/* ════════════════════════════════════════════════════════════════
   ADI / IYKYDK — 共用設計系統（單一真實來源）
   被 index.html（首頁 hub）與 r/<slug>/index.html（文章）共同 <link>。
   改這裡 → 全站頁首／頁尾／格式／底色同步。最小字級一律 ≥ 11px(0.7rem)。
   ════════════════════════════════════════════════════════════════ */

:root {
  --base:      #0D0D0D;
  --surface:   #161616;
  --surface-2: #1F1F1F;
  --border:    #2E2E2E;
  --border-lt: #3A3A3A;
  --text-1:    #E8E4DC;
  --text-2:    #A0998E;
  --text-3:    #5C5650;
  --accent:    #C0392B;
  --silver:    #BCBCBC;
  --silver-d:  #787878;

  --serif: 'Noto Serif TC', Georgia, serif;
  --sans:  'Noto Sans TC', 'Helvetica Neue', sans-serif;
  --mono:  'IBM Plex Mono', 'Courier New', monospace;

  --pad-x: clamp(1.5rem, 5vw, 4rem);
  --indent: clamp(0rem, 6vw, 7rem);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  background: var(--base);
  color: var(--text-1);
  font-family: var(--sans);
  font-weight: 300;
  -webkit-font-smoothing: antialiased;
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
::selection { background: rgba(192,57,43,0.85); color: var(--text-1); }
:focus-visible { outline: 1px solid var(--accent); outline-offset: 3px; }

.wrap { max-width: 1180px; margin: 0 auto; padding: 0 var(--pad-x); }

/* mono eyebrow（亦作 section 標題 h2） */
.eyebrow {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-2);
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
}
.eyebrow::after {
  content: '';
  display: inline-block;
  width: clamp(2rem, 14vw, 9rem);
  height: 1px;
  background: var(--border);
}

/* ───────────────── 共用 NAV（頁首）───────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background 0.35s ease, border-color 0.35s ease;
}
.nav.scrolled {
  background: rgba(13,13,13,0.94);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav__inner {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 var(--pad-x);
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}
.brand { display: flex; align-items: baseline; gap: 0.6rem; min-width: 0; }
.brand__mark {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.2rem;
  letter-spacing: 0.04em;
  color: var(--text-1);
}
.brand__x {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  color: var(--text-2);
  white-space: nowrap;
}
.brand__by {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--text-3);
  white-space: nowrap;
}
.brand__by-tablet { display: none; }
@media (min-width: 768px) { .brand__by-tablet { display: inline; } }

.menu { display: flex; align-items: center; gap: clamp(1rem, 2.4vw, 2.2rem); }
.menu a {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-2);
  transition: color 0.2s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  white-space: nowrap;
}
.menu a:hover { color: var(--text-1); }
.menu a[aria-current="page"] { color: var(--text-1); }
/* RED #1 — 導覽當前版位指示 tick */
.menu a[aria-current="page"]::before {
  content: '';
  width: 2px;
  height: 0.85em;
  background: var(--accent);
  display: inline-block;
}
.menu .zh { color: inherit; }
.menu .en { color: var(--text-3); font-size: 0.7rem; }
.menu a:hover .en, .menu a[aria-current="page"] .en { color: var(--text-2); }

/* ───────────────── 共用 FOOTER（頁尾 / REGISTRY）───────────────── */
.footer { border-top: 1px solid var(--border); padding: 4rem 0 5rem; margin-top: 0; }
.footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2.5rem 3rem;
}
.footer__brand .name { font-family: var(--serif); font-weight: 600; font-size: 1.05rem; color: var(--text-1); letter-spacing: 0.04em; }
.footer__brand .by { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.05em; color: var(--text-2); margin-top: 0.6rem; line-height: 1.7; }
.footer__col h3 {
  font-family: var(--mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-2);
  margin-bottom: 1rem;
}
.footer__col a, .footer__col p {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.03em;
  color: var(--text-2);
  display: block;
  line-height: 2;
  transition: color 0.2s ease;
}
.footer__col a:hover { color: var(--text-1); }
.footer__legal {
  margin-top: 3.5rem;
  padding-top: 1.75rem;
  border-top: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--text-2);
  line-height: 1.9;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem 2rem;
}

/* ───────────────── 動效（唯一允許：單步 fade-in）───────────────── */
.reveal { opacity: 0; transform: translateY(8px); }
.reveal.in { opacity: 1; transform: none; transition: opacity 0.45s ease, transform 0.45s ease; }

/* ════════════════════════════════════════════════════════════════
   首頁 HUB 專用區塊（hero / position / index / method）
   ════════════════════════════════════════════════════════════════ */
.section { padding: clamp(4.5rem, 9vw, 7.5rem) 0; border-bottom: 1px solid var(--border); }

.hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  padding: 8rem 0 5rem;
  border-bottom: 1px solid var(--border);
}
.hero__inner { padding-left: var(--indent); max-width: 880px; }
.hero__no { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.14em; color: var(--text-2); display: block; margin-bottom: 2.5rem; }
/* RED #2 — HERO kicker */
.hero__kicker { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--accent); display: block; margin-bottom: 1.5rem; }
.hero__rule { width: 100%; height: 1px; background: var(--border); margin-bottom: 2rem; }
.hero__title {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(1.85rem, 4.4vw, 2.85rem);
  line-height: 1.22; letter-spacing: 0.01em; color: var(--text-1);
  margin-bottom: 1.75rem; max-width: 16em;
}
.hero__dek { font-family: var(--serif); font-weight: 400; font-size: clamp(0.98rem, 1.4vw, 1.12rem); line-height: 1.75; color: var(--text-2); max-width: 40em; margin-bottom: 2rem; }
.hero__meta { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.06em; color: var(--text-2); padding-top: 1.5rem; border-top: 1px solid var(--border); margin-bottom: 2rem; display: inline-block; }
.readlink { font-family: var(--sans); font-weight: 400; font-size: 0.92rem; letter-spacing: 0.04em; color: var(--text-1); display: inline-flex; align-items: center; gap: 0.6rem; }
.readlink[hidden] { display: none; }
.readlink .arrow { font-family: var(--mono); transition: transform 0.25s ease; display: inline-block; }
.readlink:hover .arrow { transform: translateX(4px); }
.gatehint { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.08em; color: var(--text-3); display: inline-block; margin-left: 1.1rem; vertical-align: middle; }
.gatehint[hidden] { display: none; }

.position__inner { padding-left: var(--indent); }
.position__statement { font-family: var(--serif); font-weight: 400; font-size: clamp(1.3rem, 2.6vw, 1.85rem); line-height: 1.55; color: var(--text-1); max-width: 24em; margin-top: 2.25rem; }
.position__statement .dim { color: var(--text-2); }

.index__head { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; margin-bottom: 3rem; }
.index__count { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.1em; color: var(--text-2); }
.filters { display: none; gap: 1.5rem; margin-bottom: 2rem; flex-wrap: wrap; }
.filters.show { display: flex; }
.filters span { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--text-3); }

.ledger { display: flex; flex-direction: column; }
.row { display: grid; grid-template-columns: 130px 1fr 230px; gap: 0 2.5rem; padding: 2.25rem 0; border-bottom: 1px solid var(--border); align-items: start; transition: background 0.2s ease; }
.row:first-child { border-top: 1px solid var(--border); }
.row:hover { background: var(--surface); }
.row__index { font-family: var(--mono); font-size: 0.74rem; letter-spacing: 0.04em; color: var(--text-2); line-height: 1.6; padding-top: 0.35rem; }
.row__index .date { display: block; color: var(--text-2); }
.row__main { min-width: 0; }
/* RED #3 — 最新/精選標示 */
.row__flag { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.16em; color: var(--accent); display: inline-block; margin-bottom: 0.7rem; }
.row__title { font-family: var(--serif); font-weight: 400; font-size: clamp(1.1rem, 1.8vw, 1.35rem); line-height: 1.35; color: var(--text-1); margin-bottom: 0.7rem; transition: color 0.2s ease; display: inline-flex; align-items: baseline; gap: 0.7rem; }
.row__title .arrow { font-family: var(--mono); font-size: 0.85rem; color: var(--text-1); opacity: 0; transform: translateX(-4px); transition: opacity 0.2s ease, transform 0.25s ease; }
.row:hover .row__title .arrow { opacity: 1; transform: translateX(0); }
.row__dek { font-family: var(--sans); font-weight: 300; font-size: 0.9rem; line-height: 1.75; color: var(--text-2); max-width: 46em; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.row__meta { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.07em; color: var(--text-2); line-height: 1.9; padding-top: 0.35rem; text-align: right; }
.row__meta .type { color: var(--silver); display: block; }
.row__meta .tick { color: var(--text-3); }
.row__meta .gate { color: var(--text-3); }
.row--placeholder { pointer-events: none; }
.row--placeholder:hover { background: transparent; }
.row--placeholder .row__index, .row--placeholder .row__title, .row--placeholder .row__meta { color: var(--text-3); }

.method__grid { display: grid; grid-template-columns: 1fr 1.9fr; gap: 0 5rem; align-items: start; margin-top: 2.5rem; }
.method__lead { font-family: var(--serif); font-weight: 400; font-size: 1.3rem; line-height: 1.5; color: var(--text-1); }
.method__lead .accent-line { width: 2rem; height: 1px; background: var(--border-lt); margin: 1.25rem 0 0; }
.mrow { display: grid; grid-template-columns: 150px 1fr; gap: 0 2.5rem; padding: 1.4rem 0; border-bottom: 1px solid var(--border); }
.mrow:first-child { border-top: 1px solid var(--border); }
.mrow:last-child { border-bottom: none; }
.mrow__key { font-family: var(--mono); font-size: 0.74rem; letter-spacing: 0.06em; color: var(--silver); padding-top: 0.15rem; }
.mrow__val { font-size: 0.88rem; color: var(--text-2); line-height: 1.8; }

/* ════════════════════════════════════════════════════════════════
   文章頁專用：.doc 長文格式（標準化排版）
   每篇文章 <article class="doc"> 即自動套用一致的字體階層與底色。
   ════════════════════════════════════════════════════════════════ */
.doc { padding: 7.5rem 0 5rem; }
.doc__col { max-width: 760px; margin-left: var(--indent); }

.doc__back { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text-2); display: inline-flex; align-items: center; gap: 0.5rem; margin-bottom: 3rem; transition: color 0.2s ease; }
.doc__back:hover { color: var(--text-1); }
.doc__back .arrow { font-family: var(--mono); transition: transform 0.25s ease; }
.doc__back:hover .arrow { transform: translateX(-4px); }

/* RED（文章頁）— kicker 為該頁唯一識別紅 */
.doc__kicker { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--accent); display: block; margin-bottom: 1.4rem; }
.doc__title { font-family: var(--serif); font-weight: 700; font-size: clamp(1.8rem, 4vw, 2.6rem); line-height: 1.25; color: var(--text-1); margin-bottom: 1.5rem; }
.doc__standfirst { font-family: var(--serif); font-weight: 400; font-size: clamp(1.05rem, 1.6vw, 1.2rem); line-height: 1.7; color: var(--text-2); margin-bottom: 1.75rem; }
.doc__meta { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.06em; color: var(--text-2); padding: 1.25rem 0; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); margin-bottom: 3.5rem; display: flex; flex-wrap: wrap; gap: 0.4rem 1.2rem; }
.doc__meta .tick { color: var(--text-3); }

/* 內文流（prose）*/
.doc__body { color: var(--text-2); }
.doc__body > * + * { margin-top: 1.5rem; }
.doc__body h2 { font-family: var(--serif); font-weight: 700; font-size: clamp(1.35rem, 2.4vw, 1.7rem); line-height: 1.3; color: var(--text-1); margin-top: 3.5rem; padding-top: 2rem; border-top: 1px solid var(--border); }
.doc__body h2 .seq { font-family: var(--mono); font-size: 0.7rem; font-weight: 500; letter-spacing: 0.12em; color: var(--text-2); display: block; margin-bottom: 1rem; } /* 章節序號中性色，識別紅全頁僅留給 kicker（≤3 規則）*/
.doc__body h3 { font-family: var(--serif); font-weight: 600; font-size: clamp(1.1rem, 1.8vw, 1.3rem); line-height: 1.35; color: var(--text-1); margin-top: 2.5rem; }
.doc__body p { font-family: var(--sans); font-weight: 300; font-size: 1rem; line-height: 1.95; color: var(--text-2); }
.doc__body strong { color: var(--text-1); font-weight: 500; }
.doc__body em { font-style: normal; font-family: var(--mono); color: var(--text-1); font-size: 0.95em; letter-spacing: 0.02em; } /* 行內關鍵數值 */
.doc__body a.ref { color: var(--text-1); border-bottom: 1px solid var(--border-lt); }
.doc__body a.ref:hover { border-color: var(--text-2); }
.doc__body ul, .doc__body ol { padding-left: 1.4rem; color: var(--text-2); }
.doc__body li { font-family: var(--sans); font-weight: 300; font-size: 1rem; line-height: 1.9; margin-top: 0.5rem; }
.doc__body li::marker { color: var(--text-3); }

/* 引述 / 來源語 */
.doc__body blockquote { border-left: 2px solid var(--border-lt); padding-left: 1.5rem; font-family: var(--serif); font-size: 1.1rem; line-height: 1.7; color: var(--text-1); }
.doc__body blockquote cite { display: block; margin-top: 0.75rem; font-family: var(--mono); font-style: normal; font-size: 0.72rem; letter-spacing: 0.06em; color: var(--text-2); }

/* 圖片 + 圖說 */
.doc figure { margin: 2.75rem 0; }
.doc figure img { width: 100%; border: 1px solid var(--border); }
.doc figcaption { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.04em; color: var(--text-2); line-height: 1.7; margin-top: 0.9rem; padding-left: 1rem; border-left: 1px solid var(--border-lt); }

/* 無框比較表（方案 D） */
.spec { margin: 2.75rem 0; }
.spec__cap { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--text-2); margin-bottom: 1rem; }
.spec table { width: 100%; border-collapse: collapse; }
.spec th { font-family: var(--mono); font-weight: 500; font-size: 0.7rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--text-2); text-align: left; padding: 0 0 0.7rem; border-bottom: 1px solid var(--border-lt); }
.spec td { font-family: var(--sans); font-weight: 300; font-size: 0.95rem; color: var(--text-2); padding: 1rem 0; border-bottom: 1px solid var(--border); vertical-align: top; }
.spec td:first-child { font-family: var(--mono); font-size: 0.8rem; color: var(--silver); letter-spacing: 0.02em; }
.spec td em { font-style: normal; font-family: var(--mono); color: var(--text-1); }
.spec tr:last-child td { border-bottom: none; }

/* 來源清單 */
.doc__sources { margin-top: 4rem; padding-top: 2rem; border-top: 1px solid var(--border); }
.doc__sources h2 { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--text-2); margin-bottom: 1.5rem; border: 0; padding: 0; }
.doc__sources ol { padding-left: 1.6rem; }
.doc__sources li { font-family: var(--mono); font-size: 0.76rem; letter-spacing: 0.01em; line-height: 1.8; color: var(--text-2); margin-top: 0.7rem; }
.doc__sources a { color: var(--text-1); border-bottom: 1px solid var(--border-lt); }

/* 更正欄 */
.doc__correction { margin-top: 2.5rem; padding: 1.5rem 1.75rem; border: 1px solid var(--border); }
.doc__correction h3 { font-family: var(--mono); font-size: 0.7rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--text-2); margin: 0 0 0.75rem; }
.doc__correction p { font-family: var(--sans); font-weight: 300; font-size: 0.85rem; color: var(--text-3); line-height: 1.8; }

/* 版型示意標記（正式內文帶入後可刪） */
.doc__placeholder { margin-top: 2rem; padding: 1.25rem 1.5rem; border: 1px dashed var(--border-lt); font-family: var(--mono); font-size: 0.74rem; letter-spacing: 0.03em; color: var(--text-3); line-height: 1.8; }

/* ───────────────── RESPONSIVE ───────────────── */
@media (max-width: 1023px) {
  .method__grid { grid-template-columns: 1fr; gap: 2.5rem; }
  .row { grid-template-columns: 110px 1fr; }
  .row__meta { grid-column: 2; text-align: left; padding-top: 0.9rem; }
  .row__meta .type { display: inline; }
}
@media (max-width: 767px) {
  :root { --indent: 0rem; }
  .menu { gap: 1rem; }
  .menu a .en { display: none; }
  .nav__inner { gap: 0.75rem; }
  .brand__by { display: none; }
  .hero { min-height: 0; padding: 7rem 0 4rem; }
  .hero__no { margin-bottom: 1.5rem; }
  .gatehint { display: block; margin-left: 0; margin-top: 0.75rem; }
  .row { grid-template-columns: 1fr; gap: 0.5rem; padding: 1.9rem 0; }
  .row__index { padding-top: 0; }
  .row__index .date { display: inline; }
  .row__index .date::before { content: ' / '; }
  .row__meta { grid-column: 1; text-align: left; padding-top: 0.6rem; }
  .footer__grid { grid-template-columns: 1fr; gap: 2rem; }
  .footer__legal { flex-direction: column; }
  .doc { padding-top: 6rem; }
  .spec td:first-child { display: block; padding-bottom: 0.25rem; border: 0; }
  .spec td { padding: 0.85rem 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1 !important; transform: none !important; transition: none !important; }
  .readlink .arrow, .row__title .arrow, .doc__back .arrow { transition: none !important; }
}