/* Hub book reader · Field Primer / Field Research · READ not source download */
.reader-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg, #0c0c0e);
}

.reader-app {
  flex: 1;
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  min-height: 0;
}

/* ── shelf ── */
.shelf {
  padding: 20px 16px 48px;
}
.shelf-hero {
  margin: 0 0 18px;
  padding: 18px;
  border-radius: 14px;
  border: 1px solid var(--border, #2c2c36);
  background:
    radial-gradient(ellipse 70% 80% at 0% 0%, rgba(0, 255, 163, 0.08), transparent 55%),
    radial-gradient(ellipse 50% 60% at 100% 0%, rgba(0, 212, 255, 0.06), transparent 50%),
    var(--surface, #18181d);
}
.shelf-hero h2 { margin: 0 0 8px; font-size: 1.4rem; }
.shelf-hero p { margin: 0 0 10px; color: #c8c8d4; max-width: 62ch; }

.book-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}
.book-card {
  display: flex;
  flex-direction: column;
  border-radius: 14px;
  border: 1px solid var(--border, #2c2c36);
  background: var(--surface, #18181d);
  overflow: hidden;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.book-card:hover {
  border-color: rgba(0, 255, 163, 0.45);
  box-shadow: 0 0 24px rgba(0, 255, 163, 0.12);
}
.book-cover {
  aspect-ratio: 16 / 9;
  background: #0a0c0b center/cover no-repeat;
  position: relative;
}
.book-cover::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 40%, rgba(12, 12, 14, 0.92) 100%);
}
.book-card-body {
  padding: 14px 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}
.book-card h3 {
  margin: 0;
  font: 800 1.15rem system-ui;
  color: var(--text, #ececf1);
}
.book-card .sub {
  margin: 0;
  color: var(--muted, #8b8b9a);
  font-size: 13px;
  line-height: 1.45;
  flex: 1;
}
.book-card .meta {
  font: 11px var(--mono, ui-monospace, monospace);
  color: var(--dim, #5c5c6a);
}
.book-card .actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}
.book-card .btn-read {
  /* primary Read CTA — not a download glyph */
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: 10px;
  border: 1px solid rgba(0, 255, 163, 0.55);
  background: linear-gradient(180deg, #14e89a, #00c47a);
  color: #04140e !important;
  font: 800 13px system-ui;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  text-decoration: none !important;
  box-shadow: 0 0 16px rgba(0, 255, 163, 0.28);
  cursor: pointer;
}
.book-card .btn-read:hover {
  background: linear-gradient(180deg, #5dffc0, #00ffa3);
  color: #02100a !important;
  text-decoration: none !important;
}
.book-card .btn-read .ico { font-size: 15px; }

/* ── book stage ── */
.book-stage {
  display: grid;
  grid-template-columns: minmax(220px, 300px) 1fr;
  min-height: calc(100vh - 120px);
  border-top: 1px solid var(--border, #2c2c36);
}
@media (max-width: 820px) {
  .book-stage { grid-template-columns: 1fr; }
  .toc { max-height: 42vh; border-right: 0; border-bottom: 1px solid var(--border, #2c2c36); }
}

.toc {
  background: var(--bg2, #121216);
  border-right: 1px solid var(--border, #2c2c36);
  display: flex;
  flex-direction: column;
  min-height: 0;
  overflow: hidden;
}
.toc-hd {
  padding: 12px 12px 8px;
  border-bottom: 1px solid var(--border, #2c2c36);
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.toc-book {
  font: 800 14px system-ui;
  color: var(--grin, #00ffa3);
}
.toc-sub {
  font: 11px system-ui;
  color: var(--muted, #8b8b9a);
  line-height: 1.35;
}
.toc-filter-wrap { padding: 8px 12px 0; }
.toc-filter {
  width: 100%;
  box-sizing: border-box;
  padding: 7px 10px;
  border-radius: 8px;
  border: 1px solid var(--border, #2c2c36);
  background: #0a0c0b;
  color: var(--text, #ececf1);
  font: 12px system-ui;
}
.toc-filter:focus {
  outline: none;
  border-color: rgba(0, 255, 163, 0.5);
}
.toc-sections {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  padding: 8px 12px 0;
}
.sec-btn {
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--border, #2c2c36);
  background: var(--bg, #0c0c0e);
  color: var(--muted, #8b8b9a);
  font: 700 10px system-ui;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
}
.sec-btn.on, .sec-btn:hover {
  color: #06140f;
  background: linear-gradient(135deg, var(--grin, #00ffa3), var(--neon-b, #00d4ff));
  border-color: transparent;
}
.toc-list {
  flex: 1;
  overflow: auto;
  padding: 8px 8px 12px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.toc-item {
  display: block;
  width: 100%;
  text-align: left;
  padding: 8px 10px;
  border: 1px solid transparent;
  border-radius: 8px;
  background: transparent;
  color: var(--text, #ececf1);
  font: 600 12px/1.35 system-ui;
  cursor: pointer;
}
.toc-item:hover {
  background: var(--surface, #18181d);
  border-color: var(--border, #2c2c36);
}
.toc-item.on {
  background: rgba(0, 255, 163, 0.1);
  border-color: rgba(0, 255, 163, 0.4);
  color: var(--grin, #00ffa3);
}
.toc-item .n {
  display: block;
  font: 700 10px var(--mono, ui-monospace, monospace);
  color: var(--dim, #5c5c6a);
  margin-bottom: 2px;
  letter-spacing: 0.04em;
}
.toc-item.on .n { color: rgba(0, 255, 163, 0.7); }
.toc-foot {
  padding: 10px 12px;
  border-top: 1px solid var(--border, #2c2c36);
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

/* ── page ── */
.page {
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  background: var(--bg, #0c0c0e);
}
.page-toolbar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border, #2c2c36);
  background: var(--bg2, #121216);
  position: sticky;
  top: 0;
  z-index: 5;
}
.page-meta {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.page-title {
  font: 700 13px system-ui;
  color: var(--text, #ececf1);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.page-progress {
  font: 11px var(--mono, ui-monospace, monospace);
  color: var(--dim, #5c5c6a);
}
.page-body {
  flex: 1;
  overflow: auto;
  padding: 28px 22px 40px;
}
.page-empty {
  max-width: 40ch;
  margin: 48px auto;
  text-align: center;
  color: var(--muted, #8b8b9a);
}
.page-footer-nav {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  padding: 14px 18px 28px;
  border-top: 1px solid var(--border, #2c2c36);
  background: var(--bg2, #121216);
}

/* prose */
.prose {
  max-width: 48rem;
  margin: 0 auto;
  color: #e4e4ec;
  font-size: 1.05rem;
  line-height: 1.75;
}
.prose h1, .prose h2, .prose h3, .prose h4 {
  color: var(--text, #ececf1);
  line-height: 1.25;
  margin: 1.4em 0 0.55em;
}
.prose h1 {
  font-size: 1.75rem;
  margin-top: 0;
  color: var(--grin, #00ffa3);
  border-bottom: 1px solid var(--border, #2c2c36);
  padding-bottom: 0.35em;
}
.prose h2 {
  font-size: 1.35rem;
  color: var(--neon-b, #00d4ff);
}
.prose h3 { font-size: 1.12rem; color: #c8c8d4; }
.prose p { margin: 0 0 1em; }
.prose a { color: var(--neon-b, #00d4ff); }
.prose a:hover { color: var(--grin, #00ffa3); }
.prose ul, .prose ol { margin: 0 0 1em; padding-left: 1.4em; }
.prose li { margin: 0.25em 0; }
.prose blockquote {
  margin: 0 0 1em;
  padding: 0.6em 1em;
  border-left: 3px solid var(--grin, #00ffa3);
  background: rgba(0, 255, 163, 0.06);
  color: #c8c8d4;
}
.prose code {
  font-family: var(--mono, ui-monospace, monospace);
  font-size: 0.9em;
  background: #121218;
  border: 1px solid var(--border, #2c2c36);
  border-radius: 4px;
  padding: 0.1em 0.35em;
  color: #b8f0d4;
}
.prose pre {
  margin: 0 0 1.1em;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid var(--border, #2c2c36);
  background: #0a0c0b;
  overflow: auto;
  font: 13px/1.5 var(--mono, ui-monospace, monospace);
  color: #d0d0dc;
}
.prose pre code {
  background: none;
  border: 0;
  padding: 0;
  color: inherit;
}
.prose table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 1.1em;
  font-size: 0.95rem;
}
.prose th, .prose td {
  border: 1px solid var(--border, #2c2c36);
  padding: 8px 10px;
  text-align: left;
}
.prose th {
  background: var(--surface, #18181d);
  color: var(--grin, #00ffa3);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.prose img {
  max-width: 100%;
  height: auto;
  border-radius: 10px;
  border: 1px solid var(--border, #2c2c36);
  margin: 0.5em 0 1em;
  display: block;
}
.prose figure.fig {
  margin: 0 0 1.25em;
  padding: 0;
}
.prose figure.fig img {
  width: 100%;
  max-width: 52rem;
  margin: 0 auto;
  background: #0a0c0b;
}
.prose hr {
  border: 0;
  border-top: 1px solid var(--border, #2c2c36);
  margin: 1.6em 0;
}
.prose .eyebrow {
  font: 700 11px system-ui;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--grin, #00ffa3);
  margin: 0 0 0.75em;
}
.prose .objectives,
.prose .callout,
.prose .note-box {
  margin: 0 0 1.1em;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid var(--border, #2c2c36);
  background: var(--surface, #18181d);
}
.prose .tag {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  font: 700 10px system-ui;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-right: 4px;
}
.prose .tag.impl { background: rgba(0, 255, 163, 0.15); color: var(--grin, #00ffa3); }
.prose .tag.meta { background: rgba(0, 212, 255, 0.15); color: var(--neon-b, #00d4ff); }
.prose .tag.phil { background: rgba(196, 77, 255, 0.15); color: #d4a0ff; }

.reader-foot {
  text-align: center;
  padding: 12px 16px 20px;
  border-top: 1px solid var(--border, #2c2c36);
}
.reader-foot .copy {
  font: 11px var(--mono, ui-monospace, monospace);
  color: var(--dim, #5c5c6a);
  letter-spacing: 0.04em;
}
.dim { color: var(--dim, #5c5c6a); }
.err {
  color: #ff8aa8;
  padding: 16px;
  border: 1px solid rgba(255, 45, 106, 0.35);
  border-radius: 10px;
  background: rgba(255, 45, 106, 0.08);
}
.btn-ghost.tiny {
  padding: 6px 10px;
  font-size: 11px;
}