/* =====================================================================
   TOP TEN BEST BOOKS — SHARED DESIGN SYSTEM
   AI Reference Publishers
   ---------------------------------------------------------------------
   This file is the single source of truth for the site's look.
   Every page links to it:  <link rel="stylesheet" href="styles.css">
   Do not restyle inside individual pages — change it here and all
   pages (B, BC, BD, BF, …) update together and stay identical.
   ===================================================================== */

:root{
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*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
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a{color:inherit;}

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.wrap{width:100%;max-width:1080px;margin:0 auto;padding:0 2rem;}

/* ── Utility bar ───────────────────────────── */
.util{
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/* ── Hero / cover ──────────────────────────── */
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.cover .wrap{padding-top:4.5rem;padding-bottom:4.75rem;}
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.meta-line{margin:2.4rem auto 0;max-width:46rem;font-size:.95rem;color:#cdc4ad;line-height:1.7;}

/* ── Nav ───────────────────────────────────── */
nav.site{
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nav.site .wrap{display:flex;flex-wrap:wrap;align-items:center;gap:.25rem 1.4rem;padding-top:.85rem;padding-bottom:.85rem;}
nav.site .brand{
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nav.site a.link:hover,nav.site a.link:focus-visible{color:var(--buckram);border-bottom-color:var(--brass);}
nav.site a.link[aria-current="page"]{color:var(--buckram);border-bottom-color:var(--brass);}

/* ── Prose sections ────────────────────────── */
main{padding:1rem 0 0;}
section{padding:3.4rem 0;border-bottom:1px solid var(--rule-soft);}
section:last-of-type{border-bottom:none;}
.sec-head{display:flex;align-items:baseline;gap:1rem;margin:0 0 1.6rem;}
.sec-num{font-family:"IBM Plex Mono",monospace;font-size:.78rem;color:var(--brass);letter-spacing:.1em;padding-top:.35rem;flex:none;}
h2,.sec-head h1{font-family:"Fraunces",serif;font-weight:600;font-size:clamp(1.55rem,3.4vw,2.2rem);line-height:1.1;letter-spacing:-.012em;margin:0;color:var(--ink);}
.prose{max-width:48rem;}
.prose p{margin:0 0 1.25rem;}
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.lead{font-size:1.06rem;}

/* ── Classification cards (homepage grid) ──── */
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:1.4rem;margin-top:2rem;}
.card{
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.card .ctitle{font-family:"Fraunces",serif;font-weight:600;font-size:1.28rem;margin:.55rem 0 .35rem;line-height:1.15;}
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.card .cdesc{font-size:.95rem;color:var(--ink-soft);line-height:1.6;margin:0;}
.card .more{margin-top:1.15rem;font-family:"IBM Plex Mono",monospace;font-size:.72rem;letter-spacing:.12em;text-transform:uppercase;color:var(--buckram);}
.card:hover .more{color:var(--brass);}

/* =====================================================================
   CLASSIFICATION-DETAIL COMPONENTS
   For pages like BF that list annotated works by time period.
   ===================================================================== */

/* Period group heading (e.g. "Pre-1900 Historical") */
.period{
  display:flex;align-items:baseline;gap:1rem;
  margin:2.6rem 0 1.6rem;padding-bottom:.7rem;border-bottom:2px solid var(--buckram);
}
.period .pname{font-family:"Fraunces",serif;font-weight:600;font-size:1.5rem;letter-spacing:-.01em;margin:0;}
.period .pmeta{font-family:"IBM Plex Mono",monospace;font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--brass);margin-left:auto;white-space:nowrap;}

/* A single annotated book entry */
.entry{display:flex;gap:1.4rem;padding:1.7rem 0;border-bottom:1px solid var(--rule-soft);}
.entry:last-child{border-bottom:none;}
.entry-num{font-family:"Fraunces",serif;font-weight:700;font-size:1.6rem;color:var(--brass);line-height:1.1;flex:none;width:2.2rem;text-align:right;}
.entry-body{flex:1;min-width:0;}
.entry-cite{font-family:"Fraunces",serif;font-weight:600;font-size:1.18rem;line-height:1.25;margin:0 0 .15rem;}
.entry-cite em{font-style:italic;}
.entry-call{font-family:"IBM Plex Mono",monospace;font-size:.72rem;letter-spacing:.06em;color:var(--brass);margin-bottom:.7rem;}
.entry-citation{font-family:"Spectral",Georgia,serif;font-size:.86rem;color:var(--muted);line-height:1.5;margin:0 0 .65rem;}
.annotation{font-size:.98rem;color:var(--ink-soft);line-height:1.62;margin:0;}
.buy{
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  color:var(--buckram);text-decoration:none;border:1px solid var(--rule);border-radius:2px;
  padding:.4rem .85rem;transition:.18s;
}
.buy:hover,.buy:focus-visible{border-color:var(--brass);color:var(--brass);background:var(--paper-card);}

/* Sources list */
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.sources li{margin:0 0 .6rem;}
.bib-sub{font-family:"IBM Plex Mono",monospace;font-size:.72rem;letter-spacing:.1em;text-transform:uppercase;color:var(--brass);margin:1.8rem 0 .7rem;}
.bib-list{list-style:none;margin:0;padding:0;max-width:48rem;}
.bib-list li{font-size:.9rem;color:var(--ink-soft);line-height:1.5;padding:.35rem 0 .35rem 1.6rem;text-indent:-1.6rem;border-bottom:1px solid var(--rule-soft);}
.bib-list li:last-child{border-bottom:none;}

/* A–Z index lists (Authors, Titles) */
.index-list{list-style:none;margin:0;padding:0;max-width:48rem;}
.index-list li{padding:.5rem 0;border-bottom:1px solid var(--rule-soft);font-size:.95rem;line-height:1.5;color:var(--ink-soft);}
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.index-letter{font-family:"Fraunces",serif;font-weight:700;font-size:1.35rem;color:var(--brass);margin:2.2rem 0 .3rem;border-bottom:2px solid var(--buckram);padding-bottom:.3rem;}
.index-letter:first-of-type{margin-top:.5rem;}

/* Related classifications — cross-references to other LC classes */
.related{list-style:none;margin:1.6rem 0 0;padding:0;max-width:48rem;}
.related li{display:flex;gap:1rem;padding:.85rem 0;border-bottom:1px solid var(--rule-soft);}
.related li:last-child{border-bottom:none;}
.related .rcode{font-family:"IBM Plex Mono",monospace;font-weight:500;font-size:.95rem;color:var(--brass);flex:none;width:2.6rem;padding-top:.05rem;}
.related .rtext{font-size:.97rem;color:var(--ink-soft);line-height:1.55;margin:0;}
.related .rtext strong{color:var(--buckram-deep);font-weight:600;}

/* Forthcoming / inactive classification card (non-link) */
.card.soon{opacity:.7;cursor:default;}
.card.soon:hover{transform:none;box-shadow:none;border-top-color:var(--rule);}
.card .tag{display:inline-block;margin-top:1.15rem;font-family:"IBM Plex Mono",monospace;font-size:.68rem;letter-spacing:.12em;text-transform:uppercase;color:var(--muted);border:1px dashed var(--rule);border-radius:2px;padding:.25rem .6rem;}

/* ── Footer ────────────────────────────────── */
footer{background:var(--buckram-deep);color:#bdb39c;font-family:"IBM Plex Mono",monospace;font-size:.78rem;letter-spacing:.04em;}
footer .wrap{padding-top:2.4rem;padding-bottom:2.4rem;text-align:center;}
footer .ftitle{color:var(--brass-bright);}

/* ── Responsive ────────────────────────────── */
@media (max-width:820px){
  .cards{grid-template-columns:1fr;}
  .cover-frame{padding:2.4rem 1.4rem;}
  nav.site .brand{width:100%;margin-bottom:.4rem;}
}
@media (max-width:520px){
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  body{font-size:17px;}
  .sec-head{flex-direction:column;gap:.3rem;}
  .entry{gap:.9rem;}
  .entry-num{width:1.6rem;font-size:1.3rem;}
  .period{flex-wrap:wrap;}
  .period .pmeta{margin-left:0;}
}
@media (prefers-reduced-motion:reduce){
  *{scroll-behavior:auto;transition:none!important;}
  .card:hover{transform:none;}
}