor strong { font-size: 15px; }
.article-neighbor time, .related-empty { color: var(--color-muted); font-size: 13px; }
@media (min-width: 640px) { .article-pagination:has(> a + a) { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.reading-progress { position: fixed; z-index: 70; inset: 0 0 auto; height: 3px; background: var(--color-primary-soft); pointer-events: none; }
.reading-progress > span { display: block; width: 100%; height: 100%; background: #2F5D3A; transform: scaleX(0); transform-origin: left; }
.back-to-top { position: fixed; z-index: 70; right: max(16px, env(safe-area-inset-right)); bottom: max(16px, env(safe-area-inset-bottom)); display: inline-flex; min-width: 44px; min-height: 44px; align-items: center; justify-content: center; padding: 10px 16px; border: 1px solid var(--color-line-strong); border-radius: var(--radius-small); color: var(--color-primary); background: var(--color-bg); font-size: 13px; font-weight: 600; }
.back-to-top:hover { border-color: var(--color-primary); background: var(--color-primary-wash); }
.reading-progress[hidden], .back-to-top[hidden] { display: none; }

/* 読了はこの端末でだけ記録する。確認状態のバッジとは分けて表示する。 */
.read-status { display: grid; gap: 12px; margin-top: 36px; padding: 22px 20px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); }
.read-status h2 { margin-bottom: 0; font-size: 17px; }
.read-status p { margin: 0; color: var(--color-muted); font-size: 13px; }
.read-status [data-read-feedback]:empty { display: none; }
.read-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.read-status .button, .read-status .button-secondary { min-height: 44px; }
.read-reset { margin-top: 28px; padding-top: 24px; border-top: 1px solid var(--color-line); }
.read-reset .panel-note { margin-top: 10px; }
.read-reset [data-read-feedback] { margin-block: 10px 0; color: var(--color-muted); font-size: 13px; }
.read-reset [data-read-feedback]:empty { display: none; }
[data-read-end] { height: 1px; }
@media (max-width: 479px) { .read-actions > button { flex: 1 1 100%; } }

/* ---------- クイズ ---------- */
.quiz-panel, .review-panel { margin-top: 36px; padding: 24px 20px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); }
.quiz-panel h2, .review-panel h2 { margin-bottom: 14px; font-size: 19px; line-height: 1.6; }
.quiz-panel fieldset { min-width: 0; margin: 0; padding: 0; border: 0; }
.quiz-panel legend { max-width: 100%; margin-bottom: 16px; padding: 0; color: var(--color-ink); font-size: 16px; font-weight: 600; line-height: 1.85; }
.quiz-options { display: grid; gap: 10px; margin: 0 0 20px; }
.quiz-option { display: flex; min-width: 0; align-items: flex-start; gap: 12px; padding: 12px 16px; border: 1px solid var(--color-line); border-radius: 8px; color: var(--color-body); background: #FBFBF9; font-size: 14px; line-height: 1.8; cursor: pointer; transition: border-color .15s ease, background-color .15s ease; }
.quiz-option:hover { border-color: var(--color-line-strong); }
.quiz-option:has(input:checked) { border-color: var(--color-primary); color: var(--color-ink); background: var(--color-primary-wash); }
.quiz-option:has(input:focus-visible) { outline: 2px solid var(--color-primary); outline-offset: 2px; }
.quiz-option input { flex-shrink: 0; width: 16px; height: 16px; margin: 5px 0 0; accent-color: var(--color-primary); }
.quiz-option input:focus-visible { outline: none; }
.quiz-option span { min-width: 0; }
.quiz-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; }
.quiz-feedback { min-height: 76px; margin-top: 20px; padding: 16px 18px 16px 84px; border: 1px solid var(--color-line); border-radius: 8px; background: #FBFBF9 no-repeat 16px 14px / 52px 52px; font-size: 14px; line-height: 1.9; }
.quiz-feedback:empty { display: none; }
.quiz-feedback p:last-child { margin-bottom: 0; }
.quiz-feedback strong { display: block; margin-bottom: 4px; color: var(--color-ink); }
/* ケルンの表情は単体SVG（global.css と同じ /assets/ に置く。相対URLなのでファイルプレビューでも表示される） */
.quiz-result-correct { border-color: #B9D6C3; background-color: var(--color-primary-wash); background-image: url("kern-happy.svg"); }
.quiz-result-correct strong { color: var(--color-primary-dark); }
.quiz-result-incorrect { border-color: #EBC9AE; background-color: #FCF4EE; background-image: url("kern-think.svg"); }
.quiz-result-incorrect strong { color: #84492A; }

/* ---------- 確認パネル（送信しない。見た目だけクイズと揃える） ---------- */
.review-panel p { font-size: 14px; line-height: 1.9; }
.review-intro { color: var(--color-body); }
.review-summary { margin: 18px 0; padding: 14px 18px; border: 1px solid var(--color-line); border-radius: 8px; background: #FBFBF9; }
.review-summary > div + div { margin-top: 10px; }
.review-summary dt { margin-bottom: 2px; color: var(--color-muted); font-size: 12px; }
.review-summary dd { margin: 0; color: var(--color-ink); font-size: 14px; font-weight: 600; overflow-wrap: anywhere; }
.review-comment-label { display: block; color: var(--color-ink); font-size: 14px; font-weight: 600; }
.review-panel .review-help { margin-block: 6px 12px; color: var(--color-muted); font-size: 13px; overflow-wrap: anywhere; }
.review-panel textarea { display: block; width: 100%; min-height: 130px; padding: 12px 14px; border: 1px solid var(--color-line-strong); border-radius: 8px; color: var(--color-ink); background: var(--color-surface); font-size: 14px; line-height: 1.8; resize: vertical; }
.review-panel textarea:focus-visible { border-color: var(--color-primary); outline: 2px solid var(--color-primary-soft); outline-offset: 0; }
.review-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.review-actions > button { flex: 1 1 120px; }
@media (min-width: 640px) { .review-actions > button { flex: 0 0 auto; } }
.review-panel button:disabled { opacity: .5; cursor: not-allowed; }
.review-panel .review-unsaved { margin-block: 10px 0; color: #84492A; font-size: 13px; }
.review-feedback { min-height: 64px; margin: 16px 0 0; padding: 12px 14px 12px 70px; border: 1px solid #B9D6C3; border-radius: 8px; background: var(--color-primary-wash) url("kern-smile.svg") no-repeat 14px 10px / 44px 44px; overflow-wrap: anywhere; }
.review-feedback:empty { display: none; }
.review-feedback[data-review-feedback='error'] { padding-left: 14px; border-color: #E3B3A5; color: #8E3A28; background: #FBEDE8; background-image: none; }
.review-export { margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--color-line); }
.review-export h3 { margin-bottom: 6px; font-size: 15px; }
.review-downloads { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 14px; font-size: 13px; }
.review-panel [hidden] { display: none; }

/* ---------- その他のページ ---------- */
.callout { display: grid; gap: 14px; margin: 8px 0 56px; padding: 26px 24px; border: 1px solid var(--color-line); border-radius: var(--radius); background: #EFEDE6; }
.callout h2 { margin: 0; font-size: 19px; line-height: 1.7; }
.callout p { margin-bottom: 10px; font-size: 14px; line-height: 1.9; }
@media (min-width: 760px) { .callout { grid-template-columns: .8fr 1fr; align-items: center; gap: 32px; padding: 30px 32px; } }
.hub-content { max-width: 860px; padding: 26px 22px; border: 1px solid var(--color-line); border-radius: var(--radius); background: var(--color-surface); }
.hub-content > .badge { margin-bottom: 20px; }
.hub-content .prose { max-width: 100%; }
.about-content { margin-bottom: 64px; }
.not-found { max-width: 640px; min-height: 52vh; padding-block: 40px; }
.not-found .page-header { padding-top: 24px; }

/* ---------- フッター ---------- */
.site-footer { margin-top: 16px; padding: 28px 0 32px; border-top: 1px solid var(--color-line); }
.footer-inner { display: flex; flex-direction: column; gap: 18px; }
.footer-brand { color: var(--color-ink); font-size: 15px; font-weight: 700; text-decoration: none; }
.footer-tagline { margin: 4px 0 0; color: var(--color-muted); font-size: 12px; }
.footer-information { color: var(--color-muted); font-size: 12px; }
.footer-information > a { display: inline-block; margin-bottom: 6px; color: var(--color-body); font-size: 13px; }
.footer-information p { margin-bottom: 2px; }
.footer-information small { font-size: 11px; }
@media (min-width: 760px) {
  .footer-inner { flex-direction: row; align-items: flex-start; justify-content: space-between; }
  .footer-information { text-align: right; }
  .quiz-panel, .review-panel { padding: 28px 30px; }
  .hub-content { padding: 32px 34px; }
  .empty-state { padding: 28px 30px; }
  .empty-kern { width: 84px; height: 84px; }
}

@media (max-width: 400px) {
  .container { width: calc(100% - 32px); }
  .site-header { padding-inline: 16px; }
  .prose { font-size: 15px; }
  .quiz-feedback { padding-left: 18px; padding-top: 74px; background-position: 16px 14px; }
}

@media (prefers-reduced-motion: reduce) {
  :root { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}