/* ============================================================
   Research Portal — Shared layer
   Loaded by index.html, archive.html, and every
   research/<slug>/index.html.

   Two responsibilities:
   1. Bilingual show/hide rules (always-on, scoped to [data-lang])
   2. The floating .portal-ui capsule on research detail pages
      (back link + lang toggle)

   Home + Archive pages additionally use the Apple-style tokens
   below, but research pages keep their own design language and
   are untouched by this file beyond rules 1 and 2.
   ============================================================ */

/* --- Apple-style tokens (used by home + archive only) ---------- */
:root {
  --rp-bg: #FBFBFD;
  --rp-bg-alt: #F5F5F7;
  --rp-surface: #FFFFFF;
  --rp-ink: #1D1D1F;
  --rp-ink-soft: #424245;
  --rp-muted: #6E6E73;
  --rp-subtle: #86868B;
  --rp-rule: #D2D2D7;
  --rp-rule-soft: #E5E5E7;
  --rp-accent: #0066CC;
  --rp-accent-hover: #0077ED;

  --rp-cat-companies: #1D4E89;
  --rp-cat-industry:  #2E5B3E;
  --rp-cat-playbook:  #8C4A23;

  --rp-font-sans: "Geist", -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", system-ui, sans-serif;
  --rp-font-mono: "Geist Mono", "SF Mono", ui-monospace, monospace;
  --rp-font-zh:   "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", sans-serif;
}

/* --- Bilingual show/hide ----------------------------------------
   Supports both conventions in parallel:
     - Class:     <p class="en">...</p>   <p class="zh">...</p>
     - Attribute: <p data-lang="en">...</p>  <p data-lang="zh">...</p>
   Hide rules predicate on <html data-lang>. portal.js mirrors the
   same value onto <body data-lang> for legacy CSS compatibility. */

html[data-lang="en"] .zh,
html[data-lang="en"] [data-lang="zh"] { display: none !important; }

html[data-lang="zh"] .en,
html[data-lang="zh"] [data-lang="en"] { display: none !important; }

/* --- Floating capsule UI (research detail pages) --------------- */

.portal-ui {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 9999;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 5px 8px;
  background: rgba(251, 251, 253, 0.78);
  border: 1px solid rgba(210, 210, 215, 0.6);
  border-radius: 999px;
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  font-family: var(--rp-font-sans);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.01em;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.04);
  opacity: 0.7;
  transition: opacity 0.2s ease, transform 0.2s ease;
}
.portal-ui:hover { opacity: 1; }

.portal-ui .portal-back {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  text-decoration: none;
  color: var(--rp-ink-soft);
  padding: 4px 10px;
  border-radius: 999px;
  transition: background 0.15s ease, color 0.15s ease;
  white-space: nowrap;
}
.portal-ui .portal-back:hover {
  background: rgba(0, 0, 0, 0.05);
  color: var(--rp-ink);
}
.portal-ui .portal-back .back-arrow {
  font-size: 13px;
  line-height: 1;
  display: inline-block;
  transition: transform 0.15s ease;
}
.portal-ui .portal-back:hover .back-arrow {
  transform: translateX(-2px);
}

.portal-ui .portal-divider {
  width: 1px;
  height: 12px;
  background: rgba(0, 0, 0, 0.12);
  margin: 0 2px;
}

.portal-ui .lang-switch {
  display: inline-flex;
  gap: 1px;
}
.portal-ui .lang-btn {
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 4px 9px;
  font-family: inherit;
  font-size: 12px;
  font-weight: 500;
  color: var(--rp-muted);
  border-radius: 999px;
  letter-spacing: 0.02em;
  transition: all 0.15s ease;
  font-variant-numeric: tabular-nums;
}
.portal-ui .lang-btn:hover { color: var(--rp-ink); }
.portal-ui .lang-btn.active {
  background: var(--rp-ink);
  color: #fff;
}

/* Dark-mode adaptation: research pages with dark hero can opt in
   by adding class .portal-ui-dark on <html>. */
html.portal-ui-dark .portal-ui {
  background: rgba(20, 20, 22, 0.72);
  border-color: rgba(255, 255, 255, 0.12);
}
html.portal-ui-dark .portal-ui .portal-back { color: #d2d2d7; }
html.portal-ui-dark .portal-ui .portal-back:hover {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
}
html.portal-ui-dark .portal-ui .portal-divider { background: rgba(255,255,255,0.15); }
html.portal-ui-dark .portal-ui .lang-btn { color: #a1a1a6; }
html.portal-ui-dark .portal-ui .lang-btn:hover { color: #fff; }
html.portal-ui-dark .portal-ui .lang-btn.active {
  background: #fff;
  color: #1D1D1F;
}

/* Hide the capsule on pages with their own top nav (home/archive) */
html[data-portal-page="home"] .portal-ui,
html[data-portal-page="archive"] .portal-ui { display: none !important; }

@media (max-width: 600px) {
  .portal-ui { top: 10px; right: 10px; padding: 4px 6px; font-size: 11px; }
  .portal-ui .portal-back { padding: 3px 8px; }
  .portal-ui .lang-btn { padding: 3px 7px; font-size: 11px; }
}

@media print {
  .portal-ui { display: none !important; }
}
