/* ==========================================================================
   AllChinaBuy Spreadsheet — Spreadsheet Legend / Editorial Key theme
   Warm paper white · ink black-blue text · four legend keys:
   ultramarine (sheet) · vermilion (linked page) · moss (changeable) · violet (confirm)
   Signatures: key strip · crop mark · margin bracket · folio number ·
   proof underline · revision dot
   ========================================================================== */

:root {
  /* paper + ink */
  --paper:      #FBF7EC;
  --paper-2:    #F4EDDD;
  --paper-3:    #ECE3CF;
  --card:       #FFFDF7;
  --ink:        #1B2233;   /* ink black-blue body text */
  --ink-soft:   #4A5266;
  --ink-faint:  #8A8F9C;

  /* four legend keys (source & changeability — never quality/verdict) */
  --ultra:      #2E3A8C;   /* ultramarine — visible in the sheet */
  --ultra-d:    #24306E;
  --ultra-s:    #E4E7F5;
  --verm:       #C0392B;   /* vermilion — visible after opening */
  --verm-d:     #9C2D22;
  --verm-s:     #F8E3DF;
  --moss:       #4A6B3A;   /* moss green — likely to change */
  --moss-d:     #3A542E;
  --moss-s:     #E7EDDE;
  --vio:        #7A5FA8;   /* soft violet — confirm at the destination */
  --vio-d:      #624A8C;
  --vio-s:      #ECE7F5;

  --line:       #E3DAC6;
  --line-soft:  #EDE5D1;

  /* typography */
  --serif: Georgia, 'Times New Roman', Times, serif;
  --sans: system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, Consolas, monospace;

  /* geometry */
  --radius: 12px;
  --radius-sm: 8px;
  --container: 1140px;
  --shadow-sm: 0 1px 2px rgba(27, 34, 51, 0.05), 0 2px 8px rgba(27, 34, 51, 0.06);
  --shadow-md: 0 4px 14px rgba(27, 34, 51, 0.10), 0 12px 30px rgba(27, 34, 51, 0.09);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ---------- accessibility ---------- */
.skip-link { position: absolute; left: -9999px; top: 0; background: var(--ultra); color: #fff; padding: 10px 16px; z-index: 200; border-radius: 0 0 var(--radius-sm) 0; }
.skip-link:focus { left: 0; }
:focus-visible { outline: 3px solid var(--ultra); outline-offset: 2px; border-radius: 3px; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; margin: -1px; padding: 0; border: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------- layout ---------- */
.container { max-width: var(--container); margin: 0 auto; padding: 0 22px; }

/* ---------- header (light paper) ---------- */
.site-header { position: sticky; top: 0; z-index: 100; background: rgba(251, 247, 236, 0.92); backdrop-filter: saturate(120%) blur(8px); border-bottom: 1px solid var(--line); }
.header-inner { display: flex; align-items: center; gap: 20px; height: 66px; }
.brand { display: flex; align-items: center; gap: 11px; text-decoration: none; color: var(--ink); }
.brand img { width: 34px; height: 34px; display: block; border-radius: 7px; }
.brand-name { font-family: var(--serif); font-weight: 700; font-size: 1.06rem; letter-spacing: 0.01em; }
.brand-name small { display: block; font-family: var(--sans); font-weight: 600; font-size: 0.64rem; color: var(--ink-faint); letter-spacing: 0.14em; text-transform: uppercase; }

.main-nav { margin-left: auto; }
.main-nav ul { display: flex; align-items: center; gap: 2px; list-style: none; margin: 0; padding: 0; }
.main-nav a { display: block; padding: 8px 12px; text-decoration: none; color: var(--ink-soft); font-weight: 600; font-size: 0.9rem; border-radius: var(--radius-sm); }
.main-nav a:hover { background: var(--paper-2); color: var(--ink); }
.main-nav a.active { color: #fff; background: var(--ultra); }

.mobile-nav-toggle { display: none; margin-left: auto; width: 44px; height: 44px; border: 1px solid var(--line); background: var(--paper-2); border-radius: var(--radius-sm); cursor: pointer; color: var(--ink); }
.mobile-nav-toggle svg { display: block; margin: 0 auto; }

@media (max-width: 900px) {
  .main-nav { display: none; }
  .mobile-nav-toggle { display: block; }
  .main-nav.open { display: block; position: absolute; left: 0; right: 0; top: 66px; background: var(--paper-2); border-bottom: 1px solid var(--line); box-shadow: var(--shadow-md); }
  .main-nav.open ul { flex-direction: column; align-items: stretch; gap: 2px; padding: 8px; }
  .main-nav.open a { padding: 12px 14px; }
}

/* ---------- buttons ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 12px 22px; border-radius: 999px; text-decoration: none; font-weight: 700; font-size: 0.98rem; line-height: 1.2; border: 1.5px solid transparent; transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.12s ease; }
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--ultra); color: #fff; box-shadow: 0 4px 14px rgba(46, 58, 140, 0.28); }
.btn-primary:hover { background: var(--ultra-d); box-shadow: 0 6px 18px rgba(46, 58, 140, 0.36); }
.btn-secondary { background: var(--card); color: var(--ink); border-color: var(--line); box-shadow: var(--shadow-sm); }
.btn-secondary:hover { border-color: var(--ink-soft); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-ghost:hover { border-color: var(--ink-soft); background: var(--paper-2); }
.btn-sm { padding: 9px 16px; font-size: 0.88rem; }

/* ---------- hero (light) ---------- */
.hero-section { padding: 52px 0 40px; position: relative; overflow: hidden; background:
  radial-gradient(circle at 88% 6%, var(--ultra-s) 0, transparent 42%),
  radial-gradient(circle at 6% 94%, var(--moss-s) 0, transparent 40%),
  radial-gradient(circle at 98% 96%, var(--vio-s) 0, transparent 34%),
  var(--paper); }
.hero-grid { display: grid; grid-template-columns: 1.02fr 0.98fr; gap: 44px; align-items: center; }
.hero-badge { display: inline-flex; align-items: center; gap: 8px; padding: 5px 13px; border-radius: 999px; background: var(--vio-s); color: var(--vio-d); font-weight: 700; font-size: 0.76rem; letter-spacing: 0.08em; text-transform: uppercase; }
.hero-badge::before { content: ""; width: 8px; height: 8px; border-radius: 50%; background: var(--vio); }
.hero-title { font-family: var(--serif); font-size: clamp(2.0rem, 4.4vw, 3.0rem); line-height: 1.12; color: var(--ink); margin: 18px 0 16px; font-weight: 700; }
.hero-title em { font-style: normal; color: var(--ultra); }
.hero-description { font-size: 1.08rem; color: var(--ink-soft); max-width: 34em; margin: 0 0 26px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.hero-legend-note { margin-top: 20px; font-family: var(--mono); font-size: 0.74rem; letter-spacing: 0.04em; color: var(--ink-faint); }
.hero-legend-note span { display: inline-block; width: 10px; height: 10px; margin-right: 5px; border-radius: 2px; vertical-align: -1px; }

/* ---------- hero editorial key ---------- */
.hero-visual { position: relative; }
.hero-key { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 20px 18px; box-shadow: var(--shadow-md); }
.hero-key .hk-head { display: flex; align-items: center; gap: 10px; padding-bottom: 12px; border-bottom: 1px solid var(--line); margin-bottom: 14px; }
.hk-head .folio { font-family: var(--mono); font-size: 0.68rem; font-weight: 800; letter-spacing: 0.12em; color: var(--ink-faint); }
.hk-head .hk-title { font-family: var(--serif); font-weight: 700; color: var(--ink); font-size: 1.02rem; }
.hk-head .hk-title { margin-right: auto; }
.revision-dot { flex: none; width: 12px; height: 12px; border-radius: 50%; background: var(--verm); box-shadow: 0 0 0 3px var(--verm-s); }
.hk-strips { display: flex; flex-direction: column; gap: 9px; }
.hk-strip { display: flex; align-items: center; gap: 10px; }
.hk-swatch { flex: none; height: 26px; border-radius: 4px; }
.hk-swatch.w-sheet   { width: 100%;  background: var(--ultra); }
.hk-swatch.w-linked  { width: 78%;   background: var(--verm); }
.hk-swatch.w-change  { width: 60%;   background: var(--moss); }
.hk-swatch.w-confirm { width: 44%;   background: var(--vio); }
.hk-label { flex: none; font-family: var(--mono); font-size: 0.72rem; font-weight: 800; letter-spacing: 0.05em; text-transform: uppercase; color: var(--ink); }
.hk-note { font-size: 0.78rem; color: var(--ink-faint); }
.hk-proof { margin-top: 14px; padding-top: 11px; border-top: 1px dashed var(--line); }
.proof-underline { border-bottom: 3px solid var(--verm); padding-bottom: 2px; }
.hk-proof-text { font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.03em; color: var(--ink-faint); }

/* crop marks (hero key) */
.crop { position: absolute; width: 10px; height: 10px; border: 1.5px solid var(--ink-faint); opacity: 0.8; }
.crop-tl { top: 6px; left: 6px; border-right: 0; border-bottom: 0; }
.crop-tr { top: 6px; right: 6px; border-left: 0; border-bottom: 0; }
.crop-bl { bottom: 6px; left: 6px; border-right: 0; border-top: 0; }
.crop-br { bottom: 6px; right: 6px; border-left: 0; border-top: 0; }

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 26px; }
  .hero-section { padding-top: 34px; }
  .hk-swatch.w-sheet { width: 100%; }
}

/* ---------- section scaffolding ---------- */
.section { padding: 46px 0; }
.section-alt { background: var(--paper-2); }
.section-header { max-width: 700px; margin: 0 auto 34px; text-align: center; }
.eyebrow { display: inline-block; font-size: 0.76rem; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase; color: var(--vio-d); }
.section-title { font-family: var(--serif); font-size: clamp(1.6rem, 3.4vw, 2.15rem); color: var(--ink); margin: 10px 0 12px; line-height: 1.2; }
.section-lead { color: var(--ink-soft); font-size: 1.02rem; margin: 0; }

/* ---------- category grid (index-book tabs) ---------- */
.categories-section { padding-top: 10px; }
.cat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.cat-card {
  position: relative; display: flex; flex-direction: column; gap: 8px;
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 15px 15px 14px; text-decoration: none; color: var(--ink);
  box-shadow: var(--shadow-sm); transition: transform 0.14s ease, box-shadow 0.14s ease, border-color 0.14s ease;
}
.cat-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--ink-faint); }
.cat-top { display: flex; align-items: center; gap: 9px; }
.folio { font-family: var(--mono); font-size: 0.7rem; font-weight: 800; letter-spacing: 0.06em; color: var(--ink-faint); }
.cat-stripe { flex: 1; height: 5px; border-radius: 3px; }
.cat-stripe.c1 { background: var(--ultra); }
.cat-stripe.c2 { background: var(--verm); }
.cat-stripe.c3 { background: var(--moss); }
.cat-stripe.c4 { background: var(--vio); }
.cat-icon { width: 28px; height: 28px; color: var(--ink); }
.cat-icon svg { width: 100%; height: 100%; }
.cat-name { font-weight: 700; color: var(--ink); font-size: 0.95rem; line-height: 1.3; }
.cat-card .cat-arrow { margin-top: auto; font-size: 0.8rem; font-weight: 700; color: var(--ultra-d); }
/* crop marks (diagonal) */
.cat-card::before, .cat-card::after { content: ""; position: absolute; width: 8px; height: 8px; border: 1.5px solid var(--ink-faint); opacity: 0.65; pointer-events: none; }
.cat-card::before { top: 5px; left: 5px; border-right: 0; border-bottom: 0; }
.cat-card::after { bottom: 5px; right: 5px; border-left: 0; border-top: 0; }

@media (max-width: 900px) {
  .cat-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
  .cat-card { padding: 13px 13px 12px; }
}

/* ---------- legend cards (four keys) ---------- */
.legend-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.legend-card { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 18px 16px; box-shadow: var(--shadow-sm); overflow: hidden; }
.legend-card .key-strip { position: absolute; left: 0; top: 0; bottom: 0; width: 5px; }
.legend-card.k-sheet   .key-strip { background: var(--ultra); }
.legend-card.k-linked  .key-strip { background: var(--verm); }
.legend-card.k-change  .key-strip { background: var(--moss); }
.legend-card.k-confirm .key-strip { background: var(--vio); }
.legend-tag { display: inline-block; font-family: var(--mono); font-size: 0.66rem; font-weight: 800; letter-spacing: 0.1em; text-transform: uppercase; padding: 3px 8px; border-radius: 5px; margin-bottom: 10px; }
.k-sheet .legend-tag   { background: var(--ultra-s); color: var(--ultra-d); }
.k-linked .legend-tag  { background: var(--verm-s); color: var(--verm-d); }
.k-change .legend-tag  { background: var(--moss-s); color: var(--moss-d); }
.k-confirm .legend-tag { background: var(--vio-s); color: var(--vio-d); }
.legend-card h3 { font-family: var(--serif); font-size: 1.12rem; color: var(--ink); margin: 0 0 8px; line-height: 1.25; }
.legend-card p { color: var(--ink-soft); font-size: 0.9rem; margin: 0; }
@media (max-width: 900px) { .legend-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .legend-grid { grid-template-columns: 1fr; } }

/* ---------- row reading sequence (proof sheet) ---------- */
.reading-seq { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; counter-reset: rs; }
.rs-step { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 18px 16px; box-shadow: var(--shadow-sm); }
.rs-step::before { counter-increment: rs; content: "step " counter(rs); font-family: var(--mono); font-size: 0.66rem; font-weight: 800; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-faint); }
.rs-step h3 { font-family: var(--serif); font-size: 1.08rem; color: var(--ink); margin: 8px 0 8px; }
.rs-step p { color: var(--ink-soft); font-size: 0.9rem; margin: 0; }
.rs-step .rs-mark { position: absolute; top: 12px; right: 12px; width: 10px; height: 10px; border-radius: 50%; border: 2px solid var(--ink-faint); }
@media (max-width: 900px) { .reading-seq { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 520px) { .reading-seq { grid-template-columns: 1fr; } }

/* ---------- labels are not proof (duo + bracket) ---------- */
.duo-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.duo-col { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 22px; }
.duo-col h3 { margin: 0 0 10px; font-size: 1.02rem; display: flex; align-items: center; gap: 9px; color: var(--ink); }
.duo-col ul { margin: 0; padding-left: 18px; color: var(--ink-soft); font-size: 0.94rem; }
.duo-col ul li { margin: 6px 0; }
.duo-col .mark { flex: none; width: 22px; height: 22px; border-radius: 5px; display: grid; place-items: center; font-size: 0.78rem; color: #fff; font-family: var(--mono); }
.duo-col.is-a .mark { background: var(--moss); }
.duo-col.is-b .mark { background: var(--verm); }

/* margin bracket */
.margin-bracket { position: relative; max-width: 680px; margin: 0 auto; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 20px 18px 34px; box-shadow: var(--shadow-sm); }
.margin-bracket::before { content: "["; position: absolute; left: 12px; top: 50%; transform: translateY(-50%); font-family: var(--serif); font-size: 2.4rem; line-height: 1; color: var(--ultra); font-weight: 400; }
.margin-bracket .mb-label { display: block; font-family: var(--mono); font-size: 0.66rem; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ultra-d); margin-bottom: 4px; }
.margin-bracket p { margin: 0; color: var(--ink-soft); font-size: 0.94rem; }
@media (max-width: 720px) { .duo-grid { grid-template-columns: 1fr; } }

/* ---------- changeable detail rail ---------- */
.rail-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.rail-card { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px 18px 15px; box-shadow: var(--shadow-sm); }
.rail-card .rail-key { position: absolute; left: 0; top: 0; bottom: 0; width: 5px; background: var(--moss); border-radius: var(--radius) 0 0 var(--radius); }
.rail-card h3 { font-family: var(--serif); font-size: 1.05rem; color: var(--ink); margin: 0 0 6px; display: flex; align-items: center; gap: 8px; }
.rail-card h3 .dot { flex: none; width: 8px; height: 8px; border-radius: 50%; background: var(--moss); }
.rail-card p { color: var(--ink-soft); font-size: 0.88rem; margin: 0; }
.rail-note { text-align: center; color: var(--ink-faint); font-size: 0.86rem; margin: 22px 0 0; }
@media (max-width: 900px) { .rail-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .rail-grid { grid-template-columns: 1fr; } }

/* ---------- guide entry cards ---------- */
.guide-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.guide-card { display: flex; flex-direction: column; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px 22px; text-decoration: none; color: var(--ink); box-shadow: var(--shadow-sm); transition: transform 0.14s ease, box-shadow 0.14s ease; }
.guide-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.guide-card .guide-num { font-family: var(--mono); font-size: 0.78rem; color: var(--ultra-d); letter-spacing: 0.1em; }
.guide-card h3 { font-family: var(--serif); font-size: 1.24rem; color: var(--ink); margin: 8px 0 10px; }
.guide-card p { color: var(--ink-soft); font-size: 0.95rem; margin: 0 0 16px; }
.guide-card .guide-cta { margin-top: auto; font-weight: 700; color: var(--ultra-d); font-size: 0.9rem; }
@media (max-width: 900px) { .guide-grid { grid-template-columns: 1fr; } }

/* ---------- re-read at the destination (stop rules) ---------- */
.log-list { list-style: none; margin: 0; padding: 0; max-width: 760px; margin-inline: auto; }
.log-list li { display: flex; gap: 14px; align-items: flex-start; padding: 14px 16px; margin: 10px 0; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow-sm); }
.log-list .log-flag { flex: none; width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center; color: #fff; font-weight: 800; font-size: 0.8rem; font-family: var(--mono); background: var(--vio); }
.log-list p { margin: 0; color: var(--ink-soft); font-size: 0.96rem; }
.log-list strong { color: var(--ink); }

.open-note { display: inline-flex; align-items: center; gap: 9px; padding: 10px 14px; border: 1px dashed var(--verm); border-radius: var(--radius-sm); background: var(--verm-s); color: var(--verm-d); font-weight: 600; font-size: 0.92rem; margin: 10px 0; }
.open-note .qmark { flex: none; width: 24px; height: 24px; border-radius: 50%; background: var(--verm); color: #fff; display: grid; place-items: center; font-weight: 800; }

.example-flag { display: inline-block; margin-top: 14px; font-size: 0.74rem; color: var(--ink-faint); font-style: italic; border-top: 1px dashed var(--line); padding-top: 8px; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 760px; margin: 0 auto; }
details.faq-item { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); margin: 10px 0; box-shadow: var(--shadow-sm); overflow: hidden; }
details.faq-item summary { cursor: pointer; list-style: none; padding: 16px 20px; font-weight: 700; color: var(--ink); display: flex; align-items: center; justify-content: space-between; gap: 14px; }
details.faq-item summary::-webkit-details-marker { display: none; }
details.faq-item summary::after { content: "+"; font-size: 1.5rem; font-weight: 400; color: var(--ultra-d); line-height: 1; }
details.faq-item[open] summary::after { content: "–"; }
.faq-item .faq-body { padding: 0 20px 18px; color: var(--ink-soft); font-size: 0.96rem; }
.faq-item .faq-body p { margin: 0 0 10px; }

/* ---------- final CTA (ink panel) ---------- */
.final-cta { background: var(--ink); color: #fff; border-radius: 18px; padding: 44px 40px; text-align: center; position: relative; overflow: hidden; }
.final-cta::before { content: ""; position: absolute; inset: 0; opacity: 0.4; background:
  radial-gradient(circle at 12% 18%, var(--ultra) 0, transparent 42%),
  radial-gradient(circle at 88% 82%, var(--vio) 0, transparent 42%),
  radial-gradient(circle at 80% 12%, var(--verm) 0, transparent 30%); }
.final-cta h2 { font-family: var(--serif); font-size: clamp(1.5rem, 3.2vw, 2.1rem); margin: 0 0 12px; position: relative; }
.final-cta p { color: rgba(255,255,255,0.82); max-width: 32em; margin: 0 auto 24px; position: relative; }
.final-cta .btn-primary { position: relative; background: var(--ultra); }

/* ---------- footer (ink) ---------- */
.site-footer { background: var(--ink); color: rgba(255,255,255,0.74); padding: 44px 0 30px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 30px; }
.footer-brand p { color: rgba(255,255,255,0.66); font-size: 0.92rem; max-width: 34em; }
.footer-brand .brand { color: #fff; }
.footer-brand .brand-name small { color: rgba(255,255,255,0.46); }
.footer-col h4 { font-size: 0.78rem; letter-spacing: 0.12em; text-transform: uppercase; color: rgba(255,255,255,0.46); margin: 0 0 12px; }
.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col a { color: rgba(255,255,255,0.74); text-decoration: none; font-size: 0.94rem; line-height: 2.1; }
.footer-col a:hover { color: #fff; }
.footer-bottom { margin-top: 28px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,0.14); font-size: 0.82rem; color: rgba(255,255,255,0.46); display: flex; flex-wrap: wrap; gap: 8px 20px; justify-content: space-between; }
.footer-bottom .legend-swatch-row { display: inline-flex; gap: 6px; align-items: center; }
.footer-bottom .legend-swatch-row i { display: inline-block; width: 10px; height: 10px; border-radius: 2px; }
@media (max-width: 720px) { .footer-grid { grid-template-columns: 1fr; } }

/* ---------- article / guide pages ---------- */
.page-hero { background: var(--paper); border-bottom: 1px solid var(--line); padding: 46px 0 38px; position: relative; overflow: hidden; }
.page-hero .container { position: relative; }
.page-hero h1 { font-family: var(--serif); font-size: clamp(1.8rem, 4vw, 2.6rem); margin: 12px 0 12px; line-height: 1.15; color: var(--ink); }
.page-hero p { color: var(--ink-soft); max-width: 42em; font-size: 1.05rem; margin: 0; }

.article-paper { background: var(--paper); padding: 8px 0 20px; }
.article-body { max-width: 760px; margin: 0 auto; padding: 34px 22px 60px; }
.article-body h2 { font-family: var(--serif); font-size: 1.5rem; color: var(--ink); margin: 38px 0 12px; }
.article-body h3 { font-size: 1.12rem; color: var(--ink); margin: 26px 0 8px; }
.article-body p { color: var(--ink-soft); margin: 0 0 16px; }
.article-body ul, .article-body ol { color: var(--ink-soft); margin: 0 0 18px; padding-left: 22px; }
.article-body li { margin: 6px 0; }
.article-body blockquote { margin: 22px 0; padding: 16px 20px; background: var(--paper-2); border-left: 4px solid var(--ultra); border-radius: 0 var(--radius-sm) var(--radius-sm) 0; color: var(--ink-soft); font-family: var(--serif); font-size: 1.06rem; }

/* legend key row used inside article pages */
.key-list { list-style: none; margin: 0 0 20px; padding: 0; }
.key-list li { display: flex; gap: 12px; align-items: flex-start; padding: 12px 14px; margin: 8px 0; background: var(--card); border: 1px solid var(--line); border-left: 5px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow-sm); }
.key-list li.k-sheet   { border-left-color: var(--ultra); }
.key-list li.k-linked  { border-left-color: var(--verm); }
.key-list li.k-change  { border-left-color: var(--moss); }
.key-list li.k-confirm { border-left-color: var(--vio); }
.key-list li strong { color: var(--ink); }
.key-list li p { margin: 0; color: var(--ink-soft); font-size: 0.92rem; }

.back-link { display: inline-flex; align-items: center; gap: 6px; color: var(--ultra-d); font-weight: 700; text-decoration: none; font-size: 0.9rem; margin-bottom: 6px; }
.back-link:hover { text-decoration: underline; }

/* legal pages */
.legal-body { max-width: 720px; margin: 0 auto; padding: 40px 22px 60px; }
.legal-body h1 { font-family: var(--serif); color: var(--ink); font-size: 2rem; margin: 0 0 6px; }
.legal-body .legal-date { color: var(--ink-faint); font-size: 0.85rem; margin-bottom: 24px; }
.legal-body h2 { font-family: var(--serif); font-size: 1.25rem; color: var(--ink); margin: 28px 0 8px; }
.legal-body p, .legal-body li { color: var(--ink-soft); }
.legal-body ul { padding-left: 22px; }

/* 404 */
.notfound { text-align: center; padding: 70px 22px 80px; }
.notfound .big { font-family: var(--serif); font-size: clamp(4rem, 14vw, 7rem); color: var(--ink); margin: 0; line-height: 1; }
.notfound h1 { font-family: var(--serif); color: var(--ink); margin: 8px 0 12px; }
.notfound p { color: var(--ink-soft); max-width: 30em; margin: 0 auto 24px; }