/* ─── Bookshelf — base styles ────────────────────────────────────────── */
:root {
  --paper: #FFFFFF;
  --paper-2: #FAF9F6;
  --paper-3: #F4F1EA;
  --ink: #0A0A0A;
  --ink-2: #1A1A1A;
  --ink-mute: rgba(10,10,10,.55);
  --ink-faint: rgba(10,10,10,.35);
  --hair: rgba(10,10,10,.10);
  --hair-strong: rgba(10,10,10,.20);

  /* Beast Creative–style: sans only. Inter Tight is the workhorse;
     "display" gets tighter tracking + heavier weights, body stays neutral. */
  --serif: "Inter Tight", -apple-system, BlinkMacSystemFont, "SF Pro Display", system-ui, sans-serif;
  --sans:  "Inter Tight", -apple-system, BlinkMacSystemFont, "SF Pro Text", system-ui, sans-serif;
  --mono:  "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;

  --maxw: 1280px;
  --pad: clamp(20px, 4vw, 56px);
}

[data-theme="dark"] {
  --paper: #0A0A0A;
  --paper-2: #111111;
  --paper-3: #161513;
  --ink: #F4F1EA;
  --ink-2: #E8E4DA;
  --ink-mute: rgba(244,241,234,.60);
  --ink-faint: rgba(244,241,234,.35);
  --hair: rgba(244,241,234,.12);
  --hair-strong: rgba(244,241,234,.22);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-feature-settings: "ss01", "cv11";
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background .25s ease, color .25s ease;
  overflow-x: hidden;
}

/* Type ramp ───────────────────────────────────────────────────────── */
.h-display {
  font-family: var(--sans);
  font-weight: 500;
  font-size: clamp(40px, 6vw, 80px);
  line-height: .98;
  letter-spacing: -0.04em;
  margin: 0;
}
.h-section {
  font-family: var(--sans);
  font-weight: 500;
  font-size: clamp(24px, 2.8vw, 36px);
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin: 0;
}
.eyebrow {
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-mute);
}
.body { font-size: 16px; line-height: 1.55; }
.body-lg { font-size: 19px; line-height: 1.5; letter-spacing: -0.005em; }
.meta { font-family: var(--mono); font-size: 11px; letter-spacing: 0.04em; color: var(--ink-mute); }

/* Minimal top strip ─────────────────────────────────────────────── */
.topstrip {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  backdrop-filter: blur(20px) saturate(160%);
  border-bottom: .5px solid var(--hair);
}
.topstrip-inner {
  max-width: var(--maxw); margin: 0 auto;
  padding: 14px var(--pad);
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px;
}
.topstrip-brand {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--sans); font-weight: 500; font-size: 15px;
  letter-spacing: -0.02em;
}
.topstrip-brand .dot { width: 6px; height: 6px; background: var(--ink); border-radius: 50%; display: inline-block; }
.topstrip-by { color: var(--ink-mute); font-weight: 400; }
.topstrip-right { display: flex; align-items: center; gap: 16px; }
.topstrip-meta {
  font-family: var(--mono); font-size: 10.5px; letter-spacing: 0.14em;
  color: var(--ink-mute); font-weight: 500;
}
@media (max-width: 540px) { .topstrip-meta { display: none; } }

/* Top nav (legacy, unused) ─────────────────────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  backdrop-filter: blur(20px) saturate(160%);
  border-bottom: .5px solid var(--hair);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 14px var(--pad);
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px;
}
.nav-brand {
  font-family: var(--serif);
  font-size: 19px;
  letter-spacing: -0.02em;
  display: flex; align-items: center; gap: 10px;
}
.nav-brand .dot { width: 6px; height: 6px; background: var(--ink); border-radius: 50%; display: inline-block; }
.nav-links { display: flex; align-items: center; gap: 28px; font-size: 13.5px; }
.nav-links a { color: var(--ink-mute); text-decoration: none; transition: color .15s; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--ink); }
.nav-icon-btn {
  appearance: none; border: 0; background: transparent; color: var(--ink-mute);
  width: 32px; height: 32px; border-radius: 8px; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
}
.nav-icon-btn:hover { background: var(--hair); color: var(--ink); }

/* Main content ───────────────────────────────────────────────────── */
.page { max-width: var(--maxw); margin: 0 auto; padding: 0 var(--pad); }
.section-rule { border-top: .5px solid var(--hair); margin: 0; }

/* Hero ──────────────────────────────────────────────────────────── */
.hero { padding: clamp(56px, 9vw, 128px) 0 clamp(40px, 6vw, 80px); }
.hero-eyebrow-row {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 24px; margin-bottom: clamp(36px, 6vw, 72px);
}
.hero-title { max-width: 14ch; }
.hero-title .ital { font-style: italic; font-weight: 300; color: var(--ink-mute); }
.hero-sub {
  margin-top: clamp(24px, 3vw, 36px);
  max-width: 52ch;
  color: var(--ink-mute);
  font-size: clamp(17px, 1.6vw, 21px);
  line-height: 1.5;
  letter-spacing: -0.005em;
}
.hero-meta {
  margin-top: clamp(40px, 5vw, 64px);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  border-top: .5px solid var(--hair);
  padding-top: 20px;
}
.hero-meta dt { font-family: var(--mono); font-size: 10.5px; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-faint); margin-bottom: 6px; }
.hero-meta dd { margin: 0; font-size: 14px; color: var(--ink); font-variant-numeric: tabular-nums; }

@media (max-width: 720px) {
  .hero-meta { grid-template-columns: repeat(2, 1fr); }
  .hero-eyebrow-row { flex-direction: column; align-items: flex-start; }
}

/* Author note ──────────────────────────────────────────────────── */
.note {
  padding: clamp(48px, 7vw, 96px) 0 clamp(32px, 4vw, 56px);
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: clamp(24px, 4vw, 64px);
}
.note .eyebrow { padding-top: 6px; }
.note p { font-family: var(--sans); font-weight: 400; font-size: clamp(18px, 1.8vw, 22px); line-height: 1.45; letter-spacing: -0.015em; max-width: 52ch; margin: 0; color: var(--ink); }
.note p + p { margin-top: 1em; }
.note p .mute { color: var(--ink-mute); }
.note .sig { margin-top: 24px; font-family: var(--sans); color: var(--ink-mute); font-size: 14px; letter-spacing: -0.005em; }
@media (max-width: 720px) {
  .note { grid-template-columns: 1fr; }
}

/* Filter bar ───────────────────────────────────────────────────── */
.filter-bar {
  position: sticky; top: 56px; z-index: 30;
  background: color-mix(in srgb, var(--paper) 92%, transparent);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  border-top: .5px solid var(--hair);
  border-bottom: .5px solid var(--hair);
  padding: 14px 0;
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.filter-tabs { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; }
.filter-tabs button {
  appearance: none; border: 0; background: transparent;
  font-family: var(--sans); font-size: 13px; font-weight: 500;
  color: var(--ink-mute); padding: 6px 12px; border-radius: 999px;
  cursor: pointer; transition: all .15s;
}
.filter-tabs button[aria-pressed="true"] { background: var(--ink); color: var(--paper); }
.filter-tabs button:hover:not([aria-pressed="true"]) { color: var(--ink); background: var(--hair); }

.filter-right { display: flex; align-items: center; gap: 12px; }
.search-box {
  display: flex; align-items: center; gap: 8px;
  border: .5px solid var(--hair-strong); border-radius: 999px;
  padding: 6px 14px; min-width: 220px;
  background: var(--paper);
}
.search-box input {
  border: 0; outline: 0; background: transparent; color: var(--ink);
  font: inherit; font-size: 13px; width: 100%;
}
.search-box input::placeholder { color: var(--ink-faint); }
.search-box svg { color: var(--ink-faint); flex-shrink: 0; }
.layout-toggle { display: flex; gap: 2px; padding: 2px; border-radius: 8px; background: var(--hair); }
.layout-toggle button {
  appearance: none; border: 0; background: transparent;
  width: 28px; height: 26px; border-radius: 6px;
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--ink-mute); cursor: pointer;
}
.layout-toggle button[aria-pressed="true"] { background: var(--paper); color: var(--ink); box-shadow: 0 1px 2px rgba(0,0,0,.06); }

/* Shelf grid ────────────────────────────────────────────────────── */
.shelf {
  padding: clamp(40px, 6vw, 80px) 0 clamp(60px, 8vw, 120px);
}
.grid-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: clamp(28px, 3.2vw, 56px) clamp(20px, 2.4vw, 40px);
}
@media (max-width: 1080px) { .grid-cards { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 760px) { .grid-cards { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 460px) { .grid-cards { grid-template-columns: 1fr; } }

/* Index list view ─────────────────────────────────────────────── */
.grid-list { display: flex; flex-direction: column; }
.grid-list .row {
  display: grid;
  grid-template-columns: 60px 2fr 1.4fr 80px 80px 24px;
  gap: 24px;
  align-items: center;
  padding: 18px 0;
  border-top: .5px solid var(--hair);
  cursor: pointer;
  transition: background .15s;
}
.grid-list .row:last-child { border-bottom: .5px solid var(--hair); }
.grid-list .row:hover { background: var(--paper-2); }
.grid-list .row .num { font-family: var(--mono); font-size: 11px; color: var(--ink-faint); }
.grid-list .row .ttl { font-family: var(--sans); font-weight: 500; font-size: 19px; line-height: 1.2; letter-spacing: -0.02em; }
.grid-list .row .sub { color: var(--ink-mute); font-size: 13.5px; }
.grid-list .row .yr, .grid-list .row .pg { font-family: var(--mono); font-size: 11.5px; color: var(--ink-mute); }
.grid-list .row .arr { color: var(--ink-faint); }
.grid-list .row:hover .arr { color: var(--ink); transform: translateX(2px); transition: all .15s; }
@media (max-width: 760px) {
  .grid-list .row { grid-template-columns: 32px 1fr 60px; }
  .grid-list .row .sub, .grid-list .row .yr, .grid-list .row .arr { display: none; }
}

/* Newsletter footer ───────────────────────────────────────────── */
.footer {
  border-top: .5px solid var(--hair);
  padding: clamp(48px, 7vw, 96px) 0 clamp(36px, 5vw, 64px);
}
.footer-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: clamp(32px, 5vw, 80px); align-items: end; }
.footer-pitch h3 { font-family: var(--sans); font-weight: 500; font-size: clamp(24px, 2.6vw, 34px); line-height: 1.05; letter-spacing: -0.03em; margin: 0 0 12px; max-width: 18ch; }
.footer-pitch p { color: var(--ink-mute); margin: 0; max-width: 42ch; line-height: 1.55; font-size: 15px; }
.signup {
  display: flex; align-items: stretch; gap: 0;
  border: .5px solid var(--hair-strong); border-radius: 999px;
  padding: 4px 4px 4px 20px; background: var(--paper);
  transition: border-color .15s;
}
.signup:focus-within { border-color: var(--ink); }
.signup input { flex: 1; min-width: 0; border: 0; outline: 0; background: transparent; color: var(--ink); font: inherit; font-size: 14px; }
.signup input::placeholder { color: var(--ink-faint); }
.signup button {
  appearance: none; border: 0; background: var(--ink); color: var(--paper);
  font-family: var(--sans); font-weight: 500; font-size: 13px;
  padding: 0 20px; border-radius: 999px; cursor: pointer;
  transition: opacity .15s;
}
.signup button:hover { opacity: .85; }
.signup-note { font-size: 12px; color: var(--ink-faint); margin-top: 10px; padding-left: 20px; }

.footer-bottom {
  margin-top: clamp(48px, 6vw, 80px);
  padding-top: 24px;
  border-top: .5px solid var(--hair);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 16px;
  font-family: var(--mono); font-size: 11px; color: var(--ink-faint);
  letter-spacing: 0.04em;
}
.footer-bottom .links { display: flex; gap: 24px; }
.footer-bottom a { color: var(--ink-faint); text-decoration: none; }
.footer-bottom a:hover { color: var(--ink); }
@media (max-width: 760px) {
  .footer-grid { grid-template-columns: 1fr; }
}

/* Buttons (shared) ─────────────────────────────────────────────── */
.btn {
  appearance: none; border: 0; cursor: pointer;
  font-family: var(--sans); font-weight: 500; font-size: 14px;
  padding: 12px 22px; border-radius: 999px;
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  transition: all .15s;
  text-decoration: none;
}
.btn-primary { background: var(--ink); color: var(--paper); }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 6px 18px rgba(0,0,0,.12); }
.btn-ghost { background: transparent; color: var(--ink); border: .5px solid var(--hair-strong); }
.btn-ghost:hover { border-color: var(--ink); }
.btn-mini { padding: 7px 12px; font-size: 12px; border-radius: 7px; border: .5px solid var(--hair-strong); background: var(--paper); color: var(--ink); }
.btn-mini:hover { border-color: var(--ink); }

/* Modal / detail overlay ───────────────────────────────────────── */
.detail-overlay {
  position: fixed; inset: 0; z-index: 100;
  background: var(--paper);
  overflow-y: auto;
  animation: fadeIn .25s ease;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes slideUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
@keyframes scaleIn { from { opacity: 0; transform: scale(.96); } to { opacity: 1; transform: scale(1); } }

.detail-close-bar {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  border-bottom: .5px solid var(--hair);
}
.detail-close-bar-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 14px var(--pad);
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
}
.crumb { font-family: var(--mono); font-size: 11.5px; letter-spacing: 0.06em; color: var(--ink-mute); }
.crumb a { color: var(--ink-mute); text-decoration: none; }
.crumb a:hover { color: var(--ink); }
.crumb .sep { color: var(--ink-faint); margin: 0 8px; }

/* Detail page layout ──────────────────────────────────────────── */
.detail-page { max-width: var(--maxw); margin: 0 auto; padding: clamp(40px, 6vw, 80px) var(--pad) clamp(60px, 8vw, 120px); animation: slideUp .35s cubic-bezier(.2,.7,.3,1); }
.detail-hero {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: clamp(40px, 6vw, 96px);
  align-items: start;
}
.detail-cover-wrap { position: sticky; top: 100px; }
.detail-meta-row {
  display: flex; gap: 24px; margin-bottom: 16px;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-mute);
}
.detail-title { font-family: var(--sans); font-size: clamp(36px, 4.8vw, 64px); line-height: 1; letter-spacing: -0.035em; margin: 0; font-weight: 500; }
.detail-sub { font-family: var(--sans); font-weight: 400; font-size: clamp(18px, 1.9vw, 24px); line-height: 1.3; color: var(--ink-mute); margin: 16px 0 0; max-width: 32ch; letter-spacing: -0.015em; }
.detail-desc { margin-top: 32px; font-size: 17px; line-height: 1.6; color: var(--ink); max-width: 52ch; }
.detail-stats {
  margin-top: 32px;
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px;
  border-top: .5px solid var(--hair); border-bottom: .5px solid var(--hair);
  padding: 20px 0;
}
.detail-stats > div { display: flex; flex-direction: column; gap: 4px; }
.detail-stats dt { font-family: var(--mono); font-size: 10.5px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-faint); }
.detail-stats dd { margin: 0; font-family: var(--sans); font-weight: 500; font-size: 19px; letter-spacing: -0.02em; color: var(--ink); }

.detail-actions { margin-top: 32px; display: flex; gap: 12px; flex-wrap: wrap; }
.formats { margin-top: 28px; }
.formats h4 { font-family: var(--mono); font-size: 11px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--ink-mute); margin: 0 0 12px; font-weight: 500; }
.format-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 8px; }
.format-row {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 16px;
  border: .5px solid var(--hair); border-radius: 10px;
  cursor: pointer; transition: all .15s;
  background: var(--paper);
  text-decoration: none; color: inherit;
}
.format-row:hover { border-color: var(--ink); transform: translateY(-1px); }
.format-row .l { display: flex; align-items: center; gap: 12px; }
.format-row .ext { font-family: var(--mono); font-weight: 600; font-size: 11px; letter-spacing: 0.08em; color: var(--ink); }
.format-row .desc { font-size: 12.5px; color: var(--ink-mute); }
.format-row .size { font-family: var(--mono); font-size: 11px; color: var(--ink-faint); }

.toc-block { margin-top: clamp(60px, 8vw, 120px); border-top: .5px solid var(--hair); padding-top: clamp(40px, 5vw, 64px); }
.toc-block h3 { font-family: var(--mono); font-size: 11px; letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-mute); margin: 0 0 32px; font-weight: 500; }
.toc-list { display: grid; grid-template-columns: 1fr 1fr; gap: 24px 64px; }
.toc-list .item { display: flex; gap: 24px; padding: 12px 0; border-bottom: .5px solid var(--hair); font-family: var(--sans); font-weight: 400; font-size: 16px; letter-spacing: -0.015em; }
.toc-list .item .n { font-family: var(--mono); font-size: 11px; color: var(--ink-faint); width: 24px; flex-shrink: 0; padding-top: 6px; }
@media (max-width: 760px) {
  .detail-hero { grid-template-columns: 1fr; }
  .detail-cover-wrap { position: static; max-width: 280px; margin: 0 auto; }
  .detail-stats { grid-template-columns: repeat(2, 1fr); }
  .toc-list { grid-template-columns: 1fr; }
  .format-grid { grid-template-columns: 1fr; }
}

/* Newsletter prompt modal (post-download) ─────────────────────── */
.np-backdrop {
  position: fixed; inset: 0; z-index: 200;
  background: rgba(10,10,10,.45);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
  display: flex; align-items: center; justify-content: center;
  padding: 24px;
  animation: fadeIn .2s ease;
}
.np-card {
  background: var(--paper); color: var(--ink);
  width: 100%; max-width: 420px;
  border-radius: 20px;
  padding: 32px;
  border: .5px solid var(--hair-strong);
  box-shadow: 0 30px 80px rgba(0,0,0,.25);
  animation: scaleIn .25s cubic-bezier(.2,.7,.3,1);
}
.np-card .icon-wrap { width: 44px; height: 44px; border-radius: 12px; background: var(--paper-3); display: flex; align-items: center; justify-content: center; margin-bottom: 16px; color: var(--ink); }
.np-card h3 { font-family: var(--sans); font-weight: 500; font-size: 22px; line-height: 1.15; letter-spacing: -0.03em; margin: 0 0 8px; }
.np-card p { color: var(--ink-mute); font-size: 14px; line-height: 1.55; margin: 0 0 20px; }
.np-card .actions { display: flex; gap: 8px; margin-top: 16px; }
.np-card .actions .btn { flex: 1; }
.np-card input.signup-inline {
  width: 100%; padding: 12px 14px;
  border: .5px solid var(--hair-strong); border-radius: 10px;
  font: inherit; font-size: 14px; color: var(--ink); background: var(--paper);
  outline: none;
}
.np-card input.signup-inline:focus { border-color: var(--ink); }
.np-skip { font-size: 12px; color: var(--ink-faint); background: 0; border: 0; cursor: pointer; padding: 8px; font-family: var(--sans); margin-top: 4px; }
.np-skip:hover { color: var(--ink); }