/* ============================================================
   ONEPC · Atlas — shared theme + atlas styles
   Used by: index.html, landscape-*.html
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:ital,opsz,wght@0,9..144,300..600;1,9..144,300..600&family=IBM+Plex+Mono:wght@300;400;500&family=IBM+Plex+Sans:wght@300;400;500;600&display=swap');

:root {
  --paper:        #F2EFE7;
  --paper-2:      #ECE8DD;
  --paper-3:      #E5E0D2;
  --ink:          #15171A;
  --ink-2:        #6B6F75;
  --ink-3:        #A5A39A;
  --hairline:     rgba(21,23,26,0.10);
  --hairline-2:   rgba(21,23,26,0.22);
  --accent:       #C44519;
  --accent-soft:  rgba(196,69,25,0.10);
  --easy:         #1F6B4E;
  --med:          #B07300;
  --hard:         #A02A1F;

  --serif: 'Fraunces', 'Noto Serif SC', 'Songti SC', 'Times New Roman', serif;
  --sans:  'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'PingFang TC', 'Source Han Sans CN', 'Source Han Sans TC', system-ui, sans-serif;
  --mono:  'IBM Plex Mono', 'SF Mono', Menlo, monospace;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-image: radial-gradient(rgba(21,23,26,0.045) 1px, transparent 1px);
  background-size: 28px 28px;
  background-position: -1px -1px;
}

a { color: inherit; text-decoration: none; }

.paper {
  max-width: 1320px;
  margin: 0 auto;
  padding: 56px 44px 88px;
  position: relative;
}

/* ===== Top meta strip + lang switcher ===== */
.top-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--ink-2);
  text-transform: uppercase;
  margin-bottom: 36px;
  border-bottom: 1px solid var(--hairline-2);
  padding-bottom: 14px;
}
.top-meta > .meta-group { display: inline-flex; align-items: center; gap: 8px; }
.top-meta a:hover { color: var(--accent); }
.seal {
  display: inline-flex; align-items: center; justify-content: center;
  width: 18px; height: 18px; border-radius: 50%;
  border: 1.5px solid var(--ink);
  font-family: var(--serif);
  font-style: italic;
  font-size: 10px;
  line-height: 1;
  padding-top: 1px;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid var(--hairline-2);
  border-radius: 999px;
  padding: 2px;
  background: var(--paper);
}
.lang-switch button {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  background: transparent;
  border: 0;
  padding: 5px 11px;
  border-radius: 999px;
  cursor: pointer;
  color: var(--ink-2);
  transition: background 180ms, color 180ms;
  min-height: 32px;
  min-width: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
@media (max-width: 600px) {
  .lang-switch button {
    min-height: 44px;
    min-width: 44px;
    padding: 10px 14px;
    font-size: 11px;
  }
  .top-meta {
    font-size: 10px;
    gap: 10px;
    margin-bottom: 22px;
    padding-bottom: 10px;
  }
  /* On phones the "Step N of 3" indicator just duplicates the visible
     progress bar — hide it so the lang switch can breathe. (We can't
     hide the whole last meta-group because index.html uses it for the
     header CTA pill.) */
  .top-meta [data-i18n="step"] { display: none; }
}
body { -webkit-tap-highlight-color: rgba(196, 69, 25, 0.10); }
.lang-switch button:hover { color: var(--ink); }
.lang-switch button.active {
  background: var(--ink);
  color: var(--paper);
}

/* ===== Hero ===== */
.hero {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: end;
  gap: 32px;
  margin-bottom: 24px;
}
.eyebrow {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--ink-2);
  text-transform: uppercase;
  margin-bottom: 14px;
}
.eyebrow .accent-bar {
  display: inline-block; width: 20px; height: 1px;
  background: var(--accent); vertical-align: 4px; margin-right: 10px;
}
h1.title {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 350;
  font-size: clamp(72px, 11vw, 156px);
  line-height: 0.92;
  letter-spacing: -0.04em;
  margin: 0;
  font-variation-settings: "opsz" 144, "SOFT" 30;
}
h1.title .slash {
  font-style: normal;
  color: var(--accent);
  margin: 0 0.04em;
  font-weight: 300;
}
.title-cn {
  font-family: var(--sans);
  font-weight: 500;
  font-size: clamp(20px, 2.4vw, 30px);
  letter-spacing: 0.06em;
  color: var(--ink);
  margin-top: 18px;
}
.title-cn .dim {
  color: var(--ink-3);
  font-family: var(--mono);
  font-weight: 400;
  font-size: 0.6em;
  letter-spacing: 0.18em;
  margin-left: 12px;
  text-transform: uppercase;
}
.hero-side {
  text-align: right;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-2);
  letter-spacing: 0.1em;
  line-height: 1.7;
  padding-bottom: 8px;
}
.hero-side .big-num {
  display: block;
  font-family: var(--serif);
  font-style: italic;
  font-size: 64px;
  color: var(--ink);
  line-height: 1;
  letter-spacing: -0.04em;
  margin-bottom: 4px;
}
.lede {
  margin: 28px 0 0 0;
  max-width: 720px;
  font-size: 16px;
  color: var(--ink);
  line-height: 1.55;
}
.lede em {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
}

/* ===== Legend ===== */
.legend {
  margin: 36px 0 8px;
  padding: 18px 22px;
  background: var(--paper-2);
  border: 1px solid var(--hairline);
  border-radius: 2px;
  display: flex;
  flex-wrap: wrap;
  gap: 28px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink);
  letter-spacing: 0.04em;
  align-items: center;
}
.legend-title {
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--ink-2);
  text-transform: uppercase;
  margin-right: 8px;
}
.legend-item { display: inline-flex; align-items: center; gap: 8px; }
.legend-dot { width: 9px; height: 9px; border-radius: 50%; }
.legend-dot.easy { background: var(--easy); }
.legend-dot.med  { background: var(--med); }
.legend-dot.hard { background: var(--hard); }
.legend-hot {
  color: var(--accent);
  font-family: var(--serif);
  font-style: italic;
  font-weight: 500;
  font-size: 14px;
  line-height: 1;
}

/* ===== Atlas grid ===== */
.atlas {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  margin-top: 56px;
  position: relative;
}
.atlas::before {
  content: '';
  position: absolute;
  top: 0; bottom: 0;
  left: 50%;
  width: 1px;
  background: var(--hairline);
}
.column { position: relative; }

.col-head {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: end;
  column-gap: 18px;
  border-bottom: 1.5px solid var(--ink);
  padding-bottom: 16px;
  margin-bottom: 36px;
}
.col-num {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 350;
  font-size: 56px;
  line-height: 0.9;
  letter-spacing: -0.04em;
  color: var(--ink);
}
.col-title-wrap { padding-bottom: 8px; }
.col-title {
  font-family: var(--sans);
  font-weight: 500;
  font-size: 22px;
  margin: 0;
  letter-spacing: 0.02em;
}
.col-title .accent { color: var(--accent); }
.col-en {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  color: var(--ink-2);
  text-transform: uppercase;
  margin-top: 4px;
}
.col-count {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  text-transform: uppercase;
  text-align: right;
  padding-bottom: 8px;
  line-height: 1.5;
}
.col-count b {
  color: var(--ink);
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  font-size: 22px;
  letter-spacing: -0.02em;
  display: block;
}

/* Categories */
.category { margin-bottom: 36px; }
.cat-head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 8px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--hairline);
}
.cat-num {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--accent);
  font-weight: 500;
}
.cat-name {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 14px;
  margin: 0;
  letter-spacing: 0.04em;
}
.cat-en {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  font-size: 14px;
  color: var(--ink-2);
  margin-left: auto;
}

/* Track row */
.track {
  position: relative;
  display: grid;
  grid-template-columns: 14px 1fr auto 12px;
  gap: 14px;
  padding: 12px 4px 13px 8px;
  border-bottom: 1px dashed var(--hairline);
  align-items: start;
  cursor: pointer;
  transition: background 180ms ease;
}
.track::before {
  content: '';
  position: absolute;
  left: -2px; top: 8px; bottom: 8px;
  width: 2px;
  background: var(--accent);
  transform: scaleY(0);
  transition: transform 220ms cubic-bezier(.4,0,.2,1);
}
.track:hover { background: rgba(196,69,25,0.035); }
.track:hover::before { transform: scaleY(0.5); }
.track.expanded { background: rgba(196,69,25,0.05); }
.track.expanded::before { transform: scaleY(1); }
.track:last-child { border-bottom: none; }

.track-dot {
  width: 9px; height: 9px; border-radius: 50%;
  margin-top: 8px;
  box-shadow: 0 0 0 3px var(--paper), 0 0 0 4px var(--hairline);
}
.track-dot.easy { background: var(--easy); }
.track-dot.med  { background: var(--med); }
.track-dot.hard { background: var(--hard); }

.track-main { min-width: 0; }
.track-cn {
  font-family: var(--sans);
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.01em;
  color: var(--ink);
  line-height: 1.35;
}
.track-cn .hot {
  color: var(--accent);
  font-family: var(--serif);
  font-style: italic;
  font-weight: 500;
  margin-right: 6px;
  display: inline-block;
  transform: translateY(-1px);
}
.track-cn .badge {
  font-family: var(--mono);
  font-size: 9.5px;
  color: var(--ink-3);
  letter-spacing: 0.14em;
  margin-left: 8px;
  text-transform: uppercase;
  font-weight: 400;
}
.track-en {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  font-size: 13.5px;
  color: var(--ink-2);
  margin-top: 1px;
  letter-spacing: 0;
  line-height: 1.4;
}
.track-comp {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-3);
  margin-top: 6px;
  letter-spacing: 0.02em;
  line-height: 1.5;
}
.track-comp .sep { color: var(--hairline-2); margin: 0 6px; }
.track-comp a.comp-link {
  color: var(--ink-2);
  text-decoration: none;
  border-bottom: 1px dotted var(--hairline-2);
  transition: color 160ms, border-color 160ms;
}
.track-comp a.comp-link:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.track-tag {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  align-self: start;
  margin-top: 9px;
  white-space: nowrap;
  font-weight: 500;
}
.track-tag.easy { color: var(--easy); }
.track-tag.med  { color: var(--med); }
.track-tag.hard { color: var(--hard); }

.track-chev {
  width: 8px; height: 8px;
  border-right: 1.5px solid var(--ink-3);
  border-bottom: 1.5px solid var(--ink-3);
  transform: rotate(45deg);
  transition: transform 320ms cubic-bezier(.4,0,.2,1), border-color 200ms;
  margin-top: 12px;
  align-self: start;
  justify-self: end;
}
.track:hover .track-chev { border-color: var(--ink); }
.track.expanded .track-chev {
  transform: rotate(-135deg) translate(-2px, -2px);
  border-color: var(--accent);
}

/* Detail panel */
.track-detail {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 380ms cubic-bezier(.2,.85,.2,1), opacity 240ms ease;
  opacity: 0;
  margin-top: 0;
}
.track.expanded .track-detail {
  grid-template-rows: 1fr;
  opacity: 1;
  margin-top: 12px;
}
.track-detail > .td-inner { overflow: hidden; min-height: 0; }
.track-detail .td-pad {
  padding: 14px 16px 14px 18px;
  background: var(--paper-2);
  border-left: 2px solid var(--accent);
  border-radius: 1px 4px 4px 1px;
  box-shadow: inset 0 0 0 1px rgba(21,23,26,0.04);
}
.td-line {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  font-size: 14px;
  color: var(--ink);
  margin: 0 0 12px;
  line-height: 1.5;
  letter-spacing: 0.01em;
}
.td-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px 28px;
  margin: 0;
  padding-top: 10px;
  border-top: 1px solid var(--hairline);
}
.td-deepdive {
  display: inline-block;
  margin-top: 14px;
  padding: 8px 16px;
  background: var(--ink);
  color: var(--paper);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  text-decoration: none;
  font-weight: 500;
  transition: background 200ms;
}
.td-deepdive:hover { background: var(--accent); }
.td-cell { display: flex; flex-direction: column; gap: 3px; min-width: 0; }
.td-key {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.2em;
  color: var(--ink-3);
  text-transform: uppercase;
  font-weight: 500;
}
.td-val {
  font-family: var(--sans);
  font-size: 12.5px;
  color: var(--ink);
  font-weight: 500;
  line-height: 1.45;
  word-break: break-word;
}
.td-val .mono { font-family: var(--mono); font-size: 11.5px; }

/* ===== Sources block (bibliography at bottom of each atlas) ===== */
.sources-block {
  margin: 80px 0 32px;
  padding: 40px 0 32px;
  border-top: 1.5px solid var(--ink);
}
.contact-block {
  margin: 0 0 64px;
  padding: 28px 32px;
  background: var(--paper-2);
  border: 1px solid var(--hairline);
  border-radius: 6px;
}
.contact-eyebrow {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 8px;
}
.contact-lede {
  font-size: 15px;
  color: var(--ink-2);
  line-height: 1.55;
  margin: 0 0 12px;
  max-width: 640px;
}
.contact-email {
  display: inline-block;
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-underline-offset: 4px;
}
.contact-email:hover { color: var(--accent); }
.sources-eyebrow {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 500;
  margin-bottom: 10px;
}
.sources-title {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  font-size: 32px;
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}
.sources-lede {
  font-size: 15px;
  color: var(--ink-2);
  margin: 0 0 24px;
  max-width: 720px;
  line-height: 1.55;
}
.sources-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
  border-top: 1px solid var(--hairline);
}
.source-link {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 13px 16px;
  border-bottom: 1px dashed var(--hairline);
  text-decoration: none;
  color: var(--ink);
  transition: background 180ms, color 180ms, padding-left 220ms;
  font-family: var(--sans);
  font-size: 13.5px;
}
.source-link:nth-child(odd) { border-right: 1px dashed var(--hairline); }
.source-link:hover {
  background: rgba(196,69,25,0.04);
  color: var(--accent);
  padding-left: 22px;
}
.source-link .source-label { letter-spacing: 0.005em; }
.source-link .source-arrow {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--ink-3);
  margin-left: 12px;
  flex-shrink: 0;
  transition: transform 200ms, color 180ms;
}
.source-link:hover .source-arrow { color: var(--accent); transform: translate(2px, -2px); }
@media (max-width: 720px) {
  .sources-grid { grid-template-columns: 1fr; }
  .source-link:nth-child(odd) { border-right: none; }
}

/* Footer */
.footer {
  margin-top: 64px;
  padding-top: 22px;
  border-top: 1.5px solid var(--ink);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--ink-2);
  text-transform: uppercase;
}
.footer .signature {
  font-family: var(--serif);
  font-style: italic;
  font-size: 14px;
  color: var(--ink);
  text-transform: none;
  letter-spacing: 0;
}

/* Animations */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
.hero, .legend, .atlas, .footer {
  animation: fadeUp 600ms ease-out both;
}
.legend { animation-delay: 80ms; }
.atlas  { animation-delay: 160ms; }
.footer { animation-delay: 240ms; }

/* English mode adjustments */
html.lang-en .track-cn,
html.lang-en .col-title,
html.lang-en .cat-name {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
}
html.lang-en .cat-en,
html.lang-en .col-en,
html.lang-en .track-en {
  font-family: var(--sans);
  font-style: normal;
  font-weight: 400;
  text-transform: none;
  font-size: 11px;
  color: var(--ink-3);
  letter-spacing: 0.02em;
}

/* ===== Inline atlas → quiz CTA (always visible, between lede and legend) ===== */
.atlas-quiz-cta {
  margin: 28px 0 8px;
  padding: 22px 26px;
  background: var(--ink);
  color: var(--paper);
  border-radius: 4px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}
.atlas-quiz-cta .aqc-eyebrow {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 4px;
}
.atlas-quiz-cta .aqc-title {
  font-family: var(--serif);
  font-style: italic;
  font-size: 18px;
  letter-spacing: 0.005em;
  line-height: 1.4;
  color: var(--paper);
}
.atlas-quiz-cta .aqc-btn {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  background: var(--accent);
  color: var(--paper);
  padding: 12px 20px;
  border-radius: 999px;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  transition: background 200ms, transform 200ms;
}
.atlas-quiz-cta .aqc-btn:hover { background: #d65028; transform: translateX(2px); }
.atlas-quiz-cta .aqc-arrow { font-family: var(--serif); font-style: italic; }

/* ===== CTA Banner (fires after N atlas views) ===== */
.cta-banner {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: var(--ink);
  color: var(--paper);
  padding: 20px 22px;
  border-radius: 12px;
  max-width: 360px;
  box-shadow: 0 16px 48px rgba(0,0,0,0.20), 0 4px 12px rgba(0,0,0,0.10);
  font-family: var(--sans);
  z-index: 1000;
  opacity: 0;
  transform: translateY(24px) scale(0.96);
  transition: opacity 380ms ease, transform 460ms cubic-bezier(.2,.85,.2,1);
  pointer-events: none;
}
.cta-banner.show {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}
.cta-banner .cta-eyebrow {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}
.cta-banner .cta-title {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  font-size: 17px;
  line-height: 1.4;
  margin-bottom: 18px;
  color: var(--paper);
  letter-spacing: 0.005em;
}
.cta-banner .cta-row {
  display: flex;
  align-items: center;
  gap: 12px;
  justify-content: space-between;
}
.cta-banner .cta-btn {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  background: var(--accent);
  color: var(--paper);
  padding: 10px 16px;
  border-radius: 999px;
  font-weight: 500;
  text-decoration: none;
  transition: transform 200ms ease, background 200ms;
  display: inline-block;
}
.cta-banner .cta-btn:hover {
  transform: translateX(2px);
  background: #d65028;
}
.cta-banner .cta-dismiss {
  background: transparent;
  border: 0;
  color: var(--ink-3);
  font-size: 24px;
  line-height: 1;
  cursor: pointer;
  padding: 0 6px;
  transition: color 180ms;
}
.cta-banner .cta-dismiss:hover { color: var(--paper); }

@media (max-width: 600px) {
  .cta-banner {
    left: 16px;
    right: 16px;
    bottom: 16px;
    max-width: none;
  }
}

/* Mobile */
@media (max-width: 920px) {
  .paper { padding: 32px 20px 60px; }
  .atlas { grid-template-columns: 1fr; gap: 40px; }
  .atlas::before { display: none; }
  .hero { grid-template-columns: 1fr; }
  .hero-side { text-align: left; }
  h1.title { font-size: 64px; }
}

@media (max-width: 600px) {
  /* Atlas detail panel — single-column key/value pairs on phones */
  .td-grid { grid-template-columns: 1fr; gap: 10px 0; }
  /* Atlas-bottom quiz CTA: full-width button, tighter band */
  .atlas-quiz-cta { padding: 18px 20px; gap: 14px; flex-direction: column; align-items: flex-start; }
  .atlas-quiz-cta .aqc-btn { width: 100%; text-align: center; padding: 14px 20px; }
}

@media (max-width: 380px) {
  /* iPhone SE / very narrow — tighten home hero so "ONEPC." doesn't kiss the edge */
  h1.title { font-size: 56px; letter-spacing: -0.04em; }
}